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Context: The Neurotracker CORE assessment is an 8-minute multiple object tracking (MOT) program used in sport science research and clinical rehabilitation as a perceptual-cognitive training tool; however, it has garnered interest for its potential use as an acute assessment of cognitive performance. Although some data exist regarding the learning effect of repeated exposures, it is often overlooked with investigators focusing primarily on the presence of transfer effects to other cognitive realms. As a result, exclusive data on the effect of repeated testing, or subsequent periods of no testing (ie, detraining) on test–retest reliability, and on MOT performance are sparse. Design: Repeated-measures/reliability. Methods: Twenty-three recreationally active men and women completed 15 training sessions consisting of 2 CORE assessments per session (30 assessments). Participants were randomized to either 1 or 2 weeks of detraining prior to completing 15 retraining sessions (30 assessments). Training and retraining periods were divided into 10 blocks (3 assessments/block) for analysis. MOT speed threshold (MOT-ST), consistency, fastest trial score success speed, lowest trial score miss speed, the number of perfect, near misses, and significant miss trials within each block were used to determine performance. Intraclass correlation coefficient, standard error of measurement, and minimal detectable change were used to determine reliability. Results: Significant improvements in MOT-ST and fastest trial score success speed were noted within training blocks 1 to 6 and 1 to 7, respectively (P <.05). MOT-ST and fastest trial score success speed demonstrated excellent test–retest reliability between blocks 8 and 9. There was no effect of detraining period on performance during retraining. Conclusions: Eighteen tests are necessary to overcome training effects and establish a reliable baseline when MOT-ST is used as the performance outcome. Detraining periods up to 2 weeks did not impact performance. The average of 3 discrete tests should be used when assessing MOT-ST performance. [ABSTRACT FROM AUTHOR]

Context: Adductor longus muscle strains are one of the most common injuries occurring in intermittent sports such as soccer. Objective: The purpose of this study was to know the effect of a specific rehabilitation and reconditioning program, which was previously validated, after adductor longus injury in professional soccer players. Methods: A specific rehabilitation and reconditioning program was applied to 11 injured male professional soccer players. Participants: Eleven male professional soccer players (age = 29.18 [4.45] y; height = 179.64 [4.97] cm; mass = 75.33 [3.84] kg). Interventions: In the first place, the days taken to return to full team training and to return to competition (RTP) was analyzed; second, the most important performance parameters were analyzed and compared in the preinjury match (PRE) and after the return to competition at 2 different points in time (RTP1–RTP2). Results: The return to full team training recorded was 11.91 (1.92) days and the RTP was 15.36 (3.04) days. Match performance parameters showed significant improvements after injury. Significant improvements were observed during RTP2, in the variables of high-speed running (P =.002), very high-speed running (P =.006), acceleration (>3 m/s2; P =.048), and high metabolic load distance (P =.009). Conclusion: The results allow us to conclude that this program was very effective, as it allowed the players to obtain similar and/or higher performance values in a reduced period of time after the injury. [ABSTRACT FROM AUTHOR]

Context: As blood flow restriction gains popularity across different populations (eg, young and older adults) and settings (eg, clinical and sports rehabilitation), the accuracy of blood flow restricted percentage becomes crucial. We aimed to compare manually measured arterial occlusion pressure (AOP) among young adults to understand whether lower limb composition affects the pressure required to achieve AOP. The results will shed light on the adequacy of published calculations used to estimate AOP in practical and research settings. Design: An observational cross-sectional study design was implemented to examine the relationship between lower limb composition, lower limb circumference, and measured AOP. Methods: Twenty-two participants (12 males, 26 [4] y, 1.74 [0.07] m, 73.2 [12.5] kg) underwent a whole-body Dual-energy X-ray Absorptiometry scan before AOP (in millimeters of mercury) and lower limb circumference (in centimeters) were determined. In a supine position, a 10-cm wide cuff was manually inflated on the dominant leg to the point where a pulse could no longer be detected by a Doppler ultrasound of the posterior tibial artery to determine AOP. Lower limb composition (fat, muscle, and bone mass [in grams]) was obtained from the Dual-energy X-ray Absorptiometry scan. Results: Lower limb muscle mass had a moderate negative relationship with AOP (r2 =.433, β = −0.004) and a moderate positive relationship with lower limb circumference (r2 =.497, β = 0.001). Lower limb circumference had the weakest relationship with AOP (r2 =.316, β = 0.050) of all measures. Conclusions: The reported relationships between lower limb muscle mass, lower limb circumference, and AOP suggest that as muscle mass increases, lower limb circumference also increases, yet AOP decreases. This implies that limb circumference should not be used as the primary measure for calculating AOP within the sampled population. We recommend individually measuring AOP when implementing blood flow restriction in all exercise modalities. [ABSTRACT FROM AUTHOR]

Context: Instrument-assisted soft tissue mobilization (IASTM) continues to increase in popularity and utilization among manual therapists. Despite its popularity, little is known about the consistency in peak or average forces that clinicians apply when performing IASTM treatments with a 2-handed grip. The purpose of this study was to examine intraclinician consistency in peak and average forces when applying a 2-handed IASTM grip. Design: Randomized crossover study conducted in a university biomechanics laboratory. Methods: Five (5) licensed athletic trainers with prior IASTM training used 5 different IASTM instruments to apply simulated treatment. Average peak forces (Fpeak) and average mean forces (Fmean) were collected via force plate for all 5 IASTM instruments with a skin simulant attached. Descriptive statistics, coefficients of variation (CVs), box and density plots, and Bland–Altman plots were assessed. Results: The clinicians' average Fpeak ranged from 3.0 N to 11.6 N and average Fmean from 1.9 N to 8.1 N. Fpeak CVs for all instruments ranged from 14% to 31%, and Fmean CVs ranged from 15% to 35%. Bland–Altman plots indicated that for both Fpeak and Fmean, 97% of the data points fell within the limits of agreement across instruments and clinicians. Mean differences across instruments ranged from 0.9 N (91.8 g) to 4.1 N (418.1 g) for Fpeak and from 1.0 N (102.0 g) to 2.8 N (285.5 g) for Fmean. Thus, CVs, box and density plots, and Bland–Altman plots supported general force application consistency. Conclusion: Trained IASTM clinicians produced consistent treatment application forces (ie, Fpeak and Fmean) within treatment sessions during 2-handed simulated application. [ABSTRACT FROM AUTHOR]

Context: The evaluation of quadriceps muscle inhibition with the interpolated twitch technique is usually performed by stimulating the femoral nerve (FN). However, there are some problems related to the use of this stimulation site, which may be partially overcome by delivering the stimulation over the motor point (MP). This study sought to compare MP to FN stimulation at different joint angles for the evaluation of quadriceps muscle inhibition, resting peak torque, and discomfort in healthy women. Design: Cross-sectional study. Methods: Sixteen healthy women (age: 28 [4] y; body mass: 60 [5] kg; height: 162 [5] cm) participated in this study. Supramaximal paired stimuli were delivered to the FN and to the rectus femoris MP before and during maximal voluntary contractions at different knee angles (15°, 30°, 45°, 60°, and 90° of knee flexion) to assess muscle inhibition and resting peak torque. Discomfort was also recorded for each stimulation site and knee angle. Results: Muscle inhibition was similar between the 2 stimulation sites (P >.05) and was higher at 45° than at 90° (P =.03). MP stimulation evoked lower resting peak torque at 30° (P =.004), 60° (P =.006), and 90° (P =.006) and higher discomfort at 30° (P =.008) and 90° (P =.027) compared to FN stimulation. Conclusions: Despite lower resting peak torque and higher discomfort at some angles, MP stimulation provided similar muscle inhibition to FN stimulation at all knee angles and is therefore a valid method to evaluate quadriceps muscle inhibition in healthy women. MP stimulation can be used as an alternative to FN stimulation for the evaluation of quadriceps muscle inhibition with no added discomfort at the angles where muscle inhibition is the highest. [ABSTRACT FROM AUTHOR]

Objective: To culturally adapt and validate the Italian version of the Shoulder Instability—Return to Sport after Injury (SI-RSI-I) scale. Methods: The SI-RSI-I was developed by adapting the Anterior Cruciate Ligament—Return to Sport Index—Italian version and replacing the term "knee" with "shoulder." Subsequently, it underwent validation following COSMIN recommendations. The study involved athletic participants who experienced SI. They completed the SI-RSI-I together with other measurement instruments: Western Ontario Shoulder Instability Index, Kerlan-Jobe Orthopedic Clinic Score, EuroQol-5D-5L, and Numeric Pain Rating Scale. The following psychometric properties were investigated: structural validity, internal consistency, test–retest reliability, measurement error, and construct validity. Results: The study included 101 participants (age mean [SD] 28.5 [7.4] y; 83 males, 18 females). The SI-RSI-I showed a single-factor structure, excellent internal consistency (α =.935), and excellent test–retest reliability (ICC =.926; 95% CI,.853–.964). The standard error of measurement was 6.1 points, and the minimal detectable change was 17.0 points. Furthermore, SI-RSI-I demonstrated moderate to strong correlations with all reference scales, confirming 8 out of 9 (88.0%) hypotheses, thus establishing satisfactory construct validity. Conclusion: The SI-RSI-I has demonstrated robust internal consistency, reliability, validity, and feasibility as a valuable scale for assessing psychological readiness to return to sport in Italian athletes with SI. [ABSTRACT FROM AUTHOR]

