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This study examined the frequency of the most demanding scenarios (MDS) during official soccer matches using rolling averages over 1, 5, and 10 min. Forty-two Under-19 players from different positions (central defenders, full-backs, central midfielders, wide midfielders, offensive midfielders, and forwards) were monitored across 27 matches using GPS to track distance covered, high-speed running, sprint distance, accelerations, and decelerations. Intensity thresholds were established based on percentiles (0–25, 25–50, 50–75, 75–100, and ≥100). The main findings suggest that: (i) Peak Demands occur in less than 1% of all time windows and variables for all positions; (ii) Most efforts occur below peak demands, with around 95% for high-speed running and sprint distance, and 85% for accelerations, decelerations, and total distance; (iii) Significant differences in intensity distributions were found between positions, particularly at medium-low and high intensities. Regarding training prescription, relying solely on MDS may be limited, highlighting the need to supplement MDS with other metrics for a comprehensive understanding of match demands. This approach ensures better-informed training programs for soccer players. Highlights: The occurrence of peak demand events during soccer matches is infrequent. Therefore, understanding the frequency of efforts below the intensity threshold of the most demanding passages for each playing position and across various analysed variables and periods is of utmost importance. MDS might not be enough for effective soccer training planning. Complementing with additional metrics like GPS, tactical analysis, physiological data and psychological factors is essential for a comprehensive understanding of the game's demands and tailored training programmes. [ABSTRACT FROM AUTHOR]

This study aimed to assess acute and residual changes in sprint-related hamstring injury (HSI) risk factors after a football (soccer) match, focusing on recovery within the commonly observed 72-h timeframe between elite football matches. We used a multifactorial approach within a football context, incorporating optical and ultrastructural microscopic analysis of BFlh (biceps femoris long head) muscle fibres, along with an examination of BFlh fibre composition. Changes in sprint performance-related factors and HSI modifiable risk factors were examined until 3 days after the match (MD +3) in 20 football players. BFlh biopsy specimens were obtained before and at MD +3 in 10 players. The findings indicated that at MD +3, sprint-related performance and HSI risk factors had not fully recovered, with notable increases in localized BFlh fibre disruptions. Interestingly, match load (both external and internal) did not correlate with changes in sprint performance or HSI risk factors nor with BFlh fibre disruption. Furthermore, our study revealed a balanced distribution of ATPase-based fibre types in BFlh, with type-II fibres associated with sprint performance. Overall, the results suggest that a 72-h recovery period may not be adequate for hamstring muscles in terms of both HSI risk factors and BFlh fibre structure following a football match. [ABSTRACT FROM AUTHOR]

The objective of this study was to test the vectorelectrocardiographic T-wave characteristics for their associations with oxygen consumption (VO2) and physical performance during a maximal cardiopulmonary exercise test (CPET) in highly trained cross-country skiers. Male highly trained cross-country skiers (n = 30) performed the maximal CPET on the bicycle ergospirometric "Oxycon Pro" system with simultaneous oxygen consumption (VO2) and electrocardiogram recording. The measurements were done at rest; the stage preceding anaerobic threshold (preAnT); peak load; and recovery. The anaerobic threshold was estimated by respiratory exchange ratio. Physical performance was estimated by maximal oxygen consumption (VO2max/kg). VECG characteristics were calculated using Kors transformation procedure. During the test, the magnitudes of T-vector, Tx and Ty components decreased until preAnT, then stayed relatively stable until peak load, and reversed during recovery. In univariate linear regression analysis, T-vector amplitude and Tx, Ty and Tz magnitudes were associated with VO2/kg during the test (p < 0.010). The baseline T-vector characteristics were not associated with physical performance. At the preAnT stage, Tx and T-vector amplitude were associated with VO2max/kg (RC 12.70, 95% CI 0.68–24.73, p = 0.039 and RC 10.64, 95% CI 1.62–19.67, p = 0.023, respectively). [ABSTRACT FROM AUTHOR]

A person-centred approach was used to examine whether children with various actual and perceived motor competence (AMC and PMC) profiles differ in (enjoyment of) physical fitness (PF). The strength of the relationship between AMC and PMC was also assessed through aligned assessment tools. A sample of 287 7–11-year-old children (47.40% boys, Mage = 8.92 ±.78 years) was assessed on AMC with the KörperkoordinationsTest für Kinder (KTK3), and on PF with six validated fitness tests. Animated videos fully aligned with the AMC- and PF-tests were used to assess children's PMC and enjoyment of PF, respectively. Cluster analyses identified one convergent (i.e. high AMC-high PMC) and three partially convergent AMC-PMC profiles (i.e. low AMC-high PMC). Furthermore, children with relatively high AMC (i.e. high-average profile) reported higher PF (F = 30.99, p <.001), while children with relatively high PMC (i.e. average-high profile) reported higher enjoyment of PF (F = 9.02, p <.001). The correlation between AMC and PMC was significant but weak (r =.16). Overall, it seems important to invest in both children's AMC and PMC as they may support a higher (enjoyment of) PF, potentially leading to higher PA-levels. Highlights: When it comes to physical fitness, actual motor competence rather than perceived motor competence seemed to play the biggest role. As extra high perceived motor competence did not add additional benefits in terms of physical fitness, there might have been a ceiling effect of perceived motor competence. When looking at enjoyment of physical fitness, perceived motor competence seemed to be a more important factor than actual motor competence. However, profile analyses revealed that a relatively high perceived motor competence score may not fully compensate the loss of enjoyment in physical fitness when children's actual motor competence is relatively low. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the effect of weighted vest on-field small-sided games (SSG) soccer training, during the in-season period, on body composition and soccer-specific performances, in young, trained soccer players. A counterbalance study design was adopted, in which the fourteen well-trained players (age: 19.1 ± 0.5 yrs, body mass: 70.3 ± 5.3 kg, body height: 180.3 ± 3.0 cm, body fat: 9.2 ± 4.1%) performed both the Interventional (Vest) and Control (Con) training routines (6 weeks/season; 5 training sessions/week; 1 match/week), in different occasions (winter/spring period). Con group followed a regular weekly training plan. When the Con group performed their intense training sessions, Vest group performed only the on-field SSGs training wearing a vest (12.5% of athletes' body mass). All the evaluations were performed one week before and after each training period. Statistical analyses include repeated ANOVA and T-test (p < 0.05). Significant increases in sprinting, jumping, change of direction (COD), aerobic and anaerobic performances were observed only after Vest intervention (−4.7 ± 2.2% to 11.2 ± 4.2%; p < 0.05). Significant changes were observed only after Vest training, compared to Cont (p < 0.05). These results suggest that using a weighted vest, during the in-season, onfield SSG training two times/week induces greater increases in young soccer players' sprinting, jumping, COD, aerobic and anaerobic performances. [ABSTRACT FROM AUTHOR]

Interval-training is widely implemented among populations with obesity to decrease metabolic-disorders; however, high-intensity-interval-training (HIIT) has rarely been studied in severely obese adolescent girls. Therefore, the aim of this study was to compare the effects of 8 weeks of (HIIT) or moderate-intensity interval-training (MIIT), on cardiometabolic risk factors and hormonal-ratios in severely-obese-girls. For this aim, 35 female-adolescents (14.4 ± 1.4 years) were assigned randomly into HIIT (n = 12) and MIIT (n = 12), groups and a control group (CG, n = 11). Both training groups significantly improved (p < 0.05): the body-mass, body-mass-index (BMIp95), body-fat (BF%), waist-circumference (WC), mean-arterial-pressure (MAP), with a slight increase in the HIIT group. However, HIIT induced greater improvements on the maximal oxygen uptake (VO2MAX) and the speed related (24.7 and 11.8%) compared to MIIT. Higher improvements occurred in HIIT group related to leptin and adiponectin concentrations and the A/L ratio at (p < 0.001). In conclusion, the findings indicate that both HIIT and MIIT can positively influence body composition and cardio-respiratory fitness. Given the significant correlation noted between the A/L ratio, BMIp95, BF%, and MAP post-HIIT, this training modality may be considered a more advantageous approach over MIIT for mitigating cardio-metabolic issues in severely obese adolescent girls. [ABSTRACT FROM AUTHOR]

Research assessing the effects of mouthpieces on an individual's aerobic, anaerobic, or muscular performance have attributed cited improvements to the participant's ability to jaw clench. Jaw clenching research finds positive outcomes with the task of jaw clenching with targeted muscle groups in a controlled laboratory setting. Thus, the study's goal was to determine if the addition of a mouthpiece would positively affect performance outcomes in a field-based whole-body muscle movement. Fourteen participants (8=F and 6=M) NCAA softball and baseball athletes completed 5 maximal bat swings with and without a mouthpiece in 4 conditions: no jaw clenching (NC), mouthpiece and jaw clenching (MP+C), mouthpiece only (MP), and jaw clenching only (C). Significant differences occurred in conditions, with the highest velocity noted in the combined condition of MP+C (71.9 mph) as compared to NC (67.9 mph), MP (68.6 mph), and C (70.9 mph). A repeated measures ANOVA demonstrated significant differences with bat swing velocity (F = 13.19, df 3, p < 0.0001). Pairwise comparisons revealed significant differences in MP+C with MP (p = 0.007); MP+C with NC (p = 0.001), and C with NC (p = 0.009). The results of this study provide evidence of jaw clenching's positive effects on the dynamic, whole-body explosive activity of a bat swing. [ABSTRACT FROM AUTHOR]

We investigated whether post-meal walking (PMW) improved post-prandial glucose and 24h glucose control under free-living conditions among physically inactive young women. METHODS: Young women (Age: 20±1years; percent body fat: 28.2 ± 12%; BMI: 23.8 ± 4.2kg·m−1) completed a randomised crossover study to assess if PMW confers benefit. On the PMW day, women completed three bouts of brisk walks, and on the Control day they were instructed to follow normal habitual activities. Continuous glucose monitors captured post-prandial and 24h glucose, and physical activity monitors tracked physical activity throughout the study. RESULTS: PMW walking increased total daily step count (Control = 9,159 ± 2,962 steps vs. PMW = 14,611±3,891 steps, p<0.001) and activity scores (Control=33.87±1.16 METs·h vs. PMW = 36.11±1.58 METs·h, p < 0.001). PMW led to lower 3h average post-prandial glucose (main effect of condition, p=0.011) and 3h post-prandial area under curve glucose responses (main effect of condition, p = 0.027) compared to the control condition. Post hoc analysis revealed the largest decline occurred after dinner (3h average glucose Control = 7.55±1.21 mmol/L vs. PMW = 6.71 ± 0.80mmol/L, p = 0.039), when insulin sensitivity is typically diminished. Despite improvements in post-prandial glucose control, this did not translate to improvements in 24h glucose control (p > 0.05). CONCLUSION: Physically inactive and metabolically healthy young women, PMW improves post-prandial glucose but not 24h glucose control. [ABSTRACT FROM AUTHOR]

Climbing is a physically demanding discipline, placing significant loads on the finger flexors. Notwithstanding the documented greater endurance capacity of experienced climbers, the mechanisms explaining these training-induced adaptations remain unknown. We therefore investigate whether two non-competing strategies – muscle adaptation and alternate muscle recruitment – may explain the disparity in endurance capacity in participants with different climbing experience. We analysed high-density surface electromyograms (EMGs) from 38 Advanced and Intermediate climbers, during suspension exercises over three different depths (15, 20, 30 mm) using a half-crimp grip position. From the spatial distribution of changes in MeDian Frequency and Root Mean Square values until failure, we assessed how much and how diffusely the myoelectric manifestations of fatigue took place. Advanced climbers exhibited greater endurance, as evidenced by significantly longer failure time (p < 0.009) and lower changes in MDF values (p < 0.013) for the three grip depths. These changes were confined to a small skin region (nearly 25% of the grid size), centred at variable locations across participants. Moreover, lower MDF changes were significantly associated with longer suspension times. Collectively, our results suggest that muscle adaptation rather than load sharing between and within muscles is more likely to explain the improved endurance in experienced climbers. [ABSTRACT FROM AUTHOR]

This study examined the effects of an 8-week horizontal speed deceleration training (HSDT) programme in combination with regular handball-specific training as compared with handball-specific training only in measures of physical fitness in male youth handball players. Thirty-nine players were randomly assigned to either an HSDT group (n = 18; 15.55 ± 0.24 years) or an active-control group (CG; n = 21; 14.59 ± 0.23 years). The results showed significant and large between-group differences at post-test in countermovement jump, change-of-direction speed, and repeated sprint ability (RSA) (all p < 0.01; d = 2.04 and 1.37, 1.39, 1.53, and 1.53 for the CMJ, 505 CoD, RSAbest, RSAaverage, and RSAtotal performances, respectively). The post-hoc-analysis demonstrated significant and large improvements in all measures of physical fitness in the HSDT group (∆2.49% to 16,25%; d = 1.01 to 1,70; all p < 0,01). The CG, however, failed to reach any significant difference in all measures of physical fitness ((∆0.31% to 1.98%; d = 0.15 to 0.22; p = 0.379; p > 0.05). To summarise, an 8-week in-season HSDT programme alongside regular handball-specific training yielded positive effects on various performance measures including jumping ability, CoD speed, and RSA, when compared to handball-specific training alone. These results highlight the potential benefits of integrating HSDT into the training regimen of youth handball athletes during the competitive season. [ABSTRACT FROM AUTHOR]

A large proportion of netball players suffer foot-related problems and pain and are dissatisfied with current netball-specific footwear. To improve the fit and functionality of netball-specific shoes, we must understand the shape of these players' feet and determine whether any sex differences exist. Five hundred and two representative-level netball players (n = 251 male; n = 251 female) had their feet three-dimensionally scanned. We then used a validated MATLAB code to automatically extract 10 measurements to characterise each participant's foot shape. Differences between men and women for the absolute values and those normalised to foot length and stature were identified using independent samples t-tests with a Bonferroni adjusted alpha level. The size and shape of male netball players' feet differed significantly from their female counterparts. Males had significantly larger absolute and normalised foot measurements than females, notably at the ball of the foot, heel and instep (p < 0.001). Netball shoe manufacturers should develop unique lasts for each sex and foot size and should offer a more extensive range of shoe lengths and widths to netball players. Such considerations will help optimise shoe fit and comfort and, in turn, reduce foot-related problems and pain associated with ill-fitting footwear. [ABSTRACT FROM AUTHOR]

In contrast to male football players, research on the nutritional requirements of female football players is limited. This study aimed to assess total daily energy expenditure (TDEE) in professional female football players, along with body composition, physical activity and dietary intake. This observational study included 15 professional football players playing in the highest Dutch Women's League. TDEE was assessed by doubly labelled water over 14 days, along with resting metabolic rate (RMR; ventilated hood), fat-free mass (FFM; dual-energy x-ray absorptiometry), and dietary intake (24-h recalls). Physical activity energy expenditure (PAEE) was derived from subtracting RMR and estimated diet-induced thermogenesis (10%) from TDEE. TDEE was 2882 ± 278 kcal/day (58 ± 5 kcal/kg FFM) and significantly (p < 0.05) correlated with FFM (r = 0.62). PAEE was 1207 ± 213 kcal/d. Weighted energy intake was 2344 kcal [2023–2589]. Carbohydrate intakes were 3.2 ± 0.7, 4.4 ± 1.1 and 5.3 ± 1.9 g/kg body mass for rest, training and match days, respectively, while weighted mean protein intake was 1.9 ± 0.4 g/kg body mass. In conclusion, the energy requirements of professional female football players are moderate to high and can be explained by the substantial PAEE. To fuel these requirements, sports nutritionists should consider shifting the players' focus towards prioritizing adequate carbohydrate intakes, rather than emphasizing high protein consumption. [ABSTRACT FROM AUTHOR]

Understanding adolescents' physical activity levels and underpinning contextual factors is crucial for health promotion. This cross-sectional study, using 24-hour time use diaries and sociodemographic variables from the Longitudinal Study of Australian Children, addressed gaps in understanding of physical activity in the before-school segment (the time between waking up and commencing classes). The study examined a) adolescents' time spent in before-school physical activity, focusing on location and shared presence, and b) sociodemographic correlates of before-school physical activity. Completed diaries by 12–13 year-olds (n = 3,201) revealed that adolescents reported an average of 10.8 minutes of daily before-school physical activity (average segment length: 114 min), mostly classified as active transport (5.7 min). Most before-school physical activity occurred in a location other than home or school (6.1 min) and with peers (6.1 min). Notably, 51% of boys and 60% of girls did not report any before-school physical activity. Through two-part regression, we found that boys, adolescents from single-parent households, and those with longer before-school segments are more likely to report before-school physical activity compared to their counterparts. Before-school initiatives should promote active transport and diverse opportunities in other settings. Research into barriers and facilitators may inform more inclusive and effective promotion strategies, including school-based initiatives. [ABSTRACT FROM AUTHOR]

Volleyball-specific footwear with higher collar heights (a mid-cut shoe) are worn to restrict ankle motion. Reduced ankle dorsiflexion has been associated with increased frontal plane motion and injury risk at the knee. With the high frequency of unilateral landings in volleyball, the purpose of this study was to determine the effect of volleyball-specific shoes and limb dominance on knee landing mechanics in collegiate volleyball players. It was hypothesized that participants would exhibit smaller sagittal plane and greater frontal plane knee joint mechanics in mid-cut and dominant limb and that vertical and posterior directed ground reaction forces would be greater wearing mid-cut, yet similar between limbs. Seventeen female volleyball players performed unilateral landings on each limb in mid-cut and low-top volleyball shoes. For shoe main effects, smaller peak dorsiflexion angle and internal peak plantarflexion moment and greater peak medial ground reaction force were found in the mid-cut but with no impact on knee mechanics. For limb main effects, the internal peak knee abduction moment was greater in the dominant limb. Greater peak lateral ground reaction force was found in the interaction between the non-dominant limb and low-top. Further research is warranted to better understand shoe and limb impact in volleyball players. [ABSTRACT FROM AUTHOR]

This study presents a method for analysing badminton matches based on the concept of perturbations. We transfer this principle to a badminton rally and describe the decisive shot, which turns a balanced situation into an advantage for one team or one player. Our paper proposes an observational system, which models the decisive shots by using four consecutive actions: impulse (the perturbation), follow-up, survival, and convert. To test the objectivity of the operationalization, independent raters analysed six matches in the singles disciplines of the 2022 World Championships. To evaluate rater agreement, Jaccard coefficient and Cohen's kappa were used. Results show an agreement in identifying impulses of J(R1, R2) =.80, while the agreement in classifying the impulse type (positive/negative) reached κ =.70. A comparison of this perturbation-based analysis and last shot analyses shows significantly different results. Direct errors usually occur in the midcourt (56.4%), whereas most negative perturbations originate from the backcourt (40.0%). In contrast to direct winners, mostly originating from a smash (45.5%), most positive perturbations are created by net shots (30.1%). We argue that our method can be complementary to common last shot analyses and provides a possibility to describe players' strengths and weaknesses in more detail. [ABSTRACT FROM AUTHOR]

We sought to determine the effects of blood flow restriction (BFR) on exercise-induced hypoalgesia, specifically using low-load (LL) resistance exercise (30% 1RM) protocols that accounted for each individual's local muscular endurance capabilities. Forty-four participants completed four conditions: (1) 70% of maximal BFR repetitions with blood flow restriction (LL+BFR exercise); (2) 70% maximal BFR repetitions without LL+BFR (LL exercise); (3) 70% maximal free flow repetitions (LL+EFFORT exercise); (4) time-matched, non-exercise control (CON). Pressure pain threshold (PPT) was measured before and after exercise. Ischaemic pain threshold and tolerance was assessed only at post. The change in upper body PPT was greater for LL+BFR exercise compared to LL exercise [difference of 0.15 (0.35) kg/cm2], LL+EFFORT exercise [difference of 0.23 (0.45) kg/cm2], and the CON condition. The change in lower body PPT was greater for LL+BFR exercise compared to LL exercise [difference of 0.40 (0.55) kg/cm2], LL+EFFORT exercise [difference of 0.36 (0.62) kg/cm2], and the CON condition. Ischaemic pain thresholds and tolerances did not change. Submaximal exercise with BFR resulted in systemic increases in PPT but had no influence on ischaemic pain sensitivity. This effect is likely unique to BFR as we did not see changes in the effort matched free flow condition. [ABSTRACT FROM AUTHOR]

The effects obtained from resistance training depend on the exercise range of motion (ROM) performed. We aimed to examine the acute effects of different exercise ROM resistance training on the plantar flexor muscles. Eighteen healthy untrained male adults participated in three conditions: calf raises in 1) partial condition [final (short muscle length) partial ROM], 2) full condition (full ROM), and 3) control condition. The ankle dorsiflexion (DF) ROM, passive torque at DF ROM, passive stiffness of muscle-tendon unit, and maximal voluntary isometric contraction (MVC-ISO) torque were measured before and immediately after the interventions. There were significant increases in DF ROM, passive torque at DF ROM, and a decrease in MVC-ISO, but no significant interaction in passive stiffness. Post hoc test, DF ROM demonstrated moderate magnitude increases in the full condition compared to the partial (p = 0.023, d = 0.74) and control (p = 0.003, d = 0.71) conditions. Passive torque at DF ROM also showed moderate magnitude increases in the full condition compared to the control condition (p = 0.016, d = 0.69). MVC-ISO had a moderate magnitude decrease in the full condition compared to the control condition (p = 0.018, d=−0.53). Resistance training in the full ROM acutely increases joint ROM to a greater extent than final partial ROM, most likely due to stretch tolerance. [ABSTRACT FROM AUTHOR]

This study investigated the effect of external (EC) and internal coaching cues (IC), analogies with a directional component (ADC) on sprint (20 m) and vertical jump performance in academy soccer players (n = 20). A repeated-measures analysis, with post-hoc comparisons, was used to identify any differences between these cues and a neutral (control) cue. Significant differences were found for both sprint (p < 0.001) and jump (p = 0.022) comparisons among cue types. In post-hoc analyses for the 20 m sprint, significant differences were observed between the EC and the IC, favouring the EC (p < 0.01, ES = 1.27 [CI: 0.24, 2.30]), and "away" ADC and the IC, favouring the "away" ADC (p < 0.01, ES = 1.21 [CI: 0.19, 2.22]). No other cues showed significant differences. For vertical jump, there was just one significant difference between comparisons, that being for the "away" ADC vs. the neutral cue, favouring the latter (p = 0.023, ES = 0.4 [CI: −0.04 to 0.84]). It appears that ECs and ADCs are most effective when coaching sprinting performance in academy soccer players. However, simply encouraging maximal effort from a youth athlete also appears to be a reasonable cueing strategy to drive performance in youth athletes. [ABSTRACT FROM AUTHOR]

This study aimed to analyse the relationship between the maturational state and contextual factors with future basketball career success in Under-16 (U16) Portuguese youth preparing for the U16 European Basketball Championships. Eighty-five Under-15 (U15) and U16 male basketball players (height: 189.7 ± 6.53 cm; body mass: 81.1 ± 9.96 kg; the age of peak height velocity: 13.3 ± 0.7 y) were selected by the Portuguese national coaching staff to participate in a national team training camp in 2016, 2017, and 2018 years. A binary logistic regression was employed to identify the influence of maturation, born quartile, demographic, geographic and economic characteristics, and sport career (i.e., drop out during first season and chance of playing professionally). Early maturing players were typically classified as inside players. Training experience and predicted adult height, and type of first club were able to predict players who dropped out during their first season at senior level (both p < 0.01). No variables were able to predict who played in a professional league during their first season at senior level. Practitioners should use these data to consider how national level basketball players are identified and developed, but also keep in mind of their specific contextual factors. [ABSTRACT FROM AUTHOR]

Decision-making in team sports necessitates monitoring multiple performers located at different distances (i.e., viewing eccentricities) from a critical information source. The processing of peripheral information is generally impaired under anxiety and when responding to stimuli located at larger eccentricities. These hypotheses have not been sufficiently tested in dynamic performance environments. We examined how pressure and eccentricities affect decision-making and visual behaviour in 4v4 basketball defensive scenarios using a head mounted display. Experienced players monitored plays from the first-person perspective (centre position) and made defensive steps towards opponents threatening the basket from different eccentricities under low- and high-pressure. To tax working memory, participants simultaneously performed a backward counting task. Players responded slower and with lower accuracy to opponents at larger eccentricities. Players mostly fixated on the ball-carrier, but over 50% of fixations were located on peripheral players, indicating that information in the periphery must be frequently updated with foveal vision (i.e., pivot strategy). When pressured, participants increased mental effort and improved counting performance; however, gaze behaviour and decision-making were relatively unaffected. Findings suggest that basketball players respond more quickly to opponents positioned at lower compared to higher eccentricities at the cost of impaired responses to opponents in the periphery. [ABSTRACT FROM AUTHOR]

Physical activity during pregnancy has numerous health benefits for the woman and the foetus. The current study investigated physical activity engagement and its predictors among pregnant Chinese women during the first trimester. A total of 687 pregnant women completed the Pregnancy Physical Activity Questionnaire. Bivariate and multivariate logistic regression were used to analyse the data. The current physical activity guidelines were not met by 64.3% of respondents. Women with higher levels of physical activity self-efficacy (aOR = 0.96; 95% CI: 0.92–0.99) and social support (aOR = 0.95; 95% CI: 0.94–0.97) had lower odds of not meeting the current physical activity guidelines. Women who were aged < 35 years (aOR = 1.85; 95% CI: 1.02–3.34), had lower education (aOR = 1.63; 95% CI: 1.04–2.55), were primiparous (aOR = 11.03; 95% CI: 6.98–17.44), were unsure of their delivery mode (aOR = 2.32; 95% CI: 1.95–5.64), and those who had higher levels of pregnancy-associated discomfort (aOR = 1.10; 95% CI: 1.03–1.19) had higher odds of not meeting the current physical activity guidelines. The current study suggests that healthcare professionals should assess physical activity engagement during routine antenatal care and increase efforts to strengthen pregnant women's self-efficacy and social support to promote physical activity engagement during the first trimester. [ABSTRACT FROM AUTHOR]

This study aimed to assess the effectiveness of foam rolling as a post-match recovery tool in basketball. Using a crossover design, 13 female players completed two simulated matches, followed by foam rolling (FR) or placebo (CON). Countermovement jump height (CMJ), heart rate variability (Ln-rMSSD), muscle soreness (VAS), perceived recovery (TQR) and fatigue (Rating-of-Fatigue) were recorded at pre-match, post-match, post-recovery and 24 h post-match. No significant effect of time*intervention and intervention were found for any variable (p > 0.05), while a significant effect of time (p < 0.01) was reported for all variables. Post-hoc analyses revealed lower CMJ and Ln-rMSSD at post-match compared with all other time points (p < 0.001), increases in pre-match VAS scores at all subsequent time points (p < 0.01), and worse TQR and Rating-of-Fatigue scores from pre-to-post-match and pre-match-to-post-recovery (p < 0.01), except for unchanged TQR values from pre-match-to-post-recovery in FR (p > 0.05). Overall, the present data suggest that foam rolling was generally ineffective for improving post-exercise recovery in female basketball players after a single match. Future research investigating the effectiveness of foam rolling in players of different sex, age and/or competitive level is warranted to provide further insight on the topic. [ABSTRACT FROM AUTHOR]

Perceived physical exertion is increased when exercise is performed on metformin treatment, but the clinical relevance of this is unknown. In this post hoc analysis of a randomized, controlled trial, we investigated whether metformin treatment was associated with lower levels of free-living physical activity. Ninety individuals with overweight/obesity (BMI>25 m2/kg) and HbA1c-defined prediabetes (39-47 mmol/mol) were randomized to treatment with dapagliflozin (SGLT2-inhibitor; 10 mg once daily, n=30), metformin (850 mg twice daily, n=30) or no treatment (control, n=30) for 13 weeks in a parallel-group, open-label trial. Before (baseline), during (6 weeks) and immediately after (13 weeks) cessation of treatment, a 6-day assessment of physical activity and sedentary behaviour was performed using accelerometer-based physical activity monitors. Intention-to-treat analyses revealed no within-group changes or differences in change between the groups for any measures of physical activity or sedentary behaviour at neither 6 nor 13 weeks. Short-term metformin treatment does not reduce free-living physical activity level in individuals with overweight/obesity and HbA1c-defined prediabetes. [ABSTRACT FROM AUTHOR]

Differences in workload exist between netball playing positions and competition levels, but no research has compared workloads experienced by the same elite players during national and international competitions. This study collected internal (heart rate) and external (PlayerLoad·min−1) workload data per match quarter from 44 players during a national competition and 12 players during an international competition. Nine players played in both competitions. Linear mixed models compared percentage of match quarter in each heart rate zone and PlayerLoad·min−1 between competitions for each playing position. Workloads against low- and high-ranked international opponents were also compared. Internal workloads were greater in national compared to international competition for GD and WD positions. PlayerLoad·min−1 was significantly higher by 8–13% in the national competition for positions WD and C, and by 5–8% in the international competition for GD and GA. Positional differences may indicate a role of the team's tactical style of play. Workloads were generally greater against higher- rather than lower-ranked international opponents. These results indicate that tactical factors in combination with playing position and opposition characteristics should be considered when preparing physically for matches. [ABSTRACT FROM AUTHOR]

The main purpose of this study was to determine the effect of a psychological training intervention based on emotional regulation on anxiety and climbing ability in women climbers with fear of falling. A secondary aim was to compare the outcomes of climbing ability, anxiety, self-confidence and interoceptive awareness (IA) between the psychological group (PG), a training (TG) and a control group. Self-reported climbing ability, anxiety and IA were assessed using Competitive State Anxiety Inventory-2 and the Multidimensional Assessment of Interoceptive Awareness questionnaire. Results indicated a significant improvement in climbing ability for both PG and TG. The PG showed a significant reduction in cognitive and somatic anxiety, while the TG only exhibited a reduction in cognitive anxiety. Moreover, the PG demonstrated a greater significant increase in self-confidence compared to the TG. IA improved in five subscales for the PG, whereas the TG changed in only two subscales. In conclusion, a psychological training intervention focusing on emotional regulation might contribute to improvements in IA, reduced anxiety levels, and enhancements in climbing ability and self-confidence among women climbers facing fear of falling. [ABSTRACT FROM AUTHOR]

Two factors that decrease the replicability of studies in the scientific literature are publication bias and studies with underpowered desgins. One way to ensure that studies have adequate statistical power to detect the effect size of interest is by conducting a-priori power analyses. Yet, a previous editorial published in the Journal of Sports Sciences reported a median sample size of 19 and the scarce usage of a-priori power analyses. We meta-analysed 89 studies from the same journal to assess the presence and extent of publication bias, as well as the average statistical power, by conducting a z-curve analysis. In a larger sample of 174 studies, we also examined a) the usage, reporting practices and reproducibility of a-priori power analyses; and b) the prevalence of reporting practices of t-statistic or F-ratio, degrees of freedom, exact p-values, effect sizes and confidence intervals. Our results indicate that there was some indication of publication bias and the average observed power was low (53% for significant and non-significant findings and 61% for only significant findings). Finally, the usage and reporting practices of a-priori power analyses as well as statistical results including test statistics, effect sizes and confidence intervals were suboptimal. [ABSTRACT FROM AUTHOR]

Meta-analysis has become commonplace within sport and exercise science for synthesising and summarising empirical studies. However, most research in the field focuses upon mean effects, particularly the effects of interventions to improve outcomes such as fitness or performance. It is thought that individual responses to interventions vary considerably. Hence, interest has increased in exploring precision or personalised exercise approaches. Not only is the mean often affected by interventions, but variation may also be impacted. Exploration of variation in studies such as randomised controlled trials (RCTs) can yield insight into interindividual heterogeneity in response to interventions and help determine generalisability of effects. Yet, larger samples sizes than those used for typical mean effects are required when probing variation. Thus, in a field with small samples such as sport and exercise science, exploration of variation through a meta-analytic framework is appealing. Despite the value of embracing and exploring variation alongside mean effects in sport and exercise science, it is rarely applied to research synthesis through meta-analysis. We introduce and evaluate different effect size calculations along with models for meta-analysis of variation using relatable examples from resistance training RCTs. [ABSTRACT FROM AUTHOR]

Experiencing mental fatigue (MF) before an orienteering race can lead to a slower completion time. This study aimed to explore the changes in perceived MF, mood and other psychological responses during an orienteering competition. Sixteen national level orienteering athletes (20.8 ± 4.9 years) provided informed consent and completed the online surveys, before and immediately after each race, and 24- and 48-hours post competition (48POST). This study measured MF, physical fatigue, stress, tiredness and motivation using 0–100 Visual Analogue Scale, and the mood was assessed using The Brunel Mood Scale (BRUMS). A moderate to large increase in MF (ES = 0.93 [0.54 to 1.31]), BRUMS fatigue (ES = 0.61 [0.3 to 0.92]), and PF (ES = 1.21 [0.81 to 1.61]) was reported following orienteering races. A small increase in tiredness and BRUMS confusion, and a small decrease in motivation, stress and BRUMS vigour was also reported. There was a delay in recovering from the MF elicited by competition, with a small increase in MF (ES = 0.54 [0.08 to 1.15]) at 48POST compared to the pre-competition value. This study found that orienteers experience MF during competition and have a delayed recovery that can last up to two days after the competition. [ABSTRACT FROM AUTHOR]

This study aimed to demonstrate the differences in spatiotemporal and ground reaction force (GRF) variables during overground sprinting between performance levels for female and male sprinters with providing normative data during the entire acceleration phase. Forty-four female and 102 male sprinters performed 60-m sprints, during which the spatiotemporal and GRF variables were obtained using a long force platform system. Female and male sprinters were each allocated into