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Background: Isotonic exercise is the most common mode of strength training. Isotonic strength is often measured in the movement that was exercised, but isometric and isokinetic movements are also commonly used to quantify changes in muscular strength. Previous research suggests that increasing strength in one movement may not lead to an increase in strength in a different movement. Quantifying the increase in strength in a movement not trained may be important for understanding strength training adaptations and making recommendations for resistance exercise and rehabilitation programs. Objective: To quantify changes in non-specific strength relative to a control. Design: A systematic review and random effects meta-analysis was conducted investigating the effects of isotonic strength training on isotonic and isokinetic/isometric strength. Search and Inclusion: This systematic review was conducted in Google scholar, PubMed, Academic Search Premier, and MENDELEY. To be included in this review paper the article needed to meet the following criteria: (1) report sufficient data for our variables of interest (i.e., changes in isotonic strength and changes in isokinetic or isometric strength); (2) include a time-matched non-exercise control; (3) be written in English; (4) include healthy human participants over the age of 18 years; (5) the participants had to train and test isotonically; (6) the participants had to be tested isokinetically or isometrically on a device different from that they trained on; (7) the non-specific strength task had to test a muscle involved in the training (i.e., could not have trained chest press and test handgrip strength); and (8) the control group and the experimental group had to perform the same number of strength tests. Results: We completed two separate searches. In the original search a total of 880 papers were screened and nine papers met the inclusion criteria. In the secondary search a total of 2594 papers were screened and three additional papers were added (total of 12 studies). The overall effect of resistance training on changes in strength within a movement that was not directly trained was 0.8 (Cohen's d) with a standard error of 0.286. This overall effect was significant (t = 2.821, p = 0.01) and the 95% confidence interval (CI) is 0.22–1.4. The overall effect of resistance training on strength changes within a movement that was directly trained was 1.84 (Cohen's d) with a standard error of 0.296. This overall effect was significant (t = 6.221, p < 0.001) and the 95% CI is 1.23–2.4. Conclusion: The results of our meta-analysis suggest that strength increases in both the specific and non-specific strength tests. However, the smaller effect size associated with non-specific strength suggests that it will be difficult for a single study to meaningfully investigate the transfer of strength training adaptions. [ABSTRACT FROM AUTHOR]

Background: While the burgeoning researcher and practitioner interest in physical literacy has stimulated new assessment approaches, the optimal tool for assessment among school-aged children remains unclear. Objective: The purpose of this review was to: (i) identify assessment instruments designed to measure physical literacy in school-aged children; (ii) map instruments to a holistic construct of physical literacy (as specified by the Australian Physical Literacy Framework); (iii) document the validity and reliability for these instruments; and (iv) assess the feasibility of these instruments for use in school environments. Design: This systematic review (registered with PROSPERO on 21 August, 2022) was conducted in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement. Data Sources: Reviews of physical literacy assessments in the past 5 years (2017 +) were initially used to identify relevant assessments. Following that, a search (20 July, 2022) in six databases (CINAHL, ERIC, GlobalHealth, MEDLINE, PsycINFO, SPORTDiscus) was conducted for assessments that were missed/or published since publication of the reviews. Each step of screening involved evaluation from two authors, with any issues resolved through discussion with a third author. Nine instruments were identified from eight reviews. The database search identified 375 potential papers of which 67 full text papers were screened, resulting in 39 papers relevant to a physical literacy assessment. Inclusion and Exclusion Criteria: Instruments were classified against the Australian Physical Literacy Framework and needed to have assessed at least three of the Australian Physical Literacy Framework domains (i.e., psychological, social, cognitive, and/or physical). Analyses: Instruments were assessed for five aspects of validity (test content, response processes, internal structure, relations with other variables, and the consequences of testing). Feasibility in schools was documented according to time, space, equipment, training, and qualifications. Results: Assessments with more validity/reliability evidence, according to age, were as follows: for children, the Physical Literacy in Children Questionnaire (PL-C Quest) and Passport for Life (PFL). For older children and adolescents, the Canadian Assessment for Physical Literacy (CAPL version 2). For adolescents, the Adolescent Physical Literacy Questionnaire (APLQ) and Portuguese Physical Literacy Assessment Questionnaire (PPLA-Q). Survey-based instruments were appraised to be the most feasible to administer in schools. Conclusions: This review identified optimal physical literacy assessments for children and adolescents based on current validity and reliability data. Instrument validity for specific populations was a clear gap, particularly for children with disability. While survey-based instruments were deemed the most feasible for use in schools, a comprehensive assessment may arguably require objective measures for elements in the physical domain. If a physical literacy assessment in schools is to be performed by teachers, this may require linking physical literacy to the curriculum and developing teachers' skills to develop and assess children's physical literacy. [ABSTRACT FROM AUTHOR]

The objective of this review was to examine the ratio of female and male participants utilised in data informing consensus statements and position stands in the field of resistance training (RT). In order to achieve this objective, we conducted an 'audit' style review. We accessed three databases: SPORTDiscus, MEDLINE and Google Scholar utilising the following search terms: resistance or strength training AND consensus statements or position statements/stands. Eligibility criteria included consensus statements and position stands for RT in youth, adults and older adults. In this paper we have used the term 'female' to describe biological sex. Gender is a social construct and often describes roles and behaviours that society assigns to men or women. In this paper we have used the term 'women' to describe gender. Reference lists from each guideline were screened with the number of male and female participants extracted from each study. We also extracted data on the gender of the authors of the statements. We located 11 guidelines encompassing a total of 104,251,363 participants. Youth guidelines were comprised of 69% male participants. There were 287 studies that included both sexes, 205 male-only and 92 female-only studies. Adult guidelines were comprised of 70% male participants. There were 104 studies that included both sexes, 240 male-only and 44 female-only studies. Older adult guidelines were comprised of 54% female participants. There were 395 studies that included both sexes, 112 male-only and 83 female-only studies. Women authors comprised 13% of all authors of position stands and consensus statements. These results demonstrate an under-representation of females and women as both participants and as authors. It is imperative to ensure that data informing governing body guidelines and consensus statements are representative of the population they aim to inform. If this is not possible, guidelines should clearly state when their data and recommendations are based primarily upon one sex. [ABSTRACT FROM AUTHOR]

Background: The concept of physical literacy has stimulated increased research attention in recent years-being deployed in physical education, sport participation, and the promotion of physical activity. Independent research groups currently operationalize the construct differently. Objective: The purpose of this systematic review was to conduct a systematic review of the physical literacy construct, as reflected in contemporary research literature. Methods: Five databases were searched using the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines for systematic reviews. Inclusion criteria were English language, peer reviewed, published by March 2016, and seeking to conceptualize physical literacy. Articles that met these criteria were analyzed in relation to three core areas: properties/attributes, philosophical foundations and theoretical associations with other constructs. A total of 50 published articles met the inclusion criteria and were analyzed qualitatively using inductive thematic analysis. Results: The thematic analysis addressed the three core areas. Under definitions, core attributes that define physical literacy were identified, as well as areas of conflict between different approaches currently being adopted. One relatively clear philosophical approach was prominent in approximately half of the papers, based on a monist/holistic ontology and phenomenological epistemology. Finally, the analysis identified a number of theoretical associations, including health, physical activity and academic performance. Conclusions: Current literature contains different representations of the physical literacy construct. The costs and benefits of adopting an exclusive approach versus pluralism are considered. Recommendations for both researchers and practitioners focus on identifying and clearly articulating the definitions, philosophical assumptions and expected outcomes prior to evaluating the effectiveness of this emerging concept. [ABSTRACT FROM AUTHOR]

Background: Elevated glucose and insulin levels are major risk factors in the development of cardiometabolic disease. Aerobic exercise is widely recommended to improve glycaemic control, yet its acute effect on glycaemia and glucoregulatory hormones has not been systematically reviewed and analysed in healthy adults. Objective: To determine the effect of a single bout of continuous aerobic exercise on circulating glucose, insulin, and glucagon concentrations in healthy adults. Methods: CENTRAL, CINAHL, Embase, Global Health, HMIC, Medline, PubMed, PsycINFO, ScienceDirect, Scopus and Web of Science databases were searched from inception to May 2020. Papers were included if they reported a randomised, crossover study measuring glucose and/or insulin and/or glucagon concentrations before and immediately after a single bout of continuous aerobic exercise (≥ 30 min) compared to a time-matched, resting control arm in healthy adults. The risk of bias and quality of evidence were assessed using the Cochrane Risk of Bias Tool and GRADE approach, respectively. Random-effects meta-analyses were performed for glucose, insulin, and glucagon. Sub-group meta-analyses and meta-regression were performed for categorical (metabolic state [postprandial or fasted], exercise mode [cycle ergometer or treadmill]) and continuous (age, body mass index, % males, maximal aerobic capacity, exercise duration, exercise intensity) covariates, respectively. Results: 42 papers (51 studies) were considered eligible: glucose (45 studies, 391 participants), insulin (38 studies, 377 participants) and glucagon (5 studies, 47 participants). Acute aerobic exercise had no significant effect on glucose concentrations (mean difference: − 0.05 mmol/L; 95% CI, − 0.22 to 0.13 mmol/L; P = 0.589; I2: 91.08%, large heterogeneity; moderate-quality evidence). Acute aerobic exercise significantly decreased insulin concentrations (mean difference: − 18.07 pmol/L; 95% CI, − 30.47 to − 5.66 pmol/L; P = 0.004; I2: 95.39%, large heterogeneity; moderate-quality evidence) and significantly increased glucagon concentrations (mean difference: 24.60 ng/L; 95% CI, 16.25 to 32.95 ng/L; P < 0.001; I2: 79.36%, large heterogeneity; moderate-quality evidence). Sub-group meta-analyses identified that metabolic state modified glucose and insulin responses, in which aerobic exercise significantly decreased glucose (mean difference: − 0.27 mmol/L; 95% CI, − 0.55 to − 0.00 mmol/L; P = 0.049; I2: 89.72%, large heterogeneity) and insulin (mean difference: − 42.63 pmol/L; 95% CI, − 66.18 to − 19.09 pmol/L; P < 0.001; I2: 81.29%, large heterogeneity) concentrations in the postprandial but not fasted state. Meta-regression revealed that the glucose concentrations were also moderated by exercise duration and maximal aerobic capacity. Conclusions: Acute aerobic exercise performed in the postprandial state decreases glucose and insulin concentrations in healthy adults. Acute aerobic exercise also increases glucagon concentrations irrespective of metabolic state. Therefore, aerobic exercise undertaken in the postprandial state is an effective strategy to improve acute glycaemic control in healthy adults, supporting the role of aerobic exercise in reducing cardiometabolic disease incidence. PROSPERO registration number: CRD42020191345. [ABSTRACT FROM AUTHOR]

Background: Individuals with anterior cruciate ligament (ACL) injury often exhibit visual cognitive deficits during tasks that require neuromuscular control. In this paper, we present evidence of increased visual reliance after ACL injury during a range of clinically applicable cognitive–motor tasks. This information is essential to strengthen the scientific rationale for therapeutic interventions that target maladaptive neuroplasticity and may translate to improved return-to-sport (RTS) outcomes following ACL injury. Objectives: The objectives of this study are (1) to determine if visual reliance is present during common rehabilitation-based assessments after ACL deficiency (ACL-D) or ACL reconstruction (ACL-R), (2) to describe how visual reliance is assessed during such tasks, and (3) to provide information to help clinicians and patients understand the clinical relevance of cognitive load in the assessment and intervention of visual reliance. Design: Scoping review. Literature search: We searched MEDLINE, EMBASE, CINAHL, SCOPUS, and PEDro databases. Study selection criteria: Only primary studies published in English were included without time limitations. Data synthesis: Qualitative analysis of the included studies was performed. Results: We synthesized the results of 23 studies. A total of 7 studies (31%) included patients with ACL-D, 15 studies (65%) included patients with ACL-R, and 1 study (4%) included patients with ACL-D and ACL-R. Evaluation of tasks, task evaluation setting, visual conditions, outcome measures, and presence of increased visual reliance were identified. Most studies investigating patients with ACL-D, contrary to those with ACL-R, exhibited worse postural stability during eyes-closed conditions than uninjured controls. Complete visual obstruction (i.e., eyes closed or blindfolded) was the most frequently reported method to disrupt vision (52%). The addition of a visual–cognitive challenge resulted in significantly worse postural stability in patients with ACL-R compared with controls. Conclusions: Visual reliance was most commonly assessed during single leg stance with complete visual obstruction. The majority of studies on patients with ACL-D indicate that they exhibit poorer postural stability in eyes-closed conditions when compared with uninjured controls, which suggests increased visual reliance. There is less evidence of visual reliance in patients who have undergone ACL-R compared with those with ACL-D. Adding a visual–cognitive load was found to be more effective in inducing postural stability deficits in individuals who have undergone ACL-R. Level of evidence: IV. The protocol was a priori registered on Open Science Framework (https://osf.io/p4j95/). [ABSTRACT FROM AUTHOR]

Background: Among ultra-endurance runners (UER), the mental, behavioral, and physical demands of training/competition can result in maladaptive outcomes. Mental health issues are common in athletes and can impact psychology, physical health, and performance. Objective: To synthesize information regarding the incidence/prevalence and factors associated with mental health issues among UER. Methods: Systematic searches were performed in PubMed, SPORTDiscus, Scopus, Cochrane databases, CINAHL, Web of Science, and Medline Ovid using key terms related to UER (e.g., trail running, road running) and psychological issues (e.g., exercise addiction, depression). Inclusion criteria included original articles published in peer-reviewed journals in English, using qualitative or quantitative approaches. We considered papers reporting incidence/prevalence and associated factors with mental health outcomes in UER of both sexes, all ages, and levels of competition (e.g., elite, nonprofessional runners). The Joanna Briggs Institute Analytical Cross-Sectional Studies critical appraisal tool was used for quality assessment. Results: A total of 282 studies were identified, and 11 studies were included in the final selection. A total of 3670 UER were included in the studies. The prevalence of mental health issues among UER ranged between 32.0% and 62.5% for eating disorders, from 11.5% to 18.2% for exercise addiction, 18.6% for depressive symptoms, and 24.5% for sleep disturbance. Exercise addiction was not related to weekly volume, but a strong relationship with exercise in an unstructured space, age, and body mass index was shown. Conclusion: Mental health issues among UER are common, especially eating disorders, exercise addiction, sleep disturbances, and depressive symptoms. Further high-quality studies are needed to examine underlying factors and find preventative strategies to protect UER. Registration: The protocol of this systematic review was registered at the PROSPERO—CRD42022338743. [ABSTRACT FROM AUTHOR]

Background: The concept of physical literacy has received increased research and international attention recently. Where intervention programs and empirical research are gaining momentum, their operationalizations differ significantly.Objective: The objective of this study was to inform practice in the measure/assessment of physical literacy via a systematic review of research that has assessed physical literacy (up to 14 June, 2017).Methods: Five databases were searched using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Protocols guidelines, with 32 published articles meeting the inclusion criteria. English-language, peer-reviewed published papers containing empirical studies of physical literacy were analyzed using inductive thematic analysis.Results: Qualitative methods included: (1) interviews; (2) open-ended questionnaires; (3) reflective diaries; (4) focus groups; (5) participant observations; and (6) visual methods. Quantitative methods included: (1) monitoring devices (e.g., accelerometers); (2) observations (e.g., of physical activity or motor proficiency); (3) psychometrics (e.g., enjoyment, self-perceptions); (4) performance measures (e.g., exergaming, objective times/distances); (5) anthropometric measurements; and (6) one compound measure. Of the measures that made an explicit distinction: 22 (61%) examined the physical domain, eight (22%) the affective domain; five (14%) the cognitive domain; and one (3%) combined three domains (physical, affective, and cognitive) of physical literacy. Researchers tended to declare their philosophical standpoint significantly more in qualitative research compared with quantitative research.Conclusions: Current research adopts diverse often incompatible methodologies in measuring/assessing physical literacy. Our analysis revealed that by adopting simplistic and linear methods, physical literacy cannot be measured/assessed in a traditional/conventional sense. Therefore, we recommend that researchers are more creative in developing integrated philosophically aligned approaches to measuring/assessing physical literacy. Future research should consider the most recent developments in the field of physical literacy for policy formation. [ABSTRACT FROM AUTHOR]

Background: Several studies have utilised isometric, eccentric and downhill walking pre-conditioning as a strategy for alleviating the signs and symptoms of exercise-induced muscle damage (EIMD) following a bout of damaging physical activity. Objectives: This systematic review and meta-analysis examined the effects of pre-conditioning strategies on indices of muscle damage and physical performance measures following a second bout of strenuous physical activity. Data Sources: PubMed, CINAHL and Scopus. Eligibility Criteria: Studies meeting the PICO (population, intervention/exposure, comparison, and outcome) criteria were included in this review: (1) general population or "untrained" participants with no contraindications affecting physical performance; (2) studies with a parallel design to examine the prevention and severity of muscle-damaging contractions; (3) outcome measures were compared using baseline and post-intervention measures; and (4) outcome measures included any markers of indirect muscle damage and muscular contractility measures. Participants: Individuals with no resistance training experiences in the previous 6 or more months. Interventions: A single bout of pre-conditioning exercises consisting of eccentric or isometric contractions performed a minimum of 24 h prior to a bout of damaging physical activity were compared to control interventions that did not perform pre-conditioning prior to damaging physical activity. Study Appraisal: Kmet appraisal system. Synthesis Methods: Quantitative analysis was conducted using forest plots to examine standardised mean differences (SMD, i.e. effect size), test statistics for statistical significance (i.e. Z-values) and between-study heterogeneity by inspecting I2. Results: Following abstract and full-text screening, 23 articles were included in this paper. Based on the meta-analysis, the pre-conditioning group exhibited lower levels of creatine kinase at 24 h (SMD = − 1.64; Z = 8.39; p = 0.00001), 48 h (SMD = − 2.65; Z = 7.78; p = 0.00001), 72 h (SMD = − 2.39; Z = 5.71; p = 0.00001) and 96 h post-exercise (SMD = − 3.52; Z = 7.39; p = 0.00001) than the control group. Delayed-onset muscle soreness was also lower for the pre-conditioning group at 24 h (SMD = − 1.89; Z = 6.17; p = 0.00001), 48 h (SMD = − 2.50; Z = 7.99; p = 0.00001), 72 h (SMD = − 2.73; Z = 7.86; p = 0.00001) and 96 h post-exercise (SMD = − 3.30; Z = 8.47; p = 0.00001). Maximal voluntary contraction force was maintained and returned to normal sooner in the pre-conditioning group than in the control group, 24 h (SMD = 1.46; Z = 5.49; p = 0.00001), 48 h (SMD = 1.59; Z = 6.04; p = 0.00001), 72 h (SMD = 2.02; Z = 6.09; p = 0.00001) and 96 h post-exercise (SMD = 2.16; Z = 5.69; p = 0.00001). Range of motion was better maintained by the pre-conditioning group compared with the control group at 24 h (SMD = 1.48; Z = 4.30; p = 0.00001), 48 h (SMD = 2.20; Z = 5.64; p = 0.00001), 72 h (SMD = 2.66; Z = 5.42; p = 0.00001) and 96 h post-exercise (SMD = 2.5; Z = 5.46; p = 0.00001). Based on qualitative analyses, pre-conditioning activities were more effective when performed at 2–4 days before the muscle-damaging protocol compared with immediately prior to the muscle-damaging protocol, or 1–3 weeks prior to the muscle-damaging protocol. Furthermore, pre-conditioning activities performed using eccentric contractions over isometric contractions, with higher volumes, greater intensity and more lengthened muscle contractions provided greater protection from EIMD. Limitations: Several outcome measures showed high inter-study heterogeneity. The inability to account for differences in durations between pre-conditioning and the second bout of damaging physical activity was also limiting. Conclusions: Pre-conditioning significantly reduced the severity of creatine kinase release, delayed-onset muscle soreness, loss of maximal voluntary contraction force and the range of motion decrease. Pre-conditioning may prevent severe EIMD and accelerate recovery of muscle force generation capacity. [ABSTRACT FROM AUTHOR]

Background and Objective: While some authors report that dancers have reduced bone mineral density (BMD) and increased risk of osteoporosis, others have stressed the positive effects of dance training on developing healthy BMD. Given the existing controversy, the aim of this systematic review was to examine the best evidence-based information available in relation to female dancers. Methods: Four databases (Web of Science, PubMed, EBSCO, Scopus) and two dance science journals ( Journal of Dance Medicine and Science and Medical Problems of Performing Artists) were searched for relevant material using the keywords 'dance', 'ballet', 'BMD', 'bone density', 'osteoporosis' and 'female athlete triad syndrome'. A total of 257 abstracts were screened using selected inclusion (studies involving bone measurements in dancers) and exclusion (editorials, opinion papers, chapters in books, narrative reviews and non-English language papers) criteria according to PRISMA guidelines. Following the above screening, a total of 108 abstracts were identified as potentially relevant. After the exclusion of conference proceedings, review papers, studies focusing only in male dancers and studies in which dancers' information were combined with other athletes, the eligible papers were subsequently assessed using the GRADE system and grouped according to: (1) prevalence of low BMD and associated factors, (2) incidence of low BMD and risk factors, (3) prevention/treatment of low BMD in dancers, and (4) other studies. Results: Of the 257 abstracts that were initially screened, only 35 studies were finally considered. Only one of these 35 was of high quality, while the remaining 34 were of relatively low quality. Seven studies reported prevalence of low BMD and associated factors, 10 reported associated factors with no prevalence data, while one reported prevalence with no associated factors data. One study cited risk factors, while another one elaborated on the treatment of low BMD in dancers. The remaining 15 studies were classified as 'other studies'. Conclusions: It remains unclear whether low BMD is prevalent in female dancers. The present review highlights the need for high-quality BMD research in this area. [ABSTRACT FROM AUTHOR]

Background: Understanding the determinants of children's health behaviours is important to develop successful behaviour-change interventions. Objective: We aimed to synthesise the evidence around determinants ('preceding predictors') of change in physical activity (PA) in young children (0-6 years of age). Methods: As part of a suite of reviews, prospective quantitative studies investigating change in physical activity in children aged 0-6 years were identified from eight databases (to October 2015): MEDLINE, Embase, CINAHL, PsycINFO, Web of Knowledge, British Nursing Index, Applied Social Sciences Index and Abstracts, and Sociological Abstracts. Determinants and direction of association were extracted, described and synthesised according to the socio-ecological model (individual, interpersonal, organisational, community, policy). Results: Forty-four determinants, predominantly in the interpersonal and organisational domains, were reported across 44 papers (six prospective cohort, 38 interventional); 14 determinants were assessed in four or more papers. Parental monitoring showed a consistent positive association with change in PA; provider training was positively associated with change in children's moderate-to-vigorous PA only. Five (sex, parental goal setting, social support, motor skill training and increased time for PA) showed no clear association. A further seven (child knowledge, parental knowledge, parental motivation, parenting skills, parental self-efficacy, curriculum materials and portable equipment) were consistently not associated with change in children's PA. Maternal role-modelling was positively associated with change in PA in all three studies in which it was examined. Conclusions: A range of studied determinants of change in young children's PA were identified, but only parental monitoring was found to be consistently positively associated. More evidence dealing with community and policy domains from low-/middle-income countries and about lesser-explored modifiable family- and childcare-related determinants is required. International Prospective Register for Systematic Reviews (PROSPERO) Registration Number: CRD42012002881. [ABSTRACT FROM AUTHOR]

Background: The aging process is associated with a progressive decline of neuromuscular function, increased risk of falls and fractures, impaired functional performance, and loss of independence. Plyometric training may mitigate or even reverse such age-related deterioration; however, little research on the effects of plyometric exercises has been performed in older adults.Objective: The objective of this systematic review was to evaluate the safety and efficacy of plyometric training in older adults.Methods: Papers reporting on randomized trials of plyometric training in older adults (≥ 60 years) and published up to December 2017 were sought in the PubMed, SPORTDiscus, Scopus, and EMBASE databases, and their methodological quality was assessed using the Physiotherapy Evidence Database (PEDro) scale. A narrative synthesis of the findings is presented in this systematic review.Results: Of the 2236 identified papers, 18 were included in the review, reporting on 12 different studies with a mean PEDro score of 6.0 (range 4-7). Altogether, 289 subjects (176 females and 113 males) were included in 15 intervention groups with plyometric components (n = 8-36 per group); their mean age ranged from 58.4 to 79.4 years. The plyometric training lasted from 4 weeks to 12 months. Muscular strength, bone health, body composition, postural stability, and jump and physical performance were the most often reported outcomes. No study reported increased occurrence of injuries or other adverse events related to plyometric exercises.Conclusion: Plyometric training is a feasible and safe training option with potential for improving various performance, functional, and health-related outcomes in older persons. [ABSTRACT FROM AUTHOR]

Background: Mental fatigue (MF) is a psychobiological state that impairs endurance performance in healthy athletes. Recently, multiple studies indicated that MF could also impair sport-specific psychomotor performance (SSPP). Nevertheless, a systematic overview detailing the effects of MF on SSPP is currently lacking. Objective: The objective of this study is to collate relevant literature and examine the effect of MF on SSPP. A secondary aim was to create an overview of the potential subjective and physiological factors underlying this MF effect. Methods: PubMed (MEDLINE), Web of Science, PsycINFO and SPORTDiscus were searched (5th of November 2020). Studies were eligible when study outcomes encompassed any form of SSPP skill in a sport-specific context, the intervention was targeted to induce MF, and the population included healthy individuals. The presence of a manipulation check, to indicate the successful induction of MF, was obligatory for inclusion. Secondary outcomes were all outcomes (either physiological or psychological) that could explain the underlying mechanisms of the effect of MF on SSPP. Results: In total, 21 papers were included. MF was successfully induced in all but two studies, which were excluded from further analysis. MF negatively impacts a myriad of SSPP outcomes, including decision-making, reaction time and accuracy outcomes. No changes in physiological outcomes, that could underlie the effect of MF, were reported. Subjectively, only ratings of perceived of exertion increased due to MF in some studies. Conclusions: Overall, the selected papers indicated that MF negatively affects SSPP. Research that assesses brain function, while evaluating the effect of MF on SSPP is essential to create further insight. [ABSTRACT FROM AUTHOR]

Background: Male youth soccer players competing at a high level will typically engage in large volumes of soccer training from a young age. However, it is not known whether the high levels of habitual training that these high-performing players are exposed to limit their ability to respond to strength, plyometric or combined training interventions. Objective: The primary aim of our systematic review and meta-analysis was to compare the specific effects of strength, plyometric and combined training with active controls (standard soccer training) on the strength, power and speed characteristics of high-level, highly trained young male soccer players. Methods: We performed a literature search across PubMed, Scopus, CINAHL, Web of Science and SPORTDiscus to identify controlled studies that implemented strength, plyometric or combined training in high-level male youth soccer players. Participants were defined as high level or highly trained based on established guidelines related to either competition level or age-related weekly hours spent in soccer training. Studies needed to report at least one outcome of lower body strength, squat jump, countermovement jump, horizontal power, acceleration (0–10 m), speed (15–40 m) or change of direction speed. A meta-analysis was then performed using a random-effects model to determine the magnitude (Hedge's g) of training responses and whether effects differed across modes of training. Results: From an initial return of 5464 papers, n = 34 studies met the inclusion criteria and provided a total sample of n = 1396 high-level male youth soccer players. Strength, plyometric and combined training resulted in improvements in strength, squat and countermovement jump, horizontal power, acceleration, change of direction speed (all p < 0.05; g = 0.73–1.08, moderate) and speed (p < 0.05; g = 0.40–0.59, small). Lower body strength was the only outcome where training mode had a significant effect (p < 0.05), with plyometric training producing small effects (g = 0.27, p < 0.05) compared with moderate effects for strength (g = 1.07, p < 0.05) and combined (g = 0.75, p < 0.05) training. Prediction intervals for overall effects (all training modes combined) showed that the greatest confidence that future training will lead to positive effects was in the squat and countermovement jump, horizontal power and acceleration (prediction intervals = 0.03–1.81). Conclusions: High-level, highly trained male youth soccer players can experience positive gains in indices of strength, power and speed from strength, plyometric and combined training, and the magnitude of gains are mostly similar across modes of training. Based on prediction intervals, there is a good level of certainty that future strength, plyometric and combined training in this population would lead to positive improvements in vertical and horizontal power and sprint acceleration. [ABSTRACT FROM AUTHOR]

Background: One of the proposed mechanisms underlying the benefits of sports compression garments may be alterations in peripheral blood flow. Objective: We aimed to determine if sports compression garments alter measures of peripheral blood flow at rest, as well as during, immediately after and in recovery from a physiological challenge (i.e. exercise or an orthostatic challenge). Methods: We conducted a systematic literature search of databases including Scopus, SPORTDiscus and PubMed/MEDLINE. The criteria for inclusion of studies were: (1) original papers in English and a peer-reviewed journal; (2) assessed effect of compression garments on a measure of peripheral blood flow at rest and/or before, during or after a physiological challenge; (3) participants were healthy and without cardiovascular or metabolic disorders; and (4) a study population including athletes and physically active or healthy participants. The PEDro scale was used to assess the methodological quality of the included studies. A random-effects meta-analysis model was used. Changes in blood flow were quantified by standardised mean difference (SMD) [± 95% confidence interval (CI)]. Results: Of the 899 articles identified, 22 studies were included for the meta-analysis. The results indicated sports compression garments improve overall peripheral blood flow (SMD = 0.32, 95% CI 0.13, 0.51, p = 0.001), venous blood flow (SMD = 0.37, 95% CI 0.14, 0.60, p = 0.002) and arterial blood flow (SMD = 0.30, 95% CI 0.01, 0.59, p = 0.04). At rest, sports compression garments did not improve peripheral blood flow (SMD = 0.18, 95% CI − 0.02, 0.39, p = 0.08). However, subgroup analyses revealed sports compression garments enhance venous (SMD = 0.31 95% CI 0.02, 0.60, p = 0.03), but not arterial (SMD = 0.12, 95% CI − 0.16, 0.40, p = 0.16), blood flow. During a physiological challenge, peripheral blood flow was improved (SMD = 0.44, 95% CI 0.19, 0.69, p = 0.0007), with subgroup analyses revealing sports compression garments enhance venous (SMD = 0.48, 95% CI 0.11, 0.85, p = 0.01) and arterial blood flow (SMD = 0.44, 95% CI 0.03, 0.86, p = 0.04). At immediately after a physiological challenge, there were no changes in peripheral blood flow (SMD = − 0.04, 95% CI − 0.43, 0.34, p = 0.82) or subgroup analyses of venous (SMD = − 0.41, 95% CI − 1.32, 0.47, p = 0.35) and arterial (SMD = 0.12, 95% CI − 0.26, 0.51, p = 0.53) blood flow. In recovery, sports compression garments did not improve peripheral blood flow (SMD = 0.25, 95% CI − 0.45, 0.95, p = 0.49). The subgroup analyses showed enhanced venous (SMD = 0.67, 95% CI 0.17, 1.17, p = 0.009), but not arterial blood flow (SMD = 0.02, 95% CI − 1.06, 1.09, p = 0.98). Conclusions: Use of sports compression garments enhances venous blood flow at rest, during and in recovery from, but not immediately after, a physiological challenge. Compression-induced changes in arterial blood flow were only evident during a physiological challenge. [ABSTRACT FROM AUTHOR]

Background: The risk of sustaining a graft rupture after anterior cruciate ligament reconstruction (ACLR) is high. Contributing risk factors are, however, still not clearly identified. Objective: The aim of this systematic review was to identify and quantify risk factors for graft rupture after ACLR. Methods: A systematic review with meta-analysis (PROSPERO CRD42020140129) based on PRISMA guidelines was performed. MEDLINE, CINAHL and EMBASE were searched from inception to September 2021. Prospective and retrospective studies addressing risk factors for graft rupture after ACLR in males/females of all ages were considered. Meta-analyses using a random effect model (effect measure: odds ratio [OR] with 95% confidence interval [CI]) were performed. The GRADE tool was used to assess evidence quality. Results: Following full-text screening of 310 relevant papers, 117 were eventually included, incorporating up to 133,000 individuals in each meta-analysis. Higher Tegner activity level (≥ 7 vs < 7) at primary injury (OR 3.91, 95% CI 1.69–9.04), increased tibial slope (degrees) (OR 2.21, 95% CI 1.26–3.86), lower psychological readiness to return to sport (RTS) (OR 2.18, 95% CI 1.32–3.61), early surgery (< 12 vs ≥ 12 months) (OR 1.87, 95% CI 1.58–2.22), RTS (pre-injury level) (OR 1.87, 95% CI 1.21–2.91) and family history of ACL injury (OR 1.76, 95% CI 1.34–2.31) were all associated with increased odds of graft rupture. Higher age (OR 0.47, 95% CI 0.39–0.59), female sex (OR 0.88, 95% CI 0.79–0.98), fewer self-reported knee symptoms pre-reconstruction (OR 0.81, 95% CI 0.69–0.95) and concomitant cartilage injuries (OR 0.70, 95% CI 0.62–0.79) instead decreased the odds. Meta-analysis revealed no association between body mass index, smoking, joint laxity, RTS time, knee kinematics, muscle strength or hop performance and graft rupture. Conclusion: Conspicuous risk factors for graft rupture were mainly sports and hereditary related. Few studies investigated function-related modifiable factors or included sports exposure data. [ABSTRACT FROM AUTHOR]

Background: Recreational football is an intense, versatile form of exercise with multiple high- and odd-impact actions. Recreational football is therefore hypothesized to be suitable for bone modeling and bone health. Objective: The aim of the present systematic review and meta-analysis was to evaluate the effects of recreational football on bone mineral density (BMD), bone mineral content (BMC) and bone turnover markers (BTM). Design: Systematic review and meta-analysis. Data Sources: MEDLINE, PubMed, SPORTDiscus, Web of Science, Cumulative Index to Nursing and Allied Health Literature (CINAHL) and Google Scholar were searched prior to September 2021. A manual database search was also performed using the following key terms, either singly or in combination: recreational football/soccer, street football/soccer, recreational small-sided games, effect, influence, impact, bone turnover markers, bone mineral density, bone turnover marker, bone health, osteogenesis, CTX, osteocalcin, P1NP. Eligibility Criteria for Selecting Studies: Randomised and matched controlled trials with participants allocated to a recreational football group or any other type of training intervention or passive control group were included. The primary outcome measures were total BMD, lower limb BMD, total BMC, lower limb BMC, osteocalcin, procollagen type 1N-terminal propeptide (P1NP) and collagen type 1 cross-linked C-telopeptide (CTX). A total of 17 papers met the inclusion criteria and were included. Statistical Analysis: Comprehensive Meta-analysis V.2 software (Biostat, Englewood, New Jersey, USA) was used for the meta-analyses. Risk of Bias: Agreement between the two reviewers was assessed using RoB2 tool and k statistics for full-text screening and rating of relevance and risk of bias. The k agreement rate between reviewers was k = 0.92. Results: The football interventions included were based on studies having a duration of 12–64 weeks with one 5-year follow-up study and with a training frequency of 1–3 sessions/wk. Training sessions were 45–60 min sessions of 3v3 – 7v7 small-sided games. The subjects covered an age span from 9 to 73 years. Five studies examined recreational football effects in females, nine studies in males and three studies included both sexes. Recreational football training produced a statistically significant effect (mean difference = 0.02 g/cm2, 95% confidence interval: 0.00–0.03, P = 0.02) on lower limb BMD and negligible effects for total BMD compared to no-exercise controls. The recreational football effects on total and lower limb BMC, when compared to both no-exercise controls and exercise controls, were negligible. A moderate to large significant increase in osteocalcin, P1NP and CTX was observed for recreational football compared to both no-exercise controls and exercise controls. Conclusion: In conclusion, recreational football training regimes lasting 12–64 weeks have a large osteogenic impact on bone turnover markers in comparison with no-exercise controls as well as exercise controls, and beneficial effects on lower limb BMD compared to no-exercise controls. Short and medium duration recreational football interventions have negligible effects on whole-body BMD and BMC (total and lower limb), with magnitudes similar to those of other exercise modes. [ABSTRACT FROM AUTHOR]

Gestational diabetes mellitus (GDM) poses a significant health concern for both mother and offspring. Exercise has emerged as a cornerstone of glycemic management in GDM. However, most research regarding this topic examines aerobic training (AT), despite substantial evidence for the effectiveness of resistance training (RT) in improving dysregulated glucose in other groups of people with diabetes, such as in type 2 diabetes mellitus (T2DM). Thus, the purpose of this paper is to review research that examined the impact of RT on markers of glucose management in GDM, and to discuss future research directions to determine the benefits of RT in GDM. Based on the current evidence, RT is effective in reducing insulin requirement, especially in overweight women, reducing fasting glucose concentrations, and improving short-term postprandial glycemic control. However, the number of studies and findings limit conclusions about the impact of RT on risk of GDM, fasting insulin concentrations, insulin resistance, β-cell function, and intra-exercise glucose management. Overall, current evidence is accumulating to suggest that RT is a promising non-pharmacological tool to regulate circulating glucose concentrations in women with GDM, and a potential alternative or supplement to AT. [ABSTRACT FROM AUTHOR]

Background: Analysis of lower limb exercises is traditionally completed with four distinct methods: (1) 3D motion capture; (2) depth-camera-based systems; (3) visual analysis from a qualified exercise professional; and (4) self-assessment. Each method is associated with a number of limitations.Objective: The aim of this systematic review is to synthesise and evaluate studies which have investigated the capacity for inertial measurement unit (IMU) technologies to assess movement quality in lower limb exercises.Data Sources: A systematic review of studies identified through the databases of PubMed, ScienceDirect and Scopus was conducted.Study Eligibility Criteria: Articles written in English and published in the last 10 years which investigated an IMU system for the analysis of repetition-based targeted lower limb exercises were included.Study Appraisal and Synthesis Methods: The quality of included studies was measured using an adapted version of the STROBE assessment criteria for cross-sectional studies. The studies were categorised into three groupings: exercise detection, movement classification or measurement validation. Each study was then qualitatively summarised.Results: From the 2452 articles that were identified with the search strategies, 47 papers are included in this review. Twenty-six of the 47 included studies were deemed as being of high quality.Conclusions: Wearable inertial sensor systems for analysing lower limb exercises is a rapidly growing field of research. Research over the past 10 years has predominantly focused on validating measurements that the systems produce and classifying users’ exercise quality. There have been very few user evaluation studies and no clinical trials in this field to date. [ABSTRACT FROM AUTHOR]

Background and Objective: Sedentary behaviors, defined as waking behaviors with low energy expenditure while sitting, are positively associated with several adverse health outcomes. However, the association between sedentary behaviors and blood pressure (BP) is inconclusive. This study aimed to conduct a systematic review and meta-analysis on the association between time spent in sedentary behaviors and BP. Methods: We searched PubMed, MEDLINE, and Web of Science for papers published before August 2014 that assessed the association between time spent in sedentary behaviors and BP. Studies on both adults and children were included. Only good quality studies were included. The pooled estimates of systolic BP (SBP) and diastolic BP (DBP) increase per hour of time spent in sedentary behaviors a day were computed using a fixed-effects model and a random-effects model, respectively. Another pooled estimate of odds ratio per hour of time spent in sedentary behaviors a day on having high BP was computed using a fixed-effects model. A sub-group analysis was conducted for studies using self-reported and objectively assessed time spent in sedentary behaviors separately. Results: A total of 31 papers of good quality were included in the systematic review, 18 of which found no association between time spent in sedentary behaviors and BP (58.1 %). A total of 28 papers were included in the meta-analysis. Pooled effects showed that an additional hour of time spent in sedentary behaviors per day was associated with an increase of 0.06 mmHg (108,228 participants, 95 % CI 0.01-0.11, p = 0.01) of SBP and 0.20 mmHg (107,791 participants, 95 % CI 0.10-0.29, p < 0.001) of DBP. Accelerometer-assessed time spent in sedentary behaviors was not associated with either SBP ( p = 0.06) or DBP ( p = 0.33). The odds ratio (OR) of having high BP with an additional hour of time spent in sedentary behaviors per day was 1.02 (98,798 participants, 95 % CI 1.003-1.03, p = 0.02). Conclusions: Self-reported but not accelerometer-assessed time spent in sedentary behaviors was associated with BP. Further studies are warranted to determine the preventive effect of reducing sedentary behaviors on high BP. [ABSTRACT FROM AUTHOR]

Background: Movement quality is typically assessed by drawing comparisons against predetermined movement standards. Movements are often discretely scored or labelled against pre-set criteria, though movement quality can also be evaluated using motion-related measurements (e.g., spatio-temporal parameters and kinematic variables). Wearable technology has the potential to measure and assess movement quality and offer valuable, practical feedback. Objectives: A systematic approach was taken to examine the benefits associated with multi-sensor and multiple wearable-device usage, compared with unimodal applications, when assessing movement quality. Consequently, this review considers the additional variables and features that could be obtained through multi-sensor devices for use in movement analyses. Processing methods and applications of the various configurations were also explored. Methods: Articles were included within this review if they were written in English, specifically studied the use of wearable sensors to assess movement quality, and were published between January 2010 and December 2022. Of the 62,635 articles initially identified, 27 papers were included in this review. The quality of included studies was determined using a modified Downs and Black checklist, with 24/27 high quality. Results: Fifteen of the 27 included studies used a classification approach, 11 used a measurement approach, and one used both methods. Accelerometers featured in all 27 studies, in isolation (n = 5), with a gyroscope (n = 9), or with both a gyroscope and a magnetometer (n = 13). Sampling frequencies across all studies ranged from 50 to 200 Hz. The most common classification methods were traditional feature-based classifiers (n = 5) and support vector machines (SVM; n = 5). Sensor fusion featured in six of the 16 classification studies and nine of the 12 measurement studies, with the Madgwick algorithm most prevalent (n = 7). Conclusions: This systematic review highlights the differences between the applications and processing methods associated with the use of unimodal and multi-sensor wearable devices when assessing movement quality. Further, the use of multiple devices appears to increase the feasibility of effectively assessing holistic movements, while multi-sensor devices offer the ability to obtain more output metrics. [ABSTRACT FROM AUTHOR]

Background: Running overuse injuries (ROIs) occur within a complex, partly injury-specific interplay between training loads and extrinsic and intrinsic risk factors. Biomechanical risk factors (BRFs) are related to the individual running style. While BRFs have been reviewed regarding general ROI risk, no systematic review has addressed BRFs for specific ROIs using a standardized methodology. Objective: To identify and evaluate the evidence for the most relevant BRFs for ROIs determined during running and to suggest future research directions. Design: Systematic review considering prospective and retrospective studies. (PROSPERO_ID: 236,832). Data Sources: PubMed. Connected Papers. The search was performed in February 2021. Eligibility Criteria: English language. Studies on participants whose primary sport is running addressing the risk for the seven most common ROIs and at least one kinematic, kinetic (including pressure measurements), or electromyographic BRF. A BRF needed to be identified in at least one prospective or two independent retrospective studies. BRFs needed to be determined during running. Results: Sixty-six articles fulfilled our eligibility criteria. Levels of evidence for specific ROIs ranged from conflicting to moderate evidence. Running populations and methods applied varied considerably between studies. While some BRFs appeared for several ROIs, most BRFs were specific for a particular ROI. Most BRFs derived from lower-extremity joint kinematics and kinetics were located in the frontal and transverse planes of motion. Further, plantar pressure, vertical ground reaction force loading rate and free moment-related parameters were identified as kinetic BRFs. Conclusion: This study offers a comprehensive overview of BRFs for the most common ROIs, which might serve as a starting point to develop ROI-specific risk profiles of individual runners. We identified limited evidence for most ROI-specific risk factors, highlighting the need for performing further high-quality studies in the future. However, consensus on data collection standards (including the quantification of workload and stress tolerance variables and the reporting of injuries) is warranted. [ABSTRACT FROM AUTHOR]

Background: Many variables related to sport have been shown to have circadian rhythms. Chronotype is the expression of circadian rhythmicity in an individual, and three categories of chronotype are defined: morning types (M-types), evening types (E-types), and neither types (N-types). M-types show earlier peaks of several psychophysiological variables during the day than E-types. The effect of chronotype on athletic performance has not been extensively investigated. Objective: The objective of the present review was to study the effect of chronotype on athletic performance and the psychophysiological responses to physical activity. Methods: The present review adheres to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) reporting guidelines. We searched PubMed, Scopus, and Web of Science for scientific papers using the keywords 'chronotype', 'circadian typology', 'morningness', and 'eveningness' in combination with each of the words 'sport', 'performance', and 'athletic.' Relevant reference lists were inspected. We limited the search results to peer-reviewed papers published in English from 1985 to 2015. Results: Ten papers met our inclusion criteria. Rating of perceived exertion and fatigue scores in relation to athletic performances are influenced by chronotype: M-types perceived less effort when performing a submaximal physical task in the morning than did N- and E-types. In addition, M-types generally showed better athletic performances, as measured by race times, in the morning than did N- and E-types. Other results concerning chronotype effect on physiological responses to physical activity were not always consistent: heterogeneous samples and different kinds of physical activity could partially explain these discrepancies. Conclusions: Sports trainers and coaches should take into account the influence of both the time of day and chronotype effect when scheduling training sessions into specific time periods. [ABSTRACT FROM AUTHOR]

Background: Australian football is a popular sport in Australia, at both the community and elite levels. It is a high-speed contact sport with a higher incidence of medically treated injuries when compared with most other organized sports. Hamstring injuries, ligament injuries to the knee or ankle, hip/groin injuries and tendinopathies are particularly common and often result in considerable time lost from sport. Consequently, the prevention of lower limb injuries is a priority for both community and elite Australian football organizations. There is considerable literature available on exercise programmes aimed at reducing lower limb injuries in Australian football and other running-related sports. The quality and outcomes of these studies have varied considerably, but indicate that exercise protocols may be an effective means of preventing lower limb injuries. Despite this, there has been limited high-quality and systematic evaluation of these data. Objective: The aim of this literature review is to systematically evaluate the evidence about the benefits of lower limb injury prevention exercise protocols aimed at reducing the most common severe lower limb injuries in Australian football. Methods: The Cochrane Central Register of Controlled Trials, the Cochrane Bone Joint and Muscle Trauma Group Specialized Register, MEDLINE and other electronic databases were searched, from January 1990 to December 2010. Papers reporting the results of randomized controlled trials (RCTs), quasi-RCTs, cohort and case-control studies were extracted. Primary outcomes were injury reduction or risk factor identification and/or modification. Secondary outcomes were adherence to any trialled interventions, injury severity and adverse effects such as secondary injuries and muscle soreness. The methodological quality of extracted manuscripts was assessed and results were collated. Results: Forty-seven papers were identified and reviewed of which 18 related to hamstring injury, eight related to knee or ankle ligament injury, five related to tendon injury and four were hip or groin injury related. Another 12 papers targeted general lower limb injuries. Most ( n = 27 [57 %]) were observational studies, investigating injury risk factors. Twenty reported the results of intervention trials. Of these, 15 were efficacy trials reporting the effects of an intervention in reducing injury rates, four were biomechanical interventions in which the impact of the intervention on a known injury risk factor was assessed and one reported changes in injury risk factors as well as injury rates. The strength of the evidence base for exercise programmes for lower limb injury prevention was found to be limited, primarily due to the research methods employed, low adherence to interventions by the study participants and a lack of statistical power. Limited evidence obtained from a small number of RCTs suggests that balance and control exercises might be efficacious in preventing ankle ligament injuries and a programme involving a combination of balance and control exercises, eccentric hamstring, plyometrics and strength exercises could be efficacious in preventing all lower limb injuries. Conclusions: Overall, the evidence for exercise programmes as an efficacious lower limb injury prevention strategy is predominantly restricted to studies addressing injury aetiology and mechanisms. The findings of this review highlight the need to develop and test interventions in well designed population-based trials with an emphasis on promoting intervention uptake and adherence and, hence, intervention effectiveness. The results of this review can inform the development of the components of a future lower limb injury prevention exercise protocol for community-level Australian football. [ABSTRACT FROM AUTHOR]

Background: Patellar tendinopathy (PT) is common and debilitating for jumping athletes. Intriguingly, despite its high prevalence and many research studies, a causal explanation for PT presence remains elusive. Objective: Our objective was to investigate whether landing biomechanics among jumping athletes are associated with PT and can predict onset. Methods: We conducted a systematic review with evidence gap map and meta-analysis. We searched three databases from inception to May 2021 for observational studies or trials evaluating landing biomechanics in jumping athletes with PT (JPTs). We assessed quality with a modified Downs and Black checklist, risk of bias with the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool, and evidence levels with van Tulder's criteria and provided an evidence gap map. Results: One prospective cohort (moderate quality), one cross-sectional cohort (moderate quality), and 14 case–control (four high-, seven moderate-, and three low-quality) studies, including 104 JPTs, 14 with previous PT, 45 with asymptomatic patellar tendon abnormality (PTA), and 190 controls were retained. All studies had a high risk of bias. Meta-analysis showed an association between lower ankle dorsiflexion and the presence of tendinopathy during drop and spike landings, and JPTs had reduced knee joint power and work during volleyball approach or drop landings (moderate evidence). Limited evidence suggested that JPTs had lower patellar tendon loads during drop landings. Strong or moderate evidence showed no relation between PT and sagittal plane peak knee and hip angles or range of motion; hip, knee, or ankle angles at initial contact (IC); knee angular velocities, peak trunk kinematics, or trunk angles at IC; sagittal plane hip, knee, or ankle moments; and peak vertical ground reaction force (vGRF) and vGRF impulse. Identified gaps were that no study simultaneously investigated athletes with previous PT, current PT, and PTA, and studies of joint angular velocities at IC, ankle and hip angular velocities after touchdown, leg stiffness, loading rate of forces, and muscle activation are lacking. Conclusion: Despite the voluminous literature, large number of participants, multitude of investigated parameters, and consistent research focus on landing biomechanics, only a few associations can be identified, such as reduced ankle dorsiflexion–plantarflexion range. Further, the quality of the existing literature is inadequate to draw strong conclusions, with only four high-quality papers being found. We were unable to determine biomechanical factors that predicted PT onset, as longitudinal/prospective studies enabling causal inference are absent. The identified gaps indicate useful areas in which to explore causal relationships to inform intervention development. Therefore, high-quality prospective studies are essential to definitively determine whether landing biomechanics play a part in the development, recurrence, or management of PT and represent a potential therapeutic or preventive target alongside non-biomechanical factors. [ABSTRACT FROM AUTHOR]

Background: The ability to monitor training load accurately in professional sports is proving vital for athlete preparedness and injury prevention. While numerous monitoring techniques have been developed to assess the running demands of many team sports, these methods are not well suited to throwing-dominant sports that are infrequently linked to high running volumes. Therefore, other techniques are required to monitor the differing demands of these sports to ensure athletes are adequately prepared for competition. Objective: To investigate the different methodologies used to quantitatively monitor training load in throwing-dominant sports. Methods: A systematic review of the methods used to monitor training load in throwing-dominant sports was conducted using variations of terms that described different load-monitoring techniques and different sports. Studies included in this review were published prior to June 2015 and were identified through a systematic search of four electronic databases including Academic Search Complete, CINAHL, Medline and SPORTDiscus. Only full-length peer-reviewed articles investigating workload monitoring in throwing-dominant sports were selected for review. Results: A total of 8098 studies were initially retrieved from the four databases and 7334 results were removed as they were either duplicates, review articles, non-peer-reviewed articles, conference abstracts or articles written in languages other than English. After screening the titles and abstracts of the remaining papers, 28 full-text papers were reviewed, resulting in the identification of 20 articles meeting the inclusion criteria for monitoring workloads in throwing-dominant sports. Reference lists of selected articles were then scanned to identify other potential articles, which yielded one additional article. Ten articles investigated workload monitoring in cricket, while baseball provided eight results, and handball, softball and water polo each contributed one article. Results demonstrated varying techniques used to monitor workload and purposes for monitoring workload, encompassing the relationship between workload and injury, individual responses to workloads, the effect of workload on subsequent performance and the future directions of workload-monitoring techniques. Conclusion: This systematic review highlighted a number of simple and effective workload-monitoring techniques implemented across a variety of throwing-dominant sports. The current literature placed an emphasis on the relationship between workload and injury. However, due to differences in chronological and training age, inconsistent injury definitions and time frames used for monitoring, injury thresholds remain unclear in throwing-dominant sports. Furthermore, although research has examined total workload, the intensity of workload is often neglected. Additional research on the reliability of self-reported workload data is also required to validate existing relationships between workload and injury. Considering the existing disparity within the literature, it is likely that throwing-dominant sports would benefit from the development of an automated monitoring tool to objectively assess throwing-related workloads in conjunction with well-established internal measures of load in athletes. [ABSTRACT FROM AUTHOR]

Background: The prevalence of doping in competitive sport, and the methods for assessing prevalence, remain poorly understood. This reduces the ability of researchers, governments, and sporting organizations to determine the extent of doping behavior and the impacts of anti-doping strategies. Objectives: The primary aim of this subject-wide systematic review was to collate and synthesize evidence on doping prevalence from published scientific papers. Secondary aims involved reviewing the reporting accuracy and data quality as evidence for doping behavior to (1) develop quality and bias assessment criteria to facilitate future systematic reviews; and (2) establish recommendations for reporting future research on doping behavior in competitive sports to facilitate better meta-analyses of doping behavior. Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used to identify relevant studies. Articles were included if they contained information on doping prevalence of any kind in competitive sport, regardless of the methodology and without time limit. Through an iterative process, we simultaneously developed a set of assessment criteria; and used these to assess the studies for data quality on doping prevalence, potential bias and reporting. Results: One-hundred and five studies, published between 1975 and 2019,were included. Doping prevalence rates in competitive sport ranged from 0 to 73% for doping behavior with most falling under 5%. To determine prevalence, 89 studies used self-reported survey data (SRP) and 17 used sample analysis data (SAP) to produce evidence for doping prevalence (one study used both SRP and SAP). In total, studies reporting athletes totaled 102,515 participants, (72.8% men and 27.2% women). Studies surveyed athletes in 35 countries with 26 involving athletes in the United States, while 12 studies examined an international population. Studies also surveyed athletes from most international sport federations and major professional sports and examined international, national, and sub-elite level athletes, including youth, masters, amateur, club, and university level athletes. However, inconsistencies in data reporting prevented meta-analysis for sport, gender, region, or competition level. Qualitative syntheses were possible and provided for study type, gender, and geographical region. The quality assessment of prevalence evidence in the studies identified 20 as "High", 60 as "Moderate", and 25 as "Low." Of the 89 studies using SRP, 17 rated as "High", 52 rated as "Moderate", and 20 rated as "Low." Of the 17 studies using SAP, 3 rated as "High", 9 rated as "Moderate", and 5 rated as "Low." Examining ratings by year suggests that both the quality and quantity of the evidence for doping prevalence in published studies are increasing. Conclusions: Current knowledge about doping prevalence in competitive sport relies upon weak and disparate evidence. To address this, we offer a comprehensive set of assessment criteria for studies examining doping behavior data as evidence for doping prevalence. To facilitate future evidence syntheses and meta-analyses, we also put forward "best practice" recommendations and reporting guidelines that will improve evidence quality. [ABSTRACT FROM AUTHOR]

Background: Microtechnology has allowed sport scientists to understand the locomotor demands of various sports. While wearable global positioning technology has been used to quantify the locomotor demands of sporting activities, microsensors (i.e. accelerometers, gyroscopes and magnetometers) embedded within the units also have the capability to detect sport-specific movements. Objective: The objective of this study was to determine the extent to which microsensors (also referred to as inertial measurement units and microelectromechanical sensors) have been utilised in quantifying sport-specific movements. Methods: A systematic review of the use of microsensors and associated terms to evaluate sport-specific movements was conducted; permutations of the terms used included alternate names of the various technologies used, their applications and different applied environments. Studies for this review were published between 2008 and 2014 and were identified through a systematic search of six electronic databases: Academic Search Complete, CINAHL, PsycINFO, PubMed, SPORTDiscus, and Web of Science. Articles were required to have used athlete-mounted sensors to detect sport-specific movements (e.g. rugby union tackle) rather than sensors mounted to equipment and monitoring generic movement patterns. Results: A total of 2395 studies were initially retrieved from the six databases and 737 results were removed as they were duplicates, review articles or conference abstracts. After screening titles and abstracts of the remaining papers, the full text of 47 papers was reviewed, resulting in the inclusion of 28 articles that met the set criteria around the application of microsensors for detecting sport-specific movements. Eight articles addressed the use of microsensors within individual sports, team sports provided seven results, water sports provided eight articles, and five articles addressed the use of microsensors in snow sports. All articles provided evidence of the ability of microsensors to detect sport-specific movements. Results demonstrated varying purposes for the use of microsensors, encompassing the detection of movement and movement frequency, the identification of movement errors and the assessment of forces during collisions. Conclusion: This systematic review has highlighted the use of microsensors to detect sport-specific movements across a wide range of individual and team sports. The ability of microsensors to capture sport-specific movements emphasises the capability of this technology to provide further detail on athlete demands and performance. However, there was mixed evidence on the ability of microsensors to quantify some movements (e.g. tackling within rugby union, rugby league and Australian rules football). Given these contrasting results, further research is required to validate the ability of wearable microsensors containing accelerometers, gyroscopes and magnetometers to detect tackles in collision sports, as well as other contact events such as the ruck, maul and scrum in rugby union. [ABSTRACT FROM AUTHOR]

Background: At the turn of the century, a new format of cricket [Twenty20 (T20)] was introduced that has led to more matches being played. Since then, it has been debated whether T20 cricket has increased the risk of overuse injuries.Objectives: The primary aim of this study was to meta-analyse the cricket injury rates in the twenty-first century. The secondary aims were to explore the risk factors and mechanisms of injury by analysing correlates such as age, format, era of play, country, player type, etc., and to conduct a qualitative analysis of the published studies.Methods: Several databases were searched using keywords “cricket” and “injur*” and 24 papers reporting cricket injuries fitted the inclusion criteria. Fifteen papers included data on exposure time and were used to calculate injury rates to perform sub-group analysis.Results: Pooled data on 12,511 players revealed 7627 injuries, and the 1.12 million hours of cricket play from 15 studies reporting exposure time showed an injury rate of 53.16 (95% confidence interval 51.84-54.52) per 10,000 h of play. There were no statistically significant differences in injury rates based on age, format, era of play, country, player type and injury definitions. Bowling biomechanics and workload were identified as the major risk factors for bowling injuries.Conclusions: This review shows that injury rates in junior and amateur cricket are higher than the injury rates of comparable cohorts playing other popular non-contact or quasi-contact team sports. There is not enough evidence to conclude that T20 cricket has increased injury rates. [ABSTRACT FROM AUTHOR]

An athlete’s pacing strategy is widely recognised as an essential determinant for performance during individual events. Previous research focussed on the importance of internal bodily state feedback, revealed optimal pacing strategies in time-trial exercise, and explored concepts such as teleoanticipation and template formation. Recently, human-environment interactions have additionally been emphasized as a crucial determinant for pacing, yet how they affect pacing is not well understood. Therefore, this literature review focussed on exploring one of the most important human-environment interactions in sport competitions: the interaction among competitors. The existing literature regarding the regulation of exercise intensity and the effect of competition on pacing and performance is critically reviewed in this paper. The PubMed, CINAHL and Web of Science electronic databases were searched for studies about pacing in sports and (interpersonal) competition between January 2000 to October 2017, using the following combination of terms: (1) Sports AND (2) Pacing, resulting in 75 included papers. The behaviour of opponents was shown to be an essential determinant in the regulation of exercise intensity, based on both observational (N = 59) and experimental (N = 16) studies. However, adjustment in the pacing response related to other competitors appears to depend on the competitive situation and the current internal state of the athlete. The findings of this review emphasize the importance of what is happening around the athlete for the outcome of the decision-making process involved in pacing, and highlight the necessity to incorporate human-environment interactions into models that attempt to explain the regulation of exercise intensity in sports and exercise. [ABSTRACT FROM AUTHOR]

Background: In recent years, there has been a large expansion in literature pertaining to the game of Australian football (AF). Furthermore, there have been a number of rule changes that are likely to have changed the demands of the game. Based on these advances and changes, it seemed important to conduct a review assessing the scientific literature surrounding the sport.Objective: The review evaluates the match demands of AF, the qualities required for success, and the impact training and competition have on adaptation, injury and fatigue.Methods: A systematic search of PubMed, CINAHL, SPORTDiscus, Web of Science and Scopus for AF literature was conducted; studies investigating match demands, physical qualities, training practices and injury were included. Weighted means and standard deviations were calculated for match demands and physical and anthropometric profiles across playing standards.Results: A total of 1830 articles were retrieved in the initial search, with 888 removed as duplicates, 626 removed for being non-relevant and a further 152 removed for being AF papers but not relevant to the review. As such, 164 AF papers were included in the review. Due to the intermittent high-intensity nature of match-play, players need a wide range of physical and technical qualities to excel, with speed, aerobic fitness, reactive agility and well-developed lean mass being central to success. Training for AF at the elite level is associated with high workloads, with players engaging in numerous training modalities; even altitude and heat training camps have been utilised by Australian Football League (AFL) teams to further augment fitness improvements. While high chronic workloads can be tolerated and are needed for improving physical qualities, careful planning and monitoring of internal and external workloads is required to minimise sharp spikes in load that are associated with injury.Conclusions: There is a complex interaction between numerous contextual factors that influence the match demands that are discussed in this review. Whilst players must have the physical capacities to cope with the intense physical demands of AF matches, the successful execution of technical skills during match-play is central to success. To develop these skills and attributes, specific and carefully planned and monitored training must be performed over a number of years. [ABSTRACT FROM AUTHOR]

Background: In a previous meta-analysis including nine trials comparing aerobic interval training with aerobic continuous training in patients with coronary artery disease, we found a significant difference in peak oxygen uptake favoring aerobic interval training.Objective: The objective of this study was to (1) update the original meta-analysis focussing on peak oxygen uptake and (2) evaluate the effect on secondary outcomes.Methods: We conducted a systematic review with a meta-analysis by searching PubMed and SPORTDiscus databases up to March 2017. We included randomized trials comparing aerobic interval training and aerobic continuous training in patients with coronary artery disease or chronic heart failure. The primary outcome was change in peak oxygen uptake. Secondary outcomes included cardiorespiratory parameters, cardiovascular risk factors, cardiac and vascular function, and quality of life.Results: Twenty-four papers were identified (n = 1080; mean age 60.7 ± 10.7 years). Aerobic interval training resulted in a higher increase in peak oxygen uptake compared with aerobic continuous training in all patients (1.40 mL/kg/min; p < 0.001), and in the subgroups of patients with coronary artery disease (1.25 mL/kg/min; p = 0.001) and patients with chronic heart failure with reduced ejection fraction (1.46 mL/kg/min; p = 0.03). Moreover, a larger increase of the first ventilatory threshold and peak heart rate was observed after aerobic interval training in all patients. Other cardiorespiratory parameters, cardiovascular risk factors, and quality of life were equally affected.Conclusion: This meta-analysis adds further evidence to the clinically significant larger increase in peak oxygen uptake following aerobic interval training vs. aerobic continuous training in patients with coronary artery disease and chronic heart failure. More well-designed randomized controlled trials are needed to establish the safety of aerobic interval training and the sustainability of the training response over longer periods. [ABSTRACT FROM AUTHOR]

Background: The Covid-19 pandemic is affecting the entire world population. During the first spread, most governments have implemented quarantine and strict social distancing procedures. Similar measures during recent pandemics resulted in an increase in post-traumatic stress, anxiety and depression symptoms. The development of novel interventions to mitigate the mental health burden are of utmost importance. Objective: In this rapid review, we aimed to provide a systematic overview of the literature with regard to associations between physical activity (PA) and depression and anxiety during the COVID-19 pandemic. Data Source: We searched major databases (PubMed, EMBASE, SPORTDiscus, and Web of Science) and preprint servers (MedRxiv, SportRxiv, ResearchGate, and Google Scholar), for relevant papers up to 25/07/2020. Study Eligibility Criteria: We included observational studies with cross-sectional and longitudinal designs. To qualify for inclusion in the review, studies must have tested the association of PA with depression or anxiety, using linear or logistic regressions. Depression and anxiety must have been assessed using validated rating scales. Study Appraisal and Synthesis Methods: Effect sizes were represented by fully adjusted standardized betas and odds ratios (OR) alongside 95% confidence intervals (CI). In case standardized effects could not be obtained, unstandardized effects were presented and indicated. Results: We identified a total of 21 observational studies (4 longitudinal, 1 cross-sectional with retrospective analysis, and 16 cross-sectional), including information of 42,293 (age 6–70 years, median female = 68%) participants from five continents. The early evidence suggests that people who performed PA on a regular basis with higher volume and frequency and kept the PA routines stable, showed less symptoms of depression and anxiety. For instance, those reporting a higher total time spent in moderate to vigorous PA had 12–32% lower chances of presenting depressive symptoms and 15–34% of presenting anxiety. Conclusion: Performing PA during Covid-19 is associated with less depression and anxiety. To maintain PA routines during Covid-19, specific volitional and motivational skills might be paramount to overcome Covid-19 specific barriers. Particularly, web-based technologies could be an accessible way to increase motivation and volition for PA and maintain daily PA routines. [ABSTRACT FROM AUTHOR]

Background: Hamstrings neuromuscular function is a crucial component of functional movement, and changes after anterior cruciate ligament (ACL) injury contribute to risk factors for secondary injury and long-term sequelae. To effectively treat muscular impairments, an accurate understanding of hamstrings neuromuscular function in patients with ACL reconstruction (ACLR) is needed. Objective: A systematic review and meta-analysis were undertaken to describe and quantify hamstrings neuromuscular function in individuals with ACLR compared to controls. Methods: We searched PubMed, Web of Science, SPORTDiscus, CINAHL, and EBSCOhost databases in October of 2020 for studies evaluating the difference between hamstrings electromyography (EMG) between individuals with ACLR and controls. Two independent reviewers assessed each paper for inclusion and quality. Means and standard deviations were extracted from each included study to allow random-effect size (ES) meta-analysis calculations for comparison of results. Results: Thirty-four studies were included for final review. From these, 5 categories of neuromuscular outcomes were identified, and studies were grouped accordingly: (1) muscle activation levels (EMG amplitude), (2) co-activation, (3) onset timing, (4) electromechanical delay, and (5) time-to-peak activity. Moderate to strong evidence indicates that individuals with ACLR demonstrate higher hamstrings EMG amplitude (normalized to % maximum voluntary isometric contraction) and hamstrings-to-quadriceps co-activation during gait and stair ambulation compared to controls. In addition, there was moderate evidence of longer electromechanical delay during knee flexion and greater hamstrings-to-quadriceps co-activation during knee extension compared to controls. Conclusions: Greater hamstrings EMG amplitude and co-activation during gait and ambulation tasks and longer electromechanical delay of the hamstrings in individuals with ACLR align with clinical impairments following ACLR and have implications for re-injury risk and long-term joint health, thus warranting attention in rehabilitation. [ABSTRACT FROM AUTHOR]

Background: Hamstrings muscle morphology is determinant of muscle function (i.e. strength). Among individuals with ACL reconstruction (ACLR), less cross-sectional area (CSA) and volume in the ACLR-limb are associated with muscle weakness, and may contribute to lower rates of return to preinjury activity level and an increased risk for long-term sequelae. Objectives: To effectively treat muscular impairments, an accurate understanding of differences in hamstrings morphology following ACLR is needed. A systematic review and meta-analysis were undertaken to describe the morphology of the hamstring muscle complex after ACLR. Methods: We searched five databases for studies evaluating the difference between hamstrings size and architecture in individuals with ACLR. Two independent reviewers assessed each paper for inclusion and quality. Means and standard deviations were extracted from each included study to allow fixed-effect size meta-analysis calculations for comparison of results. Results: Twenty-four studies were included for final review. Eight categories of morphological outcomes were identified, and studies were grouped accordingly: (1) volume, (2) cross-sectional area (CSA), (3) muscle length, (4) muscle thickness, (5) fascicle length, (6) pennation angle, (7) fiber area, and (8) fiber type. Meta-analysis demonstrated lower hamstrings volume in the ACLR-limb in both contralateral and control group comparisons, and lower CSA, length, and thickness in the ACLR-limb in contralateral comparisons. The semitendinosus and gracilis were most profoundly impacted. Limited moderate evidence demonstrated greater biceps femoris pennation angle in the ACLR-limb. Conclusions: Individuals with ACLR demonstrated large deficits in semitendinosus and gracilis muscle CSA and volume in the ACLR-limb compared contralaterally, with no differences observed in the biceps femoris or semimembranosus. Clinical implications regarding assessment and treatment of individuals with ACLR are discussed. [ABSTRACT FROM AUTHOR]

Background: Team ball sports such as soccer, basketball and volleyball have high participation levels worldwide. Musculoskeletal injuries are common in team ball sports and are associated with significant treatment costs, participation loss and long-term negative side effects. The results of recent randomized controlled trials provide support for the protective effect of injury-prevention exercise programmes (IPEPs) in team ball sports, but also highlight that achieving adequate compliance can be challenging. A key process in enhancing the ultimate impact of team ball sport IPEPs is identifying the specific implementation components that influence the adoption, execution and maintenance of these interventions. Despite this, no systematic review focussing on the specific implementation components of team ball sport IPEPs has been conducted. Objectives: Our objective was to assess the reporting of specific implementation components in the published literature on team ball sport IPEPs using the Reach Efficacy Adoption Implementation Maintenance (RE-AIM) framework. Methods: Six electronic databases were systematically searched from inception to December 2012 for papers reporting team ball sport IPEP trials. All eligible papers were independently evaluated by two raters before reaching consensus on the reporting of individual RE-AIM items, using the RE-AIM Model Dimension Items Checklist (RE-AIM MDIC). Results: A total of 60 papers, reporting 52 unique intervention trials, met eligibility criteria. Before consensus, the level of agreement across all trials between reviewers using the RE-AIM MDIC ranged from 81 to 91 %. The RE-AIM MDIC dimension of 'efficacy' had the highest level of reporting, with the five individual items in this dimension reported in 19-100 % of eligible trials (mean 58 %). The RE-AIM MDIC dimension 'maintenance-setting level' had the lowest level of reporting, with none of the four individual items in this dimension reported. For other dimensions, the mean level of reporting and range across items were 'reach' 34 % (12-60 %); 'adoption-setting level' 1 % (0-2 %); 'adoption-delivery agent level' 7 % (4-10 %); 'implementation' 36 % (13-63 %) and 'maintenance individual level' 1 % (0-4 %). Conclusion: Information on the specific implementation components of team ball sport IPEPs in published studies is scarce. In particular, major reporting gaps exist regarding the adoption and maintenance of these programmes. The RE-AIM MDIC can be successfully applied to reviewing literature in this context. [ABSTRACT FROM AUTHOR]

Background: Measuring the physical work and resultant acute psychobiological responses of basketball can help to better understand and inform physical preparation models and improve overall athlete health and performance. Recent advancements in training load monitoring solutions have coincided with increases in the literature describing the physical demands of basketball, but there are currently no reviews that summarize all the available basketball research. Additionally, a thorough appraisal of the load monitoring methodologies and measures used in basketball is lacking in the current literature. This type of critical analysis would allow for consistent comparison between studies to better understand physical demands across the sport. Objectives: The objective of this systematic review was to assess and critically evaluate the methods and technologies used for monitoring physical demands in competitive basketball athletes. We used the term 'training load' to encompass the physical demands of both training and game activities, with the latter assumed to provide a training stimulus as well. This review aimed to critique methodological inconsistencies, establish operational definitions specific to the sport, and make recommendations for basketball training load monitoring practice and reporting within the literature. Methods: A systematic review of the literature was performed using EBSCO, PubMed, SCOPUS, and Web of Science to identify studies through March 2020. Electronic databases were searched using terms related to basketball and training load. Records were included if they used a competitive basketball population and incorporated a measure of training load. This systematic review was registered with the International Prospective Register of Systematic Reviews (PROSPERO Registration # CRD42019123603), and approved under the National Basketball Association (NBA) Health Related Research Policy. Results: Electronic and manual searches identified 122 papers that met the inclusion criteria. These studies reported the physical demands of basketball during training (n = 56), competition (n = 36), and both training and competition (n = 30). Physical demands were quantified with a measure of internal training load (n = 52), external training load (n = 29), or both internal and external measures (n = 41). These studies examined males (n = 76), females (n = 34), both male and female (n = 9), and a combination of youth (i.e. under 18 years, n = 37), adults (i.e. 18 years or older, n = 77), and both adults and youth (n = 4). Inconsistencies related to the reporting of competition level, methodology for recording duration, participant inclusion criteria, and validity of measurement systems were identified as key factors relating to the reporting of physical demands in basketball and summarized for each study. Conclusions: This review comprehensively evaluated the current body of literature related to training load monitoring in basketball. Within this literature, there is a clear lack of alignment in applied practices and methodological framework, and with only small data sets and short study periods available at this time, it is not possible to draw definitive conclusions about the true physical demands of basketball. A detailed understanding of modern technologies in basketball is also lacking, and we provide specific guidelines for defining and applying duration measurement methodologies, vetting the validity and reliability of measurement tools, and classifying competition level in basketball to address some of the identified knowledge gaps. Creating alignment in best-practice basketball research methodology, terminology and reporting may lead to a more robust understanding of the physical demands associated with the sport, thereby allowing for exploration of other research areas (e.g. injury, performance), and improved understanding and decision making in applying these methods directly with basketball athletes. [ABSTRACT FROM AUTHOR]

Background: Self-reported outcome measures of athlete health, wellbeing and performance add information to that obtained from clinical measures. However valid, universally accepted outcome measures are required. Objective: To determine which athlete-reported outcome measures of performance have been used to measure the impact of injury and illness on performance in sport and assess evidence to support their validity. Methods: The authors searched Ovid MEDLINE, Ovid EMBASE, CINAHL Plus, SPORTDiscus with Full Text and Cochrane library to January 2016. Predefined inclusion and exclusion criteria were applied and papers included if an outcome measure of performance, assessed in relation to illness, injury or a related intervention, was reported by an elite, adult, able-bodied athlete. A checklist was used to assess eligible outcome measures for aspects of validity. Reporting of this study was guided by PRISMA guidelines for systematic reviews. Results: Twenty athlete-reported outcome measures in 21 papers were identified. Of these 20, only four cited validation. Of these four, three reported evidence to support validity in elite athlete groups as defined by the predetermined checklist. Fifteen patient-reported outcome measures were identified, of which four demonstrated validity in young athletic populations. Conclusions: Most athlete-reported outcome measures of performance have been designed for individual studies with no reported assessment of validity. Despite some limitations, the Oslo Sports Trauma Centre overuse injury questionnaire demonstrates validity and potential utility to investigate the self-reported impact of pre-defined conditions on athletic performance across different sports. [ABSTRACT FROM AUTHOR]

Background: The ActivityStat hypothesis suggests that when physical activity is increased or decreased in one domain, there will be a compensatory change in another domain, in order to maintain an overall stable level of physical activity or energy expenditure over time. The ActivityStat debate is gaining momentum in the literature and most of the research to date is based on observational studies. Objective: The objective of this paper is to conceptually clarify the ActivityStat hypothesis and to examine the experimental research aiming to demonstrate or refute compensation using a systematic review process. Methods: A systematic review was conducted using electronic database searches with the aim of detecting studies experimentally investigating the ActivityStat hypothesis or compensation in physical activity or energy expenditure. Included studies were critically appraised using a specifically designed tool to address the conceptual considerations of the ActivityStat hypothesis. Results: Searches identified 28 studies that met the inclusion criteria. Publications spanned 26 years and had multiple methodological approaches, including randomized and non-randomized controlled trials, crossover designs, cluster randomized controlled trials and pre-post trials. Populations of the included studies ranged from children, to adults and the elderly, across a range of weight statuses and used both aerobic, resistance and mixed-exercise interventions. The timeframe of interventions ranged from 1 day to 4 years and outcomes were measured using doubly labelled water, accelerometry, heart rate monitoring, resting metabolic rate, indirect calorimetry, pedometry, subjective recall questionnaire and the activity-related time index. Fifteen of 28 included studies provided evidence of compensation, while 13 did not. Subgroup analyses by population, type and duration of intervention, weight status and study quality also showed mixed findings. Conclusion: There is a substantial body of experimental literature investigating compensation that has largely been overlooked in the ActivityStat debate. However, this evidence is currently inconclusive and lacks a cohesive approach to the question of an ActivityStat. Recommendations for the design of future experimental research investigating the ActivityStat hypothesis are presented. [ABSTRACT FROM AUTHOR]

Background: Acute fatigue is hypothesized to alter lower extremity injury risk profiles by affecting intrinsic risk factors (i.e. single leg postural control, hamstring strength). However, no systematic overview exists that merges the insights into prospective lower extremity injury risk profiling with the effect of acute fatigue on functional test performance. Objective: The objective of this review is to identify the influence of acute fatigue on prospectively determined modifiable intrinsic risk factors for lower extremity injuries. Design: Systematic review. Methods: PubMed (MEDLINE), Web of Science, PEDro, and Cochrane Library were searched until 29 May 2019. Studies were eligible when the study outcomes encompassed intrinsic modifiable risk factors for lower extremity injury, an acute fatigue intervention, and included healthy athletes or physically active people. Intrinsic modifiable risk factors were identified through recent systematic reviews and meta-analyses, and the referenced original research papers were used to determine outcome measures associated with increased injury risk. Results: Forty-three studies reported acute fatigue effects on modifiable risk factors, with eight studies matching all criteria for data-extraction. Acute fatigue can decrease single leg postural control, decrease ankle joint position sense, decrease isokinetic strength of hamstring and quadriceps muscles and can affect isokinetic hamstring:quadriceps ratios. Conclusion: Acute fatigue affects prospective intrinsic modifiable risk factors for lower extremity injury, indicating an altered injury risk profile for lateral ankle sprain, patellofemoral pain syndrome and hamstring injuries. Future research should allow for individual fatiguability as a relevant outcome, and merge insights from athlete-centred injury risk profiling and fatigue. [ABSTRACT FROM AUTHOR]

Background: Several studies investigated the effects of caffeine supplementation on movement velocity in resistance exercise. However, these studies presented inconsistent findings. Objective: This paper aimed to: (a) review the studies that explored the effects of caffeine supplementation on movement velocity in resistance exercise; and (b) pool their results using a meta-analysis. Methods: A search for studies was performed through seven databases. Random-effects meta-analyses of standardized mean differences (SMD) were performed to analyze the data. Sub-group meta-analyses explored the effects of caffeine on different velocity variables (i.e., mean and peak velocity), different loads (i.e., low, moderate, and high loads), and upper- and lower-body exercises. Results: Twelve studies met the inclusion criteria. In the main meta-analysis, in which we pooled all available studies, the SMD favored the caffeine condition (SMD = 0.62; 95% confidence interval [CI]: 0.39–0.84; p < 0.001). Sub-group analyses indicated that caffeine significantly enhances mean (SMD = 0.80; 95% CI: 0.48–1.12; p < 0.001) and peak velocity (SMD = 0.41; 95% CI: 0.08–0.75; p = 0.014), movement velocity with low loads (SMD = 0.78; 95% CI: 0.41–1.14; p < 0.001), moderate loads (SMD = 0.58; 95% CI: 0.25–0.91; p = 0.001), and high loads (SMD = 0.70; 95% CI: 0.33–1.07; p < 0.001), as well as in lower-body (SMD = 0.82; 95% CI: 0.42–1.23; p < 0.001) and upper-body exercises (SMD = 0.59; 95% CI: 0.37–0.82; p < 0.001). Conclusion: Acute caffeine supplementation is highly ergogenic for movement velocity in resistance exercise. Sub-group analyses indicated that caffeine ingestion is ergogenic: (a) for both mean and peak velocity; (b) for movement velocity when exercising with low, moderate and high loads, and (c) for movement velocity in both lower- and upper-body exercises. Previous meta-analyses that explored the effects of caffeine on various aspects of resistance exercise performance (i.e., muscular strength and endurance) reported trivial to moderate ergogenic effects (effect size range: 0.16–0.38). In the present meta-analysis, the pooled effect size ranged from 0.41 to 0.82. From a resistance exercise performance standpoint, this suggests that caffeine has the most pronounced performance-enhancing effects on movement velocity. [ABSTRACT FROM AUTHOR]

Background: Physical activity (PA) breaks in sitting time might attenuate metabolic markers relevant to the prevention of type 2 diabetes. Objectives: The primary aim of this paper was to systematically review and meta-analyse trials that compared the effects of breaking up prolonged sitting with bouts of PA throughout the day (INT) versus continuous sitting (SIT) on glucose, insulin and triacylglycerol (TAG) measures. A second aim was to compare the effects of INT versus continuous exercise (EX) on glucose, insulin and TAG measures. Methods: The review followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) recommendations. Eligibility criteria consisted of trials comparing INT vs. SIT or INT vs. one bout of EX before or after sitting, in participants aged 18 or above, who were classified as either metabolically healthy or impaired, but not with other major health conditions such as chronic obstructive pulmonary disease or peripheral arterial disease. Results: A total of 42 studies were included in the overall review, whereas a total of 37 studies were included in the meta-analysis. There was a standardised mean difference (SMD) of − 0.54 (95% CI − 0.70, − 0.37, p = 0.00001) in favour of INT compared to SIT for glucose. With respect to insulin, there was an SMD of − 0.56 (95% CI − 0.74, − 0.38, p = 0.00001) in favour of INT. For TAG, there was an SMD of − 0.26 (95% CI − 0.44, − 0.09, p = 0.002) in favour of INT. Body mass index (BMI) was associated with glucose responses (β = − 0.05, 95% CI − 0.09, − 0.01, p = 0.01), and insulin (β = − 0.05, 95% CI − 0.10, − 0.006, p = 0.03), but not TAG (β = 0.02, 95% CI − 0.02, 0.06, p = 0.37). When energy expenditure was matched, there was an SMD of − 0.26 (95% CI − 0.50, − 0.02, p = 0.03) in favour of INT for glucose, but no statistically significant SMDs for insulin, i.e. 0.35 (95% CI − 0.37, 1.07, p = 0.35), or TAG i.e. 0.08 (95% CI − 0.22, 0.37, p = 0.62). It is worth noting that there was possible publication bias for TAG outcomes when PA breaks were compared with sitting. Conclusion: The use of PA breaks during sitting moderately attenuated post-prandial glucose, insulin, and TAG, with greater glycaemic attenuation in people with higher BMI. There was a statistically significant small advantage for PA breaks over continuous exercise for attenuating glucose measures when exercise protocols were energy matched, but no statistically significant differences for insulin and TAG. PROSPERO Registration: CRD42017080982. PROSPERO Registration: CRD42017080982. [ABSTRACT FROM AUTHOR]

Background and Objective: Meta-analysis and meta-regression are often highly cited and may influence practice. Unfortunately, statistical errors in meta-analyses are widespread and can lead to flawed conclusions. The purpose of this article was to review common statistical errors in meta-analyses and to document their frequency in highly cited meta-analyses from strength and conditioning research. Methods: We identified five errors in one highly cited meta-regression from strength and conditioning research: implausible outliers; overestimated effect sizes that arise from confusing standard deviation with standard error; failure to account for correlated observations; failure to account for within-study variance; and a focus on within-group rather than between-group results. We then quantified the frequency of these errors in 20 of the most highly cited meta-analyses in the field of strength and conditioning research from the past 20 years. Results: We found that 85% of the 20 most highly cited meta-analyses in strength and conditioning research contained statistical errors. Almost half (45%) contained at least one effect size that was mistakenly calculated using standard error rather than standard deviation. In several cases, this resulted in obviously wrong effect sizes, for example, effect sizes of 11 or 14 standard deviations. Additionally, 45% failed to account for correlated observations despite including numerous effect sizes from the same study and often from the same group within the same study. Conclusions: Statistical errors in meta-analysis and meta-regression are common in strength and conditioning research. We highlight five errors that authors, editors, and readers should check for when preparing or critically reviewing meta-analyses. [ABSTRACT FROM AUTHOR]

Background: The high prevalence of injury amongst cricket fast bowlers exposes a great need for research into the risk factors associated with injury. Both extrinsic (environment-related) and intrinsic (person-related) risk factors are likely to be implicated within the high prevalence of non-contact injury amongst fast bowlers in cricket. Identifying and defining the relative importance of these risk factors is necessary in order to optimize injury prevention efforts. Objective: The objective of this review was to assess and summarize the scientific literature related to the extrinsic and intrinsic factors associated with non-contact injury inherent to adult cricket fast bowlers. Method: A systematic review was performed in compliance with the PRISMA guidelines. This review considered both experimental and epidemiological study designs. Studies that included male cricket fast bowlers aged 18 years or above, from all levels of play, evaluating the association between extrinsic/intrinsic factors and injury in fast bowlers were considered for inclusion. The three-step search strategy aimed at finding both published and unpublished studies from all languages. The searched databases included MEDLINE via PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), the Cochrane Controlled Trials Register in the Cochrane Library, Physiotherapy Evidence Database (PEDro), ProQuest 5000 International, ProQuest Health and Medical Complete, EBSCO MegaFile Premier, Science Direct, SPORTDiscus with Full Text and SCOPUS (prior to 28 April 2015). Initial keywords used were 'cricket', 'pace', 'fast', 'bowler', and 'injury'. Papers which fitted the inclusion criteria were assessed by two independent reviewers for methodological validity prior to inclusion in the review using standardized critical appraisal instruments from the Joanna Briggs Institute Meta Analysis of Statistics Assessment and Review Instrument (JBI-MAStARI). Results: A total of 16 studies were determined to be suitable for inclusion in this systematic review. The mean critical appraisal score of the papers included in this study was 6.88 (SD 1.15) out of a maximum of 9. The following factors were found to be associated with injury: bowling shoulder internal rotation strength deficit, compromised dynamic balance and lumbar proprioception (joint position sense), the appearance of lumbar posterior element bone stress, degeneration of the lumbar disc on magnetic resonance imaging (MRI), and previous injury. Conflicting results were found for the association of quadratus lumborum (QL) muscle asymmetry with injury. Technique-related factors associated with injury included shoulder-pelvis flexion-extension angle, shoulder counter-rotation, knee angle, and the proportion of side-flexion during bowling. Bowling workload was the only extrinsic factor associated with injury in adult cricket fast bowlers. A high bowling workload (particularly if it represented a sudden upgrade from a lower workload) increased the subsequent risk to sustaining an injury 1, 3 or 4 weeks later. Conclusion: Identifying the factors associated with injury is a crucial step which should precede the development of, and research into, the effectiveness of injury prevention programs. Once identified, risk factors may be included in pre-participation screening tools and injury prevention programs, and may also be incorporated in future research projects. Overall, the current review highlights the clear lack of research on factors associated with non-contact injury, specifically in adult cricket fast bowlers. Systematic review registration number Johanna Briggs Institute Database of Systematic Reviews and Implementation Reports 1387 (Olivier et al., JBI Database Syst Rev Implement Rep 13(1):3-13. doi:, ). [ABSTRACT FROM AUTHOR]

Background: A return to running after anterior cruciate ligament reconstruction (ACL-R) is critical to the clinical success of any cutting and pivoting athlete who wishes to return to sport. Knowledge of specific alterations during running after ACL-R is required to optimise rehabilitation for improving outcomes and long-term disability. Objective: The objective of this systematic review was to summarise kinematic, kinetic and muscle activation data during running after ACL-R and the intrinsic factors (e.g. surgical technique and strength asymmetries) affecting running biomechanics. Methods: MEDLINE, EMBASE, SPORTDiscus and CINAHL databases were searched from inception to 10 December, 2018. The search identified studies comparing kinematic, kinetic or muscle activation data during running between the involved limb and contralateral or control limbs. Studies analysing the effect of intrinsic factors in the ACL-R group were also included. Risk of bias was assessed, qualitative and quantitative analyses performed, and levels of evidence determined. Results: A total of 1993 papers were identified and 25 were included for analysis. Pooled analyses reported a deficit of knee flexion motion and internal knee extension moment, compared with both contralateral or control limbs, during the stance phase of running from 3 months to 5 years after ACL-R (strong evidence). Inconsistent results were found for both peak vertical ground reaction force and impact forces after ACL-R. Patellofemoral and tibiofemoral joint contact forces differed from both contralateral or control limbs up until at least 2.5 years after ACL-R and moderate evidence indicated no difference for muscle activations during moderate speed running. Quadriceps and hamstring strength asymmetries, and knee function, but not surgical techniques, were likely to be associated with both knee kinematics and kinetics during running after ACL-R. Conclusion: After ACL-R, knee flexion motion and internal knee extension moment are the most affected variables and are consistently smaller in the injured limb during running when pooling evidence. Clinicians should be aware that these deficits do not appear to resolve with time and, thus, specific clinical interventions may be needed to reduce long-term disability. Systematic review registration: Registered in PROSPERO 2017, CRD42017077130. [ABSTRACT FROM AUTHOR]

The physiological demands of marathon and ultra-marathon running are substantial, affecting multiple body systems. There have been several reviews on the physiological contraindications of participation; nevertheless, the respiratory implications have received relatively little attention. This paper provides an up-to-date review of the literature pertaining to acute pulmonary and respiratory muscle responses to marathon and ultra-marathon running. Pulmonary function was most commonly assessed using spirometry, with infrequent use of techniques including single-breath rebreathe and whole-body plethysmography. All studies observed statistically significant post-race reductions in one-or-more metrics of pulmonary function, with or without evidence of airway obstruction. Nevertheless, an independent analysis revealed that post-race values rarely fell below the lower-limit of normal and are unlikely, therefore, to be clinically significant. This highlights the virtue of healthy baseline parameters prior to competition and, although speculative, there may be more potent clinical manifestations in individuals with below-average baseline function, or those with pre-existing respiratory disorders (e.g., asthma). Respiratory muscle fatigue was most commonly assessed indirectly using maximal static mouth-pressure manoeuvres, and respiratory muscle endurance via maximum voluntary ventilation (MVV12). Objective nerve-stimulation data from one study, and others documenting the time-course of recovery, implicate peripheral neuromuscular factors as the mechanism underpinning such fatigue. Evidence of respiratory muscle fatigue was more prevalent following marathon compared to ultra-marathon, and might be a factor of work rate, and thus exercise ventilation, which is tempered during longer races. Potential implications of respiratory muscle fatigue on health and marathon/ultra-marathon performance have been discussed, and include a diminished postural stability that may increase the risk of injury when running on challenging terrain, and possible respiratory muscle fatigue-induced effects on locomotor limb blood flow. This review provides novel insights that might influence marathon/ultra-marathon preparation strategies, as well as inform medical best-practice of personnel supporting such events. [ABSTRACT FROM AUTHOR]

Background: Recent advances in mobile sensing and computing technology have provided a means to objectively and unobtrusively quantify postural control. This has resulted in the rapid development and evaluation of a series of wearable inertial sensor-based assessments. However, the validity, reliability and clinical utility of such systems is not fully understood. Objectives: This systematic review aims to synthesise and evaluate studies that have investigated the ability of wearable inertial sensor systems to validly and reliably quantify postural control performance in sports science and medicine applications. Methods: A systematic search strategy utilising the PRISMA guidelines was employed to identify eligible articles through ScienceDirect, Embase and PubMed databases. In total, 47 articles met the inclusion criteria and were evaluated and qualitatively synthesised under two main headings: measurement validity and measurement reliability. Furthermore, studies that investigated the utility of these systems in clinical populations were summarised and discussed. Results: After duplicate removal, 4374 articles were identified with the search strategy, with 47 papers included in the final review. In total, 28 studies investigated validity in healthy populations, and 15 studies investigated validity in clinical populations; 13 investigated the measurement reliability of these sensor-based systems. Conclusions: The application of wearable inertial sensors for sports science and medicine postural control applications is an evolving field. To date, research has primarily focused on evaluating the validity and reliability of a heterogeneous set of assessment protocols, in a laboratory environment. While researchers have begun to investigate their utility in clinical use cases such as concussion and musculoskeletal injury, most studies have leveraged small sample sizes, are of low quality and use a variety of descriptive variables, assessment protocols and sensor-mounting locations. Future research should evaluate the clinical utility of these systems in large high-quality prospective cohort studies to establish the role they may play in injury risk identification, diagnosis and management. This systematic review was registered with the International Prospective Register of Systematic Reviews on 10 August 2018 (PROSPERO registration: CRD42018106363): https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=106363. [ABSTRACT FROM AUTHOR]

Background: To date, athletic performance has been extensively assessed in youth soccer players through laboratory and field testing. Only recently has running performance via time-motion analysis been assessed during match play. Match running data are often useful in a practical context to aid game understanding and decision making regarding training content and prescriptions. A plethora of previous reviews have collated and appraised the literature on time-motion analysis in professional senior players, but none have solely examined youth players.Objective: The aim of the present systematic review was to provide a critical appraisal and summary of the original research articles that have evaluated match running performance in young male soccer players.Methods: Following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement, literature searches were performed in four databases: PubMed, ISI Web of Science, SPORTDiscus and SciELO. We used the following descriptors: soccer, football, young, youth, junior, physical performance, running performance, match running performance, movement patterns, time-motion analysis, distances covered, activity profile, work rate, match analysis, and match performance. Articles were included only if they were original articles written in the English language, studied populations of male children and/or adolescents (aged ≤ 20 years), were published/ahead of print on or before 31 December 2017 and showed at least one outcome measure regarding match running performance, such as total distance covered, peak game speed or indicators of activities performed at established speed thresholds.Results: A total of 5801 records were found. After duplicates were removed and exclusion and inclusion criteria applied, 50 articles were included (n = 2615 participants). Their outcome measures were extracted and findings were synthesized. The majority of the reviewed papers covered the European continent (62%) and used global positioning systems (GPS) (64%). Measurement error of the tools used to obtain position data and running metrics was systematically overlooked among the studies. The main aims of studies were to examine differences across playing positions (20%), age groups (26%) and match halves (36%). Consistent findings pointed to the existence of positional role and age effects on match running output (using fixed running speed thresholds), but there was no clear consensus about reductions in activity over the course of match play. Congested schedules negatively affected players' running performance. While over 32% of all studies assessed the relationships between match running performance and physical capacity, biochemical markers and body composition, ~ 70% of these did not account for playing position.Conclusions: This review collated scientific evidence that can aid soccer conditioning professionals in understanding external match loads across youth categories. Coaches working with youth development programs should consider that data derived from a given population may not be relevant for other populations, since game rules, match format and configuration are essentially unstandardized among studies for age-matched players. Despite limited evidence, periodization training emphasizing technical-tactical content can improve match running performance. Occurrence of acute and residual impairments in the running performance of young soccer players is common. Prescription of postmatch recovery strategies, such as cold water immersion and spa treatment, can potentially help reduce these declines, although additional research is warranted. This review also highlighted areas requiring further investigation, such as the possible influence of environmental and contextual constraints and a more integrative approach combining tactical and technical data. [ABSTRACT FROM AUTHOR]

Background: Soccer is the most popular sport worldwide, with a long history and currently more than 500 million active participants, of whom 300 million are registered football club members. On the basis of scientific findings showing positive fitness and health effects of recreational soccer, FIFA (Fédération Internationale de Football Association) introduced the slogan 'Playing football for 45 min twice a week-best prevention of non-communicable diseases' in 2010. Objective: The objective of this paper was to perform a systematic review and meta-analysis of the literature to determine the effects of recreational soccer on maximal oxygen uptake ( $$ \dot{V}{\text{O}}_{2\;\hbox{max} } $$ ). Methods: Six electronic databases (MEDLINE, PubMed, SPORTDiscus, Web of Science, CINAHL and Google Scholar) were searched for original research articles. A manual search was performed to cover the areas of recreational soccer, recreational physical activity, recreational small-sided games and $$ \dot{V}{\text{O}}_{2\;\hbox{max} } $$ using the following key terms, either singly or in combination: recreational small-sided games, recreational football, recreational soccer, street football, street soccer, effect, maximal oxygen uptake, peak oxygen uptake, cardiorespiratory fitness, $$ \dot{V}{\text{O}}_{2\;\hbox{max} } $$ . The inclusion criteria were divided into four sections: type of study, type of participants, type of interventions and type of outcome measures. Probabilistic magnitude-based inferences for meta-analysed effects were based on standardised thresholds for small, moderate and large changes (0.2, 0.6 and 1.2, respectively) derived from between-subject standard deviations for baseline fitness. Results: Seventeen studies met the inclusion criteria and were included in the systematic review and meta-analysis. Mean differences showed that $$ \dot{V}{\text{O}}_{2\;\hbox{max} } $$ increased by 3.51 mL/kg/min (95 % CI 3.07-4.15) over a recreational soccer training programme in comparison with other training models. The meta-analysed effects of recreational soccer on $$ \dot{V}{\text{O}}_{2\;\hbox{max} } $$ compared with the controls of no exercise, continuous running and strength training were most likely largely beneficial [effect size (ES) = 1.46; 95 % confidence interval (CI) 0.91, 2.01; I = 88.35 %], most likely moderately beneficial (ES = 0.68; 95 % CI 0.06, 1.29; I = 69.13 %) and most likely moderately beneficial (ES = 1.08; 95 % CI −0.25, 2.42; I = 71.06 %), respectively. In men and women, the meta-analysed effect was most likely largely beneficial for men (ES = 1.22) and most likely moderately beneficial for women (ES = 0.96) compared with the controls. After 12 weeks of recreational soccer with an intensity of 78-84 % maximal heart rate (HR), healthy untrained men improved their $$ \dot{V}{\text{O}}_{2\;\hbox{max} } $$ by 8-13 %, while untrained elderly participants improved their $$ \dot{V}{\text{O}}_{2\;\hbox{max} } $$ by 15-18 %. Soccer training for 12-70 weeks in healthy women resulted in an improvement in $$ \dot{V}{\text{O}}_{2\;\hbox{max} } $$ of 5-16 %. Significant improvements in $$ \dot{V}{\text{O}}_{2\;\hbox{max} } $$ have been observed in patients with diabetes mellitus, hypertension and prostate cancer. Conclusion: Recreational soccer produces large improvements in $$ \dot{V}{\text{O}}_{2\;\hbox{max} } $$ compared to strength training and no exercise, regardless of the age, sex and health status of the participants. Furthermore, recreational soccer is better than continuous endurance running, albeit the additional effect is moderate. This kind of physical activity has great potential for enhancing aerobic fitness, and for preventing and treating non-communicable diseases, and is ideal for addressing lack of motivation, a key component in physical (in)activity. [ABSTRACT FROM AUTHOR]

Background: Protein supplements are frequently consumed by athletes and recreationally active adults to achieve greater gains in muscle mass and strength and improve physical performance. Objective: This review provides a systematic and comprehensive analysis of the literature that tested the hypothesis that protein supplements accelerate gains in muscle mass and strength resulting in improvements in aerobic and anaerobic power. Evidence statements were created based on an accepted strength of recommendation taxonomy. Data Sources: English language articles were searched through PubMed and Google Scholar using protein and supplements together with performance, exercise, strength, and muscle, alone or in combination as keywords. Additional articles were retrieved from reference lists found in these papers. Study Selection: Studies recruiting healthy adults between 18 and 50 years of age that evaluated the effects of protein supplements alone or in combination with carbohydrate on a performance metric (e.g., one repetition maximum or isometric or isokinetic muscle strength), metrics of body composition, or measures of aerobic or anaerobic power were included in this review. The literature search identified 32 articles which incorporated test metrics that dealt exclusively with changes in muscle mass and strength, 5 articles that implemented combined resistance and aerobic training or followed participants during their normal sport training programs, and 1 article that evaluated changes in muscle oxidative enzymes and maximal aerobic power. Study Appraisal and Synthesis Methods: All papers were read in detail, and examined for experimental design confounders such as dietary monitoring, history of physical training (i.e., trained and untrained), and the number of participants studied. Studies were also evaluated based on the intensity, frequency, and duration of training, the type and timing of protein supplementation, and the sensitivity of the test metrics. Results: For untrained individuals, consuming supplemental protein likely has no impact on lean mass and muscle strength during the initial weeks of resistance training. However, as the duration, frequency, and volume of resistance training increase, protein supplementation may promote muscle hypertrophy and enhance gains in muscle strength in both untrained and trained individuals. Evidence also suggests that protein supplementation may accelerate gains in both aerobic and anaerobic power. Limitations: To demonstrate measureable gains in strength and performance with exercise training and protein supplementation, many of the studies reviewed recruited untrained participants. Since skeletal muscle responses to exercise and protein supplementation differ between trained and untrained individuals, findings are not easily generalized for all consumers who may be considering the use of protein supplements. Conclusions: This review suggests that protein supplementation may enhance muscle mass and performance when the training stimulus is adequate (e.g., frequency, volume, duration), and dietary intake is consistent with recommendations for physically active individuals. [ABSTRACT FROM AUTHOR]