Context: Psychological concerns, such as athlete burnout and diminished well-being, have become a more recognized problem among collegiate student-athletes due to substantial demands. The purpose of this study was to determine if (1) an association exists between athlete burnout and well-being in female collegiate student-athletes and (2) social support has a main or buffering-effect on well-being and athlete burnout. Design: Cross-sectional. Methods: 174 National Collegiate Athletic Association Division I female collegiate student-athletes were recruited from a single institution to participate. A web-based survey was distributed via Qualtrics during the middle of an academic semester. The following scales were utilized to evaluate social support, athlete burnout, and well-being: Perceived Available Support in Sport Questionnaire, Athlete Burnout Questionnaire, and Warwick Edinburgh Metal Well-Being Scale. Results: Correlation analyses presented a significant negative, moderate correlation (r = −.58, P <.001) between athlete burnout and well-being as well as between social support and athlete burnout (r = −.526, P <.001). A moderate, positive correlation was identified between social support and well-being (r =.604, P <.001). Social support was a significant predictor for reduced sense of accomplishment (F1,172 = 68.32, P <.001), physical and emotional exhaustion (F1,172 = 22.00, P <.001), sport devaluation (F1,172 = 56.51, P <.001), and well-being (F1,172 = 115.3, P <.001). Conclusion: Findings provide new information on theory-based considerations for reducing athlete burnout and improving well-being in female collegiate student-athletes. [ABSTRACT FROM AUTHOR]

Context: The Y-Balance Test Lower Quarter (YBT-LQ) is a widely utilized tool for evaluating dynamic postural control, requiring a combination of mobility and strength. This study aimed to investigate the combined relationship between isometric thigh muscle strength and joint kinematics on YBT-LQ performance. Design: Cross-sectional laboratory study. Methods: Isometric quadriceps and hamstrings strength were measured before the YBT-LQ in 39 healthy participants (27 females and 12 males). The test was performed under 3-dimensional markerless motion capture, where joint kinematics were extracted from the maximum reach position from each direction. Three multivariable linear regression models were then used to determine the strongest combination of predictors for YBT-LQ performance. Results: Greater hamstrings strength and increased knee flexion, ankle dorsiflexion, and trunk ipsilateral-flexion joint angles explained 56.8% (P <.001) of the variance in anterior reach. Hip flexion, knee flexion, and ankle dorsiflexion angles were the strongest predictors for posteromedial reach distance, explaining 73.0% of the variance (P <.001). Last, 43.3% (P <.001) of the variance in posterolateral reach distance was predicted by hamstring strength and knee-flexion angle. Conclusions: These results emphasize the importance of hamstring strength in YBT-LQ performance across different reach directions. Additionally, the kinematics illustrate a potential movement strategy for maximizing reach distance on the YBT-LQ in healthy individuals. Clinicians can utilize this information to guide interventions aimed at improving dynamic postural control, particularly by focusing on increasing hamstring strength and testing for impairments in specific movement patterns. [ABSTRACT FROM AUTHOR]

Context: The quadriceps femoris is consistently ranked among the muscles most prone to sustain strain injuries in sports involving kicking and sprinting actions. Given the documented preventive effect of Nordic hamstring curl programs against hamstring strain injuries, incorporating exercises that induce eccentric overload on the quadriceps could potentially help mitigate strain injuries within this muscle group. The Reverse Nordic Curl (RNC) has emerged as a viable field-based exercise for eccentrically working the quadriceps. This study aimed to compare quadriceps muscle eccentric activation during the RNC with 3 bodyweight squat-based exercises: single-leg squat (SLS), Bulgarian squat, and forward lunge. Design: Cross-sectional study. Methods: Twenty-three healthy volunteers (15 men) were monitored for rectus femoris, vastus lateralis, and vastus medialis electromyographic signal, as well as knee range of motion, while performing 10 repetitions of each exercise. Electromyography data acquired during eccentric phases were normalized by maximum voluntary isometric contraction of the knee extensors. The exercises were compared based on the electromyography and knee range of motion values. Results: RNC generated a similar rectus femoris and vastus medialis eccentric activation compared with the squat-based exercises (P >.05 for all), and a lower vastus lateralis activation than SLS (P <.001). Among the bodyweight squat-based exercises, SLS generated greater eccentric activation than forward lunge and Bulgarian squat for the 3 muscles (P <.05 for all). RNC was performed with lower knee-flexion range of motion than bodyweight squat-based exercises (P <.001). Conclusions: RNC did not produce superior eccentric quadriceps activation compared to bodyweight squat-based exercises, even proving to be less demanding for the vastus lateralis compared to the SLS. These findings may assist practitioners in selecting exercises to elicit quadriceps eccentric stimulus, with a focus on preventing strain injuries. [ABSTRACT FROM AUTHOR]

Context: The Upper Limb Functional Index (ULFI) is a popular tool with valid psychometric properties to assess upper limb function in patients with musculoskeletal conditions. The aim of the study was to cross-culturally adapt and validate the German version of the ULFI. Design: Cross-cultural validation. Methods: A 2-stage cross-cultural adaptation of the ULFI was performed according to international guidelines through consecutive forward and backward translations. Psychometric properties of internal consistency, test–retest reliability, criterion, face and content validity, and factor structure were determined from the included German participants suffering from upper limb conditions (n = 100), who fulfilled the following inclusion criteria: (1) older than 18 years old, (2) German as native language, and (3) medical diagnosis of musculoskeletal upper limb condition. Participants completed the ULFI; Disabilities of the Arm, Shoulder, and Hand; EuroQol Health Questionnaire 5 Dimensions; and Short Form-12 questionnaires. Results: The ULFI-G showed good internal consistency (α =.88); excellent test–retest reliability (intraclass correlation coefficient2:1 =.98); directly strong correlation with Disabilities of the Arm, Shoulder, and Hand (r =.84); fair correlation with Disabilities of the Arm, Shoulder, and Hand-sport (r =.54); inversely fair correlation with EuroQol Health Questionnaire 5 Dimensions (r = −.62); and Short Form 12's physical health domain (r = −.7). A single-factor structure was revealed. Conclusions: The ULFI-G showed adequate psychometric properties and proved to be a valid tool for upper limb functional assessment in German population. [ABSTRACT FROM AUTHOR]

Context: Several clinical tests are available to assess static postural stability in individuals with chronic ankle instability (CAI); however, it is unclear which test should be used. Objective: To determine which noninstrumented clinical tests should be used to detect static postural stability deficits in individuals with CAI. Evidence Acquisition: We searched 4 databases from their inception to February 2023, and included studies comparing static postural stability in individuals with CAI and healthy controls using noninstrumented assessments. Two reviewers independently extracted study characteristics, participant information, static postural stability assessment methods, and results. We calculated the pooled standardized mean difference (SMD) and 95% confidence interval using a random effects meta-analysis and assessed the certainty of the evidence. Evidence Synthesis: Fourteen cross-sectional studies (293 participants with CAI and 284 healthy controls) were included. The meta-analysis showed no significant differences between the CAI and healthy groups in the double-leg stance condition of the Balance Error Scoring System (BESS) (SMD, −0.03; low-certainty evidence). Significant group differences were found in the BESS single-leg stance (SLS) on firm and foam surfaces (SLS firm: SMD, 0.47, very low-certainty evidence; SLS foam: SMD, 0.80, very low-certainty evidence), the tandem stance (TS) on firm and foam surfaces (TS firm: SMD, 0.39, low-certainty evidence; TS foam: SMD, 0.76, low-certainty evidence), and the total BESS in the foam conditions (SMD, 1.12, very low certainty evidence). Significant differences were also found between the CAI and healthy groups in the foot-lift (SMD, 1.24; very low certainty evidence) and time-in-balance tests (SMD, −0.94; very low certainty evidence). Conclusions: Due to the large magnitude of the differences, the SLS foam, TS foam, and the total BESS in the foam conditions, as well as the foot-lift test or time-in-balance test, may be the most appropriate to clinically identify static postural stability impairment in individuals with CAI. [ABSTRACT FROM AUTHOR]

Beta-alanine is a nonessential amino acid that is commonly used to improve exercise performance. It could influence the buffering of hydrogen ions produced during intense exercise and delay fatigue, providing a substrate for increased synthesis of intramuscular carnosine. This systematic review evaluates the effects of beta-alanine supplementation on maximal intensity exercise in trained, young, male individuals. Six databases were searched on August 10, 2023, to identify randomized, double-blinded, placebo-controlled trials investigating the effect of chronic beta-alanine supplementation in trained male individuals with an age range of 18–40 years. Studies evaluating exercise performance through maximal or supramaximal intensity efforts falling within the 0.5–10 min duration were included. A total of 18 individual studies were analyzed, employing 18 exercise test protocols and 15 outcome measures in 331 participants. A significant (p =.01) result was observed with an overall effect size of 0.39 (95% confidence interval [CI] [0.09, 0.69]), in favor of beta-alanine supplementation versus placebo. Results indicate significant effects at 4 weeks of supplementation, effect size 0.34 (95% CI [0.02, 0.67], p =.04); 4–10 min of maximal effort, effect size 0.55 (95% CI [0.07, 1.04], p =.03); and a high beta-alanine dosage of 5.6–6.4 g per day, effect size 0.35 (95% CI [0.09, 0.62], p =.009). The results provide insights into which exercise modality will benefit the most, and which dosage protocols and durations stand to provide the greatest ergogenic effects. This may be used to inform further research, and professional or recreational training design, and optimization of supplementation strategies. [ABSTRACT FROM AUTHOR]

This study aimed to determine energy availability (EA) and within-day energy balance (WDEB) in female soccer players during preseason and also explored eating disorder risk and athlete food choice. We hypothesized commonly used indicators of low energy availability (LEA) risk would correlate with measured EA and WDEB variables, and that food choice determinants would differ according to EA. Eleven National Premier League female soccer players participated in this observational cross-sectional study over 3 weeks. Assessment of resting metabolic rate and physique traits, including bone mineral density, was conducted during Weeks 1 or 3. During Week 2, dietary intake, energy expenditure, and continuous monitor-derived glucose were measured for 5 days. EA was calculated daily and WDEB calculated hourly with deficits/surpluses carried continuously. Questionnaires were administered throughout the 3 weeks, including the Athlete Food Choice Questionnaire, the Eating Disorders Screen for Athletes, and the Low Energy Availability in Females Questionnaire. Resting metabolic rate ratio, bone mineral density, Low Energy Availability in Females Questionnaire, and Eating Disorders Screen for Athletes scores were used as indicators of LEA risk. EA averaged 30.7 ± 7.5 kcals·kg fat-free mass−1·day−1. Approximately one-third (36%) of athletes were at risk of an eating disorder, while approximately half (45%) were identified at risk of the female athlete triad via Low Energy Availability in Females Questionnaire, compared with approximately one-third (36%) of athletes identified with EA < 30 kcal·kg fat-free mass−1·day−1. No athlete achieved EA >45 kcal·kg fat-free mass−1·day−1, and no indicator of LEA risk was associated with calculated EA or WDEB. However, overnight glycemic variability was positively correlated with measured EA (r =.722, p =.012). [ABSTRACT FROM AUTHOR]

Objective: Micronutrient status, specifically vitamin D and iron, represent modifiable factors for optimizing military readiness. The primary purpose of this investigation was to determine associations between micronutrient deficiency (i.e., iron status and 25-hydroxy-vitamin D [25(OH)D]) and operationally relevant outcomes (i.e., skeletal health, musculoskeletal injury) at baseline and post-10 weeks of arduous military training. Methods: A total of 227 (177 men, 50 women) Marine Officer Candidates School (OCS) candidates who completed OCS training with complete data sets were included in this analysis. Vitamin D and iron status indicators were collected at two timepoints, pre (baseline) and post OCS. Musculoskeletal outcomes at the mid- and proximal tibial diaphysis were assessed via peripheral quantitative computed tomography. Results: Micronutrient status declined following OCS training in men and women and was associated with musculoskeletal outcomes including greater bone strength (strength strain index) at the mid-diaphysis site in those with optimal status (M = 38.26 mm3, SE = 15.59) versus those without (M = −8.03 mm3, SE = 17.27). In women (p =.037), endosteal circumference was greater in the deficient group (M = 53.26 mm, SE = 1.19) compared with the optimal group (M = 49.47 mm, SE = 1.31) at the proximal diaphysis. In men, greater baseline hepcidin concentrations were associated with an increased likelihood of suffering musculoskeletal injury during training. Conclusions: Vitamin D and iron status declined over the course of training, suggesting impaired micronutrient status. Differences in musculoskeletal outcomes by micronutrient group suggests optimal vitamin D and ferritin concentrations may exert beneficial effects on bone fatigability and fracture reduction during military training. [ABSTRACT FROM AUTHOR]

Background: Several studies have revealed the positive healthy impacts of branched-chain fatty acids (BCFAs). However, most of these studies evaluated the serum BCFAs in humans, or treatment with exogenous BCFAs in animal or in-vitro models and the health impacts of dietary BCFAs have not yet been studied. Due to positive effects of BCFAs in sport, in the current study, we aimed to investigate the association between dietary BCFAs and metabolic and inflammatory parameters among elite and subelite soccer players. Methods: A cross-sectional study was carried out among 335 elite and subelite soccer players (196 male), aged between 20 and 45 years old. Soccer players were enrolled from 32 teams under the directive of The Chinese Football Association. Demographic, anthropometric, and dietary assessments were performed and laboratory measurement including serum lipids, glycemic markers, and high-sensitivity C-reactive protein was measured. Results: Those with the highest dietary BCFAs consumption had higher appetite (p =.009). Also, high consumption of dietary BCFAs was associated with lower diastolic blood pressure (odds ratio: 0.958; confidence interval: 0.918–0.999; p =.046) and low high-sensitivity C-reactive protein concentrations in the third tertile of dietary BCFAs (odds ratio: 0.431; confidence interval: 0.300–0.618; p <.001). No other association between biochemical variables and dietary BCFAs was found. Conclusion: As shown in the current study, higher dietary BCFAs consumption was associated with lower diastolic blood pressure and inflammation. Due to very limited number of studies, further studies are needed to have a better perspective of these associations and their underlying mechanisms. [ABSTRACT FROM AUTHOR]

This study investigated the effect of oral and topical sodium bicarbonate (SB) on soccer-specific performance during simulated soccer exercise. In a block randomized, double-blind, crossover design, 10 collegiate male soccer players (stature: 181.7 ± 3.2 cm, body mass: 81.7 ± 10.5 kg) performed soccer-specific performance tests (countermovement jumps, Illinois agility, 8 × 25 m repeated sprints) throughout a 90-min soccer-specific aerobic field test (SAFT90) following 0.3 g/kg body mass SB in capsules (SB-ORAL), 0.9036 g/kg body mass PR Lotion (SB-LOTION), or placebo capsules and lotion (PLA). Soccer-specific performance tests were conducted pre-SAFT90, during half-time and post-SAFT90. Blood samples were analyzed for acid–base balance (pH; bicarbonate, HCO 3 − ) and strong ions (sodium, Na+; potassium, K+). Average sprint times were quicker for SB-ORAL than PLA during half-time (3.7%; p =.049; g =.57) and post-SAFT90 (4.9%; p =.041; g =.66). SB-ORAL increased pH and HCO 3 − prewarm-up and during half-time (p <.05), and lowered K+ during half-time (p =.035) compared with PLA. SB-LOTION increased pH (p =.019) and lowered K+ (p =.012) during half-time compared with PLA. SB-LOTION increased Na+ postexercise compared with PLA (p =.008). Repeated sprint times during simulated soccer exercise improved for SB-ORAL, which might have been mechanistically underpinned by elevated blood buffering capacity and greater regulation of strong ion concentration. Consuming SB in capsules is a more effective strategy than topical SB application for improving blood buffering capacity and repeated sprint performance throughout competitive soccer matches. [ABSTRACT FROM AUTHOR]

Objectives: Dietary strategies to improve arachidonic acid:eicosapentaenoic acid (AA:EPA) ratios are of interest due to potential reductions in inflammation and oxidative stress following exercise. The aim of this study was to investigate the impact of a novel dietary intervention, that is, the ingestion of 30 g of dark chocolate, on blood lipid profiles and gut microbiota composition in elite male soccer players. Methods: Professional male soccer players were randomly assigned to the experimental group (DC) provided with 30 g of dark chocolate or to the control group (WC), provided with 30 g of white chocolate, for 30 days. Before and after intervention, blood, fecal sample, and anthropometry data were collected. For each outcome, two-way repeated-measure analysis of variance was used to identify differences between baseline and endpoint (Week 4), considering treatment (dark chocolate, white chocolate) as intersubjects' factors. Metagenomic analysis was performed following the general guidelines, which relies on the bioBakery computational environment. Results: DC group showed increased plasma polyphenols (from 154.7 ± 18.6 μg gallic acid equivalents/ml to 185.11 ± 57.6 μg gallic acid equivalents/ml, Δ pre vs. post = +30.41 ± 21.50) and significant improvements in lipid profiles: total cholesterol (Δ −32.47 ± 17.18 mg/dl DC vs. Δ −2.84 ± 6.25 mg/dl WC, Time × Treatment interaction p <.001), triglycerides (Δ −6.32 ± 4.96 mg/dl DC vs. Δ −0.42 ± 6.47 mg/dl WC, Time × Treatment interaction p <.001), low-density lipoprotein (Δ −18.42 ± 17.13 mg/dl vs. Δ −2.05 ± 5.19 mg/dl WC, Time × Treatment interaction p <.001), AA/EPA ratio (Δ −5.26 ± 2.35; −54.1% DC vs. Δ −0.47 ± 0.73, −6.41% WC, Time × Treatment interaction p <.001) compared with WC group. In addition, 4 weeks of intervention showed a significant increase in high-density lipoprotein concentration in DC group (Δ + 3.26 ± 4.49 mg/dl DC vs. Δ −0.79 ± 5.12 mg/dl WC). Microbial communities in the DC group maintained a slightly higher microbial stability over time (exhibiting lower within-subject community dissimilarity). Conclusion: Ingesting 30 g of dark chocolate over 4 weeks positively improved AA:EPA ratio and maintained gut microbial stability. Dark chocolate ingestion represents an effective nutritional strategy to improve blood lipid profiles in professional soccer players. What Are the Findings? Ingesting 30 g of dark chocolate for 4 weeks positively influences blood lipid AA: EPA ratio while maintaining gut microbial stability. What This Study Adds? Dietary intake of specific foods such as dark chocolate represents an alternative strategy to support the health and recovery of elite soccer players. WhatImpact Might This Have on Clinical Practice in the Future? From a clinical and translational perspective, dark chocolate ingestion positively modulates favorable blood lipid profiles and polyunsaturated fatty acid metabolism while maintaining gut microbial stability. Dark chocolate ingestion may be considered as an effective nutritional strategy in elite sport environments during periods of high-intensity training and congested competitions. Further research is required to determine functional outcomes associated with the observed improvements in blood lipid profiles. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this investigation was to assess alterations of pulmonary oxygen uptake ( V ˙ O 2 ) and muscle deoxygenation on-kinetics during heavy-intensity cycling in youth cyclists over a period of 15 months. Methods: Eleven cyclists (initial age, 14.3 [1.6] y; peak V ˙ O 2 , 62.2 [4.5] mL·min−1·kg−1) visited the laboratory twice on 3 occasions within 15 months. Participants performed an incremental ramp exercise test and a constant workrate test within the heavy-intensity domain during the first visit and second visit, respectively. Subsequently, parameter estimates of the V ˙ O 2 and muscle deoxygenation on-kinetics were determined with mono-exponential models. Results: The V ˙ O 2 phase II time constant decreased from occasion 1 (34 [4] s) to occasion 2 (30 [4] s, P =.005) and 3 (28 [4] s, P =.010). However, no significant alteration was observed between occasions 2 and 3 (P =.565). The V ˙ O 2 slow component amplitude either expressed in absolute values (ie, L·min−1) or relative to end exercise V ˙ O 2 (ie, %) showed no significant changes throughout the study (P =.972 and.996). Furthermore, the muscle deoxygenation on-kinetic mean response time showed no significant changes throughout the study (18 [8], 18 [3], and 16 [5] s for occasions 1, 2, and 3, respectively; P =.279). Conclusion: These results indicate proportional enhancements of local muscle oxygen distribution and utilization, which both contributed to the speeding of the V ˙ O 2 on-kinetics herein. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to investigate the effect of agility ladder training combined with plyometric or multidirection speed drills, on performance in young female volleyball players. Methods: Seventy-six young female volleyball players were randomly distributed into 3 maturity-matched groups: (1) the agility ladder + plyometric drills group, (2) the agility ladder + multidirection speed drills group, and (3) the control group. Both experimental groups followed a 6-week training program, twice weekly, in addition to the regular volleyball training sessions, while the control group participated only in the regular volleyball training sessions. Assessments pretraining and posttraining included countermovement jump, 20-m sprint, and agility T test. Results: Both experimental groups improved T-test performance (P <.005) but only agility ladder + multidirection speed drills group outperformed the control group (P <.05). Conclusions: Agility ladder training programs combined with either plyometric or speed drills can improve change of direction performance in young female volleyball players but only the combination of agility ladder with multidirection speed drills is more effective than volleyball training per se. The small effectiveness of these protocols may be attributed to the short training period, or to the fact that training elements were combined in a single session. This hypothesis remains to be further investigated. [ABSTRACT FROM AUTHOR]

Purpose: To describe serum irisin and fibroblast growth factor-21 (FGF-21) concentrations in healthy female adolescents with different training activity patterns and their associations with bone mineral properties and metabolic markers. Methods: A total of 62 adolescent girls aged 14–18 years were recruited: 22 rhythmic gymnasts, 20 swimmers, and 20 untrained controls. Bone mineral characteristics by dual-energy X-ray absorptiometry, daily energy intake by dietary recall, serum irisin, FGF-21, undercarboxylated osteocalcin, and C-terminal telopeptide of type I collagen were measured in all girls. Results: Whole body and lumbar spine areal bone mineral density and lumbar spine bone mineral content were higher in the rhythmic gymnasts group compared with swimmers and untrained controls groups (P <.05). Serum irisin, FGF-21, undercarboxylated osteocalcin, and C-terminal telopeptide of type I collagen levels were not significantly different between the groups. In the rhythmic gymnasts group, serum FGF-21 concentration was positively correlated with lumbar spine areal bone mineral density independently of confounding factors (r =.51; P =.027). Conclusions: Serum irisin and FGF-21 levels were not different between adolescent eumenorrheic girls with different training activity patterns. FGF-21 was positively associated with lumbar spine areal bone mineral density, which predominantly consists of trabecular bone in adolescent rhythmic gymnasts. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to explore the interday reliability of mechanical variables obtained from the horizontal and vertical force–velocity (FV) profiles in adolescent female basketball players. If found to be reliable, the associations between FV parameters (theoretical maximal force, velocity, and power), squat jump (SJ) height, 30-m sprint, and change of direction (COD) times were evaluated. Methods: After familiarization, SJ against incremental loads, 30-m sprint, and 505-COD tests were obtained twice in 36 adolescent female basketball players (age = 15.4 [1.2] y). Results: Reliability for vertical FV parameters was unacceptable, whereas 505-COD times and FV horizontal parameters (except for theoretical maximal power) showed a moderate to high reliability. 505-COD time was correlated with FV horizontal parameters (range: r = −.821, −.451), and a large association was observed with both SJ height (r = −.678, −.600) and 30-m sprint time (r =.813,.858). Conclusions: Due to low levels of strength, our athletes were not adequately prepared to obtain a reliable vertical FV profile. Practitioners can expect acceptable reliability of the horizontal FV profile. Given the association between COD performance and SJ height and 30-m sprint time, we encouraged practitioners with limited equipment at their disposal to use COD and/or 30-m sprint tests. [ABSTRACT FROM AUTHOR]

This study critically examines the suitability of using a single drop height to assess the reaction strength index in trained and active participants, a key component of athletic performance. Using a cross-sectional design, 377 trained (n = 163) and active (n = 214) participants aged 14–18 years performing drop jumps from 4 different heights (24, 32, 40, and 48 cm) were studied. The primary aim was to explore the individual differences in reaction strength index at these heights and to assess whether a single height can reliably represent stretch-shortening cycle capabilities. While the repeated measures analysis of variance did not reveal any significant differences, the Bland–Altmann analysis revealed significant individual discrepancies between the performance of the drop heights, resulting in a mean absolute error of 32.1 and a mean absolute percentage error of 20.6%. These results strongly suggest that a single drop height is not sufficient to determine performance in the stretch-shortening cycle. This has important practical implications as it can lead to underestimates of performance trends. The study advocates the inclusion of a range of drop heights in routine testing to accurately measure reactive power and thus improve the effectiveness of individualized training programs for young athletes/active youth. [ABSTRACT FROM AUTHOR]

Purpose: To compute reference centiles for 5- and 30-m sprint times relative to chronological and skeletal age in youth soccer players. Subsequently, to compare individual's sprint performance scores derived from the chronological and skeletal age reference centiles. Methods: Sprint times were collected for a sample of male U11 to U19 soccer players (n = 1745 data points). Skeletal age data were available for a subsample (n = 776 data points). Reference centiles were fitted using generalized additive models for location, scale, and shape. Individual z scores relative to chronological and skeletal age reference centiles were computed and compared for each maturity group (late, on-time, early, and very early) using standardized mean differences (SMD). Results: Reference centiles for chronological age increased more rapidly between 10.5 and 15.5 years, while reference centiles for skeletal age increased more rapidly between 13.0 and 16.5 years. Differences in chronological and skeletal z scores for very early (SMD: −0.73 to −0.43) and late (SMD: 0.58 to 1.29) maturing players were small to large, while differences for early (SMD: −0.30 to −0.19) and on-time (SMD: 0.16 to 0.28) were trivial to small. Conclusion: Reference centiles provide a valuable tool to assist the evaluation of sprint performance in relation to chronological and skeletal age for talent identification purposes in youth soccer players. [ABSTRACT FROM AUTHOR]

Recruiting neurodiverse talent has increasingly featured on the organizational diversity agenda, yet recruitment practices geared toward locating and attracting neurodivergent candidates remain understudied. While research and practice have shown that employee referral is one of the channels through which a significant part of new talent is recruited, little is known about employees' willingness to refer qualified social contacts who are neurodivergent. We address this limitation by investigating employees' willingness to refer highly qualified candidates on the autism spectrum and some conditions under which they are more or less likely to refer such candidates. We explore these aspects in a study of working individuals, using a mixed‐method approach. The quantitative analysis shows that disclosure of an autism condition to potential referrers might pose some advantage, in that it increases the likelihood of being referred, but this advantage accrues only to male candidates. Furthermore, cues that hint at the social dimension of the "ideal worker," commonly used in job recruitment materials, are the strongest deterrent for referrers. The qualitative analysis of the reasons behind decisions to refer sheds light on some mechanisms that might explain these findings. [ABSTRACT FROM AUTHOR]

Drawing on gender role and gender queuing theories, we employ a multi‐stage process model to investigate demand‐ and supply‐side drivers of gender promotion gaps and to explore variations in these gaps across different business units within an organization. Analyzing 9 years of personnel records from a multiunit European bank, we find that the gender promotion gap is influenced by both supply‐side and demand‐side factors. Specifically, women are less likely than men to express a motivation to change to a new job or move to a different unit within the bank. Those who do express such motivation are as likely as men to be reassigned to new roles, but their moves are less likely to constitute promotions than are men's moves. Furthermore, gender promotion gaps vary significantly within the organization itself. Business units with the most significant gaps are in regions that have fewer available organizational positions to move into, diminishing women's motivation to seek such moves, and have jobs with numerous incumbents, decreasing women's chances to get a new job or secure a promotion upon doing so. This study extends gender role theory by creating a unified theoretical model that incorporates both employee and employer gender role perceptions as drivers of promotions. It contributes to gender queuing theory by demonstrating the theory's relevance to promotion outcomes. [ABSTRACT FROM AUTHOR]

Work passion—a motive that contains affective and cognitive components—is highly desirable and has positive consequences for individuals and organizations. We propose work passion as the missing piece that can explain unique variance in job satisfaction above and beyond the established predictor of dispositional affect. Taking a motivational approach based on the Dualistic Model of Passion and self‐determination theory, we tested how two types of work passion (harmonious and obsessive) and two types of dispositional affect (positive and negative) predicted overall job satisfaction and nine job satisfaction facets (satisfaction with pay, promotion, supervision, fringe benefits, contingent rewards, operating conditions, coworkers, the nature of work, and communication). In a two‐wave study of working adults, structural equation modeling and regression‐based relative weights analysis showed that harmonious passion predicted the largest proportion of variance in job satisfaction overall and in all nine of its facets. Together, our findings highlight the importance of harmonious passion and the utility of a motivational theoretical perspective on job satisfaction for HR scholars and practitioners. [ABSTRACT FROM AUTHOR]

Organizations must excel at what they do well while also learning new ways of operating to achieve long‐term success. Work teams may thus find themselves pursuing contradictory objectives to support the organization's strategy. We investigated teams' goal orientation (in)congruence and its impact on task meaningfulness and, ultimately, performance, hypothesizing the potential pitfalls of teams simultaneously pursuing both learning‐ and performance‐goal orientations. Three‐wave, multisource data were collected from 109 teams at a large North American mortgage company. In a polynomial regression and response surface analytical framework, team task meaningfulness—and subsequent team performance—was enhanced when teams had greater divergence between their learning‐ and performance‐goal orientations but suffered when both goal orientations were more aligned. Our investigation thus revealed the potential pitfalls of teams simultaneously pursuing both learning‐ and performance‐goal orientations. We discuss the theoretical contributions of the team goal orientation incongruence effect substantiated in this study, as well as implications for practice and future research. [ABSTRACT FROM AUTHOR]

Employees increasingly conduct work outside of traditional work hours via information communication technologies (ICTs). There is a need to understand how after‐hours ICT use relates to well‐being, given that such connectivity has become unavoidable. We implement an episodic, event‐contingent design to evaluate the association between different ICT media (i.e., e‐mail, phone call, chat app, short message service) and the within‐person outcomes of psychological detachment as partially mediated by task productivity. A daily diary survey was collected over three consecutive workdays to capture after‐hours ICT use. Daily surveys were completed by 498 individuals, with a total of 1494 episodes being captured of after‐hours work ICT engagement. Our results indicate that while engagement with any form of ICT after hours reduces psychological detachment, email and chat apps are associated with the lowest levels of psychological detachment. Moreover, whereas the use of asynchronous ICT has positive main effects on episode‐related task productivity, the use of synchronous ICT (e.g., phone) only enhances episode‐related task productivity when there are high organizational expectations for employees' responsiveness after hours. [ABSTRACT FROM AUTHOR]

While the compressed workweek (CWW) has gained traction in recent years, its impact on firms' financial performance is not well understood. This study addresses this gap in the literature by examining the effect of the CWW on shareholder value. Drawing on social exchange theory and its norm of reciprocity, we introduce a conceptual model on the main effect of the CWW on shareholder value, and the moderating roles of the anticipated type and degree of employee reciprocation. To test the model's predictions, we exploit the announcement of Belgium's mandatory adoption of a CWW in February 2022 as the setting for a policy event study analysis. We find positive average stock price reactions of Belgian listed firms to the CWW's announcement, consistent with investors expecting the CWW to result in favorable employee reciprocation. Stock price reactions are more positive for firms with a lower ex ante employee productivity, suggesting employees are predicted to reciprocate with higher efforts. Stock price reactions are also more positive for firms with a higher reliance on knowledge workers, consistent with these employees deriving a greater utility from flexible working arrangements. Robustness tests, including a placebo analysis and an event study of international firms with Belgian subsidiaries, corroborate our results. Our study offers several theoretical contributions and has practical implications for HR managers and policymakers. [ABSTRACT FROM AUTHOR]

Purpose: To describe and compare the race characteristics, demands, and durability profile of a male and a female Grand Tour winner. Methods: Overall and stage-type-specific (ie, time trials, flat, semimountainous, and mountain) demands and race characteristics during 2 Grand Tours were determined and compared between the female and male cyclists. In addition, relative power output distribution and pacing, percentage of functional threshold power (FTP), and changes in maximal mean power outputs (MMPs) with increasing levels of kilojoules burned were determined. Results: Although many differences were found between course and absolute racing demands between the male (FTP: 413 W; critical power: 417 W) and female (FTP: 297 W; critical power: 297 W) cyclists, similar power distributions and pacing strategies were found if data were expressed relatively. However, the female cyclist rode a higher percentage of her FTP during the first 2 quarters of flat stages (14.7%–15.1%) and the last quarter of mountain stages (9.8%) than the male cyclist. Decrements in MMPs were only observed after burning 30 kJ·kg−1 in the female and 45 kJ·kg−1 in the male Grand Tour winner. Conclusions: Both the male and female Grand Tour winners produced very high 20- to 60-minute MMPs, whereas decrements in MMPs were only observed after having burned 75% (female) and 80% (male) of total kilojoules burned during a stage. These are the latest and lowest in MMPs reported in the scientific literature and highlight the importance of durability in combination with excellent climbing and time-trial skills, which are needed to be able to win a Grand Tour. [ABSTRACT FROM AUTHOR]

Purpose: The traditional understanding of how coaches plan for sporting performance is rooted in the assumption that coaches create periodized plans underpinned by physiological principles, thereby providing scientific credibility to their work. In contrast, there remains a paucity of literature exploring how coaches understand or think about their planning practices. The purpose of this study was to generate new knowledge regarding what information coaches actually consider within their planning processes and how they actually approach the task of planning. Method: Using rigorous, in-depth interviews, this study examined athletics coaches' understandings of their everyday planning practices, in an attempt to contribute to narrowing the gap between academic research and real-world application. Twenty-eight highly experienced, high-performance track-and-field coaches based in England (female, n = 1; male, n = 27) were recruited. The coaches were from the throwing disciplines (n = 10) and endurance running (n = 18). Coaches were interviewed about their planning process, using a maximum of 3 semistructured interviews per coach, spaced across a full athletics season. In total, this generated 68 hours of data. Results: The analysis demonstrated that, while the participant coaches utilized the principles of periodization, their planning activities were not limited to this issue. The findings highlighted how the coaches conceptualized successful athletic performance in a holistic way; that is, planning is multifaceted in nature. Conclusion: This study presents a holistic picture of the complexity of coaches' planning, detailing the considerable time and attention given to planning for athletes' psychological, personal, and social development, to enhance athlete performance and development. [ABSTRACT FROM AUTHOR]

Purpose: To examine the reproducibility and sensitivity of a self-paced field running test (SFT) in monitoring positive and negative changes in endurance performance. Methods: A total of 27 (11 women) recreational runners participated in a 6-week training intervention. The intervention was divided into a 3-week baseline period, a 2-week overload period, and a 1-week recovery period. An incremental treadmill test was performed before the baseline period and a 3000-m running test before and after all periods (T1–T4). In addition, the participants performed once a week an SFT (SFT1–6), which consisted of submaximal (6 + 6 + 3-min test at perceived exertion of 9/20, 13/20, and 17/20) and maximal sections (6 × 3-min intervals at maximum sustainable effort). The associations between the incremental treadmill test and the SFT1 performance were examined with the Pearson correlation, and the intraclass correlation was analyzed for the parameters of SFT1 to SFT3 sessions during the baseline period. The repeated-measures correlation was calculated for the 3000-m speed at T1 to T4 and the corresponding speeds at SFT. Results: Significant associations (r =.68–.93; P <.001) were found between the speeds of the SFT and the peak and lactate threshold speeds of the incremental treadmill test. Intraclass correlations varied between.77 and.96, being the highest for the average speed of 6 × 3-minute intervals. Repeated-measures correlation was significant (P <.05) for the 9/20 (r =.24), 13/20 (r =.24), and 6 × 3-minute intervals (r =.29). Conclusions: The SFT seemed a reproducible method to estimate endurance performance in recreational runners. The sensitivity to track short-term and small-magnitude changes in performance seems more limited and might require more standardized conditions. [ABSTRACT FROM AUTHOR]

Purpose: To study whether, during typical-level running, non-rear-foot strikers (non-RFS) or rear-foot strikers (RFS) presented a similar or different extent of neuromuscular fatigue after a prolonged graded run. Methods: Sixteen experienced male trail runners (8 non-RFS and 8 RFS) performed a 2.5-hour treadmill graded running exercise. Before and after exercise, neuromuscular tests were performed to assess neuromuscular fatigue of the plantar flexors. Biomechanical gait parameters were acquired with an instrumented treadmill, and electromyographic activity of the lower-limb muscles was collected as an index of muscle activation. Results: There were no significant time × foot strike interactions for neuromuscular (all P ≥.742), muscle activation (all P ≥.157), or biomechanical (all P ≥.096) variables. Conclusions: A dominant level running foot-strike pattern did not directly affect the extent of neuromuscular fatigue during a prolonged graded run. This suggests that no ideal running foot-strike pattern exists to minimize neuromuscular fatigue during prolonged-duration races wherein cumulative uphill and downhill segments are high, such as in trail running. [ABSTRACT FROM AUTHOR]

Purpose: We investigated the effects of manipulating running velocity and hypoxic exposure on vastus lateralis muscle oxygenation levels during treadmill running. Methods: Eleven trained male distance runners performed 7 randomized runs at different velocities (8, 10, 12, 14, 16, 18, and 20 km·h−1), each lasting 45 seconds on an instrumented treadmill in normoxia (fraction of inspired oxygen [FiO2] = 20.9%), moderate hypoxia (FiO2 = 16.1%), high hypoxia (FiO2 = 14.1%), and severe hypoxia (FiO2 = 13.0%). Continuous assessment of Tissue Saturation Index (TSI) in the vastus lateralis muscle was conducted using near-infrared spectroscopy. Subsequently, changes in TSI (ΔTSI) data over the final 20 seconds of each run were compared between velocities and conditions. Results: There was a significant velocity × condition interaction for ΔTSI% (P <.001, η p 2 =.19), with a smaller ΔTSI% decline in normoxia compared with high hypoxia and severe hypoxia at 8 km·h−1 (g = 1.30 and 1.91, respectively), 10 km·h−1 (g = 0.75 and 1.43, respectively), and 12 km·h−1 (g = 1.47 and 1.95, respectively) (pooled values for all conditions: P <.037). The ΔTSI% decline increased with each subsequent velocity increment from 8 km·h−1 (−9.2% [3.7%]) to 20 km·h−1 (−22.5% [4.1%]) irrespective of hypoxia severity (pooled values for all conditions: P <.048). Conclusions: Running at slower velocities in conjunction with high and severe hypoxia reduces vastus lateralis muscle oxygenation levels. Muscle ΔTSI% proves to be a sensitive indicator, underscoring the potential use of near-infrared spectroscopy as a reference index of internal load during treadmill runs. [ABSTRACT FROM AUTHOR]

Objective: Passive stiffness, a biomechanical parameter, has a potential influence on running economy, thus playing a pivotal role in performance. This study aimed to quantify passive stiffness of the Achilles tendon and gastrocnemius muscle using myotonometry throughout an incremental running protocol. Methods: Twenty-one male participants underwent a multistage incremental test (Bordeaux test) on a treadmill until exhaustion. Passive stiffness of the gastrocnemius muscle and Achilles tendon was measured using a MyotonPRO device. Measurements were taken before, during, and after the incremental test. Results: Our findings indicated that passive stiffness of the medial gastrocnemius decreased at rest between prerun and postrun assessments (−20.12 N·m−1, P =.012). Furthermore, during the test, stiffness increased at low intensity (at 50% of maximal aerobic speed: +104.8 N·m−1, P =.042), returning to baseline values as intensity increased. Conclusions: Throughout an incremental running protocol, both Achilles tendon and gastrocnemius muscle stiffness initially increased and then decreased with escalating percentages of maximal aerobic speed. A deeper understanding of stiffness in running can inform more effective recommendations for runners' strengthening and training. [ABSTRACT FROM AUTHOR]

Purpose: The current study aimed to determine the effect of a synthetic-grass sport surface on core body temperature, skin temperature, heart rate, thermal sensation, thermal comfort, and rating of perceived exertion (RPE) during intermittent exercise in hot conditions. Methods: Using a randomized crossover design, 13 trained/developmental team-sport athletes completed two 50-minute standardized intermittent running protocols on a synthetic and a natural-grass surface, on separate days (control-condition air temperature 32.6 °C [1.3 °C], relative humidity 43.2% [5.3%]). Results: Final skin temperature was significantly higher on synthetic compared with natural grass at the calf (40.1 °C [2.5 °C] vs 33.4 °C [0.6 °C]; P <.001), shoulder (36.6 °C [1.7 °C] vs 33.7 °C [0.7 °C]; P <.001), and chest (33.2 °C [1.1 °C] vs 31.8 °C [1.2 °C]; P =.02). Thermal sensation (median: 2.3; interquartile range [0.5] vs 2.2 [0.5], P =.03) and sweat rate (1.5 [0.4] L·h−1 vs 1.2 [0.3] L·h−1; P =.02) were also significantly higher on synthetic grass. While final core body temperature was significantly higher on the natural than synthetic grass (38.4 °C [0.3 °C] vs 38.2 °C [0.4 °C]), there were no significant differences in delta core temperature, as well as heart rate, thermal comfort, or RPE. Conclusions: Higher skin temperatures, thermal sensation, and sweat rates suggest that exercising on synthetic grass in hot conditions may increase some markers of heat strain during exercise. However, delta core body temperature, heart rate, thermal comfort, and RPE remained unaffected. [ABSTRACT FROM AUTHOR]

Purpose: Continuous glucose monitors (CGMs) are becoming increasingly popular among endurance athletes despite unconfirmed accuracy. We assessed the concurrent validity of the FreeStyle Libre 2 worn on 2 different sites at rest, during steady-state running, and postprandial. Methods: Thirteen nondiabetic, well-trained recreational runners (age = 40 [8] y, maximal aerobic oxygen consumption = 46.1 [6.4] mL·kg–1·min–1) wore a CGM on the upper arm and chest while treadmill running for 30, 60, and 90 minutes at intensities corresponding to 50%, 60%, and 70% of maximal aerobic oxygen consumption, respectively. Glucose was measured by manually scanning CGMs and obtaining a finger-prick capillary blood glucose sample. Mean absolute relative difference, time in range, and continuous glucose Clarke error grid analysis were used to compare paired CGM and blood glucose readings. Results: Across all intensities of steady-state running, we found a mean absolute relative difference of 13.8 (10.9) for the arm and 11.4 (9.0) for the chest. The coefficient of variation exceeded 70%. Approximately 47% of arm and 50% of chest paired glucose measurements had an absolute difference ≤10%. Continuous glucose Clarke error grid analysis indicated 99.8% (arm) and 99.6% (chest) CGM data fell in clinically acceptable zones A and B. Time-in-range analysis showed reduced accuracy at lower glucose levels. However, CGMs accurately detected trends in mean glucose readings over time. Conclusions: CGMs are not valid for point glucose monitoring but appear to be valid for monitoring glucose trends during steady-state exercise. Accuracy is similar for arm and chest. Further research is needed to determine whether CGMs can detect important events such as hypoglycemia during exercise. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to compare running economy across habituated and nonhabituated advanced footwear technology (AFT) in trained long-distance runners. Methods: A total of 16 participants completed up to six 5-minute trials in 1 to 3 pairs of their own habituated shoes and 3 different and standardized AFTs at individual marathon pace. We measured oxygen uptake and carbon dioxide production and expressed running economy as oxygen uptake (in milliliters oxygen per kilogram per minute), oxygen cost of transport (oxygen per kilogram per minute), energetic cost (in watts per kilogram), and energetic cost of transport (in joules per kilogram per kilometer). We used linear mixed-effect models to evaluate differences. Relative shoe weight and shoe mileage (distance worn during running) were covariates. Results: Forty-eight standardized and 29 individual AFT conditions were measured (mileage 117.0 [128.8] km, range 0–522 km; 25 habituated 135.7 [129.2] km, range 20–522 km; 4 nonhabituated 0 [0] km, range 0–0 km). Rating of perceived exertion, blood [La], and respiratory exchange ratio ranged from 9 to 15, 1.11 to 4.54 mmol/L, and 0.76 to 1.01. There was no effect for habituation on energetic cost of transport (thabituation = −.232, P =.409, b = −0.006; 95% CI, −0.058 to 0.046) or other running economy metrics. Neither shoe weight nor shoe mileage had an effect. Conclusions: Our results suggest that habituation to AFTs does not result in greater benefits in the use of AFTs. This means that implementation in training may not be needed, even if we cannot rule out any other possible benefits of habituation at this stage, such as adaptation of the musculoskeletal system. [ABSTRACT FROM AUTHOR]

Objectives: Assess the effect of water dousing on heat strain and performance during self- and fixed-paced exercise in the heat. Design: Crossover, block-randomized controlled trial. Methods: Thirteen trained runners completed a 10-km time trial (TT) and 60-minute fixed-pace run (60% velocity of V ˙ O 2 max) in a 30.4 °C, 47.4% relative humidity environment using either water dousing (DOUSE) or no dousing (CON). Results: Ten-kilometer TT performance was faster in DOUSE compared to CON (44:11 [40:48, 47:34] vs 44:38 [41:21, 47:56] min:s; P =.033). Change in core temperature (Tc) was not different between groups during the TT (+0.02 [−0.04, 0.07] °C in DOUSE; P =.853) or fixed-pace run (+0.02 [−0.15, 0.18] °C; P =.848). Change in mean skin temperature was lower in DOUSE during the TT (−1.80 [−2.15, −1.46] °C; P <.001) and fixed-pace run (−1.38 [−1.81, −0.96] °C; P <.001). Heart rate was lower for DOUSE during the fixed-pace run (−3.5 [−6.8, −0.2] beats/min; P =.041) but not during the TT (−0.2 [−2.5, 2.1] beats/min; P =.853). Thermal sensation was lower for DOUSE during the TT (−49.3 [−72.1, −26.1] mm; P <.001) and fixed-pace run (−44.7 [−59.7, −29.6] mm; P <.001). Rating of perceived exertion was not different between groups for the TT (−0.2 [−0.7, 0.3]; P =.390) or fixed-pace run (−0.2 [−0.8, 0.4]; P =.480). Sweat rate was lower for DOUSE for the TT (−0.37 [−0.53, −0.22] L/h; P <.001) and fixed-pace run (−0.37 [−0.48, −0.26] L/h; P <.001). Conclusion: Water dousing improves 10-km TT performance in the heat but does not affect Tc. The positive change in thermal perception (via lower skin temperature) during the TT likely drives this benefit. [ABSTRACT FROM AUTHOR]

Purpose: This study compared the physiological profiles and energy-system contributions of trained football players engaged in regular-passing and third-man-passing small-sided games (SSGs) that included 4 versus 4 and a goalkeeper. Methods: Ten male trained football players participated in this crossover study. All participants were randomly assigned to either regular-passing SSG or third-man-passing SSG (4 vs 4 with a goalkeeper, 35-m × 17-m pitch size, and 6-min match duration). During these SSGs, physiological parameters including peak and mean heart rate, oxygen uptake ( V ˙ O 2 peak and V ˙ O 2 mean), metabolic equivalents in V ˙ O 2 peak and V ˙ O 2 mean , and blood lactate concentrations (peak La− and delta La− [Δ La−]), were measured. Energy contributions (oxidative [WOxi], glycolytic [WGly], and phosphagen [WPCr] systems) and Global Positioning System (GPS) variables (total distance, total acceleration counts, mean speed, and maximum speed) were also analyzed. Results: No significant differences in physiological parameters and GPS variables were found between regular- and third-man-passing SSGs. WOxi in kilojoules and percentages was significantly higher during both SSGs than WPCr and WGly (P <.0001, respectively). WPCr and WPCr + WGly values during third-man-passing SSGs were significantly higher than those during regular-passing SSGs (P <.05). Additionally, low to moderate positive correlations were observed between WOxi, WGly in kilojoules, V ˙ O 2 peak , V ˙ O 2 mean , peak La−, Δ La−, total acceleration counts, and mean speed (r =.39–.64). Conclusions: Third-man-passing SSGs may be useful for increasing anaerobic capacity. More third-man-passing SSG sessions in preparation for football games may support high metabolic power and repeated powerful anaerobic performances in trained football players. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to investigate the effects of acute ischemic preconditioning (IPC) on tennis skill and physical exercise performance, as well as to explore whether 7-day repeated IPC (RIPC) accelerated fatigue recovery after a simulated tennis match. Methods: Twenty-nine male tennis-specific current students were randomly allocated into 1 of 2 groups: SHAM (n = 14, 3 × 5 min at 20 mm Hg) and IPC (n = 15, 3 × 5 min at 220 mm Hg). Participants in both groups engaged in acute IPC and RIPC interventions. After the first acute IPC intervention, assessments were conducted to evaluate tennis-specific skills and overall physical exercise capacity. Following completion of chronic RIPC interventions, all participants competed in a simulated tennis match specifically designed to induce fatigue. To evaluate recovery from this induced fatigue, physical exercise capacity tests were conducted at 24 and 48 hours postmatch, allowing for an assessment of the participants' recovery capabilities over time. Results: After the first acute intervention, notable differences were observed between the IPC and SHAM groups in their performance on the repeated-sprint ability test. Specifically, the total times recorded were significantly shorter in the IPC group compared with the SHAM group (IPC: 109.05 [2.70] vs SHAM: 114.57 [7.45] s, P =.012), and this trend was also reflected in their best times (IPC: 4.20 [0.18] s vs SHAM: 4.39 [0.30] s, P =.042), indicating an immediate benefit of the IPC intervention on sprint performance. After a 7-day RIPC intervention, significant changes were noted in the SHAM group's performance metrics postmatch. There was an increase (P <.001) in fatigue index from 22% (8%) to 30% (9%) during repeated-sprint ability test and a decrease in serve speed from 120.2 (17.5) to 106.7 (13.0) km/h (P =.002) and knee peek torque from 196.0 (49.0) to 162.7 (39) N (extension, 60°/s, P <.001) in the SHAM group 24 hours postmatch, relative to the IPC group. Moreover, compared with the SHAM group, the IPC group showed a lower rate of perceived exertion during the match (P <.001) and a decrease in visual analog scale score (P =.026) 24 hours postmatch, suggesting enhanced recovery and reduced perception of pain relative to the SHAM group. Conclusion: IPC could serve as a strategy to generate an ergogenic effect and recovery during training and competition. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the training and development process of a multiple-Grand-Slam finalist. Methods: A mixed-methods case-study design was used to capture the quantitative and qualitative aspects related to the training and successful development process. We used a 3-step data-collection process and pragmatic analyses of (1) training history based on logs, plans, and questionnaires; (2) in-depth semistructured interviews with the player's head coach/father, physical coach, and team administrator/mother; and (3) systematic quality assurance through negotiation among researchers and all key informants, including the player. Results: The player's exceptional performance level was achieved by a progressive, nonlinear increase in annual training load during childhood and early youth, stabilizing at 800 sessions and 1250 to 1300 hours per year at the age of 19. The annual tennis-specific training plateaued at ∼750 hours from the age of 15, and 60 to 80 matches were played in most of the analyzed years. Point-play accounted for approximately 50% of the total amount of specific tennis training, clearly ahead of ground strokes (∼30%), serve/return (∼15%), and smash/volley (∼5%). Physical-conditioning hours increased 5-fold from 12 to 19 years, before stabilizing at ∼500 hours at senior age. Key success factors included the athlete's multidimensional sports talent, discipline, and inner drive; a highly dedicated father and tennis-enthusiastic family; and strong support from a complementary and interdisciplinary performance team. Conclusion: This study provides novel information regarding the training and development process for a world-leading tennis player, providing a point of departure for the development of future talents. [ABSTRACT FROM AUTHOR]

Purpose: To compare power output and pacing between maximal 1500- and 2000-m on-water rowing performances. Methods: Twenty-six (female n = 4, male n = 22) international rowers, across 6 boat classes, completed maximal 1500- and 2000-m on-water races, separated by 24 to 48 hours. Crew combinations and seat orders remained consistent between races. Peach PowerLine instrumentation measured power output and stroke rate. Differences in completion time, mean power output (MPO), percentage prognostic velocity (PPV; percentage of world record velocity in each boat class), stroke rate, and pacing variance were assessed using linear mixed modeling. Results: Compared with 2000-m, completion times were 90.4 (6.1) seconds shorter over 1500 m (−24.7% [0.7%]). Both MPO (P =.255, η p 2 =.06) and PPV (P =.340, η p 2 =.18) were not different between distances. Broadly, crews adopted a reverse-J-shaped pacing across both distances, demonstrating a reduced variance over 1500 m (P =.035, η p 2 =.62). Percentage change in MPO from 2000 to 1500 m demonstrated a strong negative association with pacing variance over 1500 m (R2 =.74, P =.027). Conclusions: International rowing crews did not increase MPO or PPV when racing maximally over 1500 m compared to 2000 m. Comparable strategies were adopted over both distances, with less variance in pacing observed over 1500 m. The crews that demonstrated greater increases in MPO over the shorter race employed a flatter pacing strategy. To improve 1500-m on-water performance, rowers may need to adopt a more even pacing approach. [ABSTRACT FROM AUTHOR]

Purpose: To assess the effect of whole-body cryotherapy (WBC) on postmatch recovery in basketball. Methods: Using a crossover design, 17 youth male players (age 16.2 [1.2] y, stature 190.5 [9.4] cm, body mass 79.2 [9.6] kg, experience 9.9 [3.9] y) completed 2 simulated matches, followed by WBC (4 min, −75 to − 85 °C) or a placebo intervention (CON). Countermovement-jump height, change-of-direction performance, 10- and 20-m sprint times, heart-rate variability (log-transformed squared root of the mean sum of the squared differences between R-R intervals [Ln-rMSSD]), muscle soreness, and perceived recovery (Perceived Recovery Status Scale [PRS]) were recorded at prematch, postmatch, postrecovery, and 24 hours postmatch. Additionally, Ln-rMSSD was recorded upon awakening on match day and the following morning. Results: Compared with CON, higher PRS values were reported in WBC at prematch and postrecovery (P ≤.026), while no significant between-interventions differences were found for any other measure (P >.05). Regarding the effect of time, our findings revealed that 20-m sprint times, Ln-rMSSD, and PRS deteriorated in both interventions from prematch to postmatch (ie, acute changes, P ≤.045), while muscle soreness worsened in WBC only (P ≤.003). Conversely, countermovement-jump height, change-of-direction, and 10-m sprint performance were unaffected by match play in the acute phase (P >.05), while none of the investigated measures showed impairments at 24 hours postmatch, compared with prematch (P >.05). Conclusions: Overall, these findings suggest that WBC was mostly ineffective for improving postexercise recovery in the investigated sample, with benefits observed for perceived recovery being potentially influenced by the participants' status at baseline (ie, higher prematch PRS scores in WBC compared with CON). [ABSTRACT FROM AUTHOR]

Background: The benefits of oral caffeine intake to enhance several aspects of physical performance, such as aerobic endurance, strength, power, and muscle endurance performance, are well supported. However, how the physical performance benefits of caffeine supplementation are translated into better specific actions in intermittent sports during real or simulated competition has been the topic of fewer investigations, and their results need to be appropriately reviewed and meta-analyzed. Objective: The aim of the study was to investigate the effects of acute caffeine intake on specific actions in intermittent sports involving decision making and high-intensity efforts (eg, team, racket, and combat sports) during real or simulated competitions. Methods: All studies included had blinded and crossover experimental designs, and we conducted a risk-of-bias analysis. In total, we included 24 studies. A meta-analysis was performed using the random-effects model to calculate the standardized mean difference (SMD) estimated by Hedges g and 95% CIs. Results: Caffeine ingestion increased high-intensity sport-specific actions during competition, such as the number of sprints (SMD: 0.48; 95% CI, 0.23–0.74), body impacts (SMD: 0.28; 95% CI, 0.08–0.49), accelerations (SMD: 0.35; 95% CI, 0.06–0.63), decelerations (SMD: 0.63; 95% CI, 0.12–1.14), and high-intensity offensive efforts (SMD: 0.36; 95% CI, 0.11–0.61). Additionally, caffeine ingestion induced a higher positive or success rate of actions during real or simulated competition (SMD: 0.44; 95% CI, 0.19–0.69). Conclusion: The current meta-analysis provides evidence of caffeine supplementation in increasing high-intensity efforts and the success rate of sport-specific actions during real or simulated competition. [ABSTRACT FROM AUTHOR]

This study explored the effect of different dual-task (DT) training programs on DT interference in adults with intellectual disability. Center-of-pressure (CoP) mean velocity in single-task (ST) and cognitive-DT conditions and the Timed Up-and-Go Test (TUGT) during ST, cognitive-DT, and motor-DT conditions were assessed before and after intervention in a cognitive–motor training group, a motor–motor training group, and a control group. Before training, CoP mean velocity and TUGT time increased (p <.001) in DT compared with the ST condition. After training, the CoP mean velocity values remained unchanged (p =.07) in DT compared with the ST condition among the cognitive–motor training group. Furthermore, compared with the ST condition, no increase (p = 1) was reported in the TUGT time during the cognitive-DT condition for the cognitive–motor training group and during the motor-DT for the motor–motor training group (p =.12). The effect of DT training on DT interference depends on the training modality. [ABSTRACT FROM AUTHOR]

Maximum running speed is a performance determinant in para-athletics and cerebral palsy football. Sixty international para-athletes with brain impairments completed five activity-limitation tests (standing broad jump, four bounds for distance, split jumps, 10-m speed skip, and running in place) and two criterion tests (40-m sprint and modified agility test). The same three tests (standing broad jump, four bounds for distance, and 10-m speed skip) that correlated with running performance in nondisabled runners (.67 < r < −.82; p <.05; 75% of variance) also correlated in para-athletes with brain impairments (.41 < r < −.62; p <.01; 55% of variance). Standing broad jump, four bounds for distance, split jumps, and running in place also correlated with change-of-direction speed (.43 < r < −.63; p <.01; 58% of variance). Results indicate that methods of classification for para-athletics with nondisabled runners are also valid with para-athletes with brain impairments, and new sport-specific relationships were found for assessing the performance of rapid and short sprints toward different directions, specific of a team para-sport like cerebral palsy football. [ABSTRACT FROM AUTHOR]

The adolescent population with Down syndrome (DS) appears to show higher levels of body fat and lower levels of cardiorespiratory fitness or muscle strength than their peers without disabilities. There is a need to create physical activity programs to improve these data. The aim of this research was to determine the effects of a 16-week swimming program, strength program, and combined program (swimming and strength training) on body composition and health-related physical fitness on adolescents with DS and to assess whether there are differences in the results of the different training programs. Forty-five adolescents (17 female and 28 male; average age 15.5 [1.53] years) with DS were recruited and randomized to three groups (swim [n = 15], strength [n = 15], and combined [n = 15]). Results showed that the swim group had significant improvements in all health-related physical fitness variables and there was an improvement in some body-composition variables (p <.05). The strength and combined groups obtained minor improvements in the variables analyzed. In summary, a 16-week swim program consisting of three sessions of 60 min is able to improve levels of body composition and health-related physical fitness in adolescents with DS. The swim training program seems to be more effective in improving body composition and health-related physical fitness than the strength or combined program. These findings could be useful in different special-education centers due to the predisposition shown by the population with DS to this sport modality. [ABSTRACT FROM AUTHOR]

This study examined the effects of a combined virtual-reality- and gym-based physical activity (PA) program on PA levels, motor skills, and social skills of children with a developmental disability (DD). Twenty-five children with DD were randomly assigned to experimental and control groups. The intervention was conducted for 60 min, two times a week, for 12 weeks. Pre- and postintervention assessments encompassing PA levels measured via Gravity Estimator of Normal Everyday Activity, motor skills evaluated using the Test of Gross Motor Development-Third Edition, and social skills gauged via the Social Skills Rating System-Parent were conducted. Additionally, a follow-up assessment was administered to the experimental group 12 weeks postintervention. The findings unequivocally demonstrate that the combined virtual-reality- and gym-based PA program yielded significant enhancements in PA levels, motor skills, and social skills among children with DD in the experimental group. Notably, these improvements were sustained 12 weeks after the intervention. These findings may help professionals develop and implement better PA programs for children with DD. [ABSTRACT FROM AUTHOR]

The journey of Brazilian female Paralympians transcends mere statistical increases in women's participation. Behind the modest athlete growth lies the reality of women who are doubly marginalized by the intersection of gender and disability in an arena tailored for able-bodied men. Our study aimed to catalyze critical discourses surrounding the historical trajectory of Paralympic women's sports. Through a comprehensive documentary analysis based on the Brazilian Paralympic Committee's official documents from 1976 to 2021, we sought to shed light on this complex scenario. Numerically, Brazil's representation comprised 229 women who, predominantly, had physical impairments and engaged in individual sports. In addition to a sporting legacy deeply entrenched in physical rehabilitation with limited opportunities for team-based sports, we observed negative influences stemming from ableist and sexist narratives. A thorough investigation into Paralympic milestones revealed a multitude of social barriers and highlighted the significant impact of societal changes in reshaping athletic opportunities and challenging traditional stereotypes. [ABSTRACT FROM AUTHOR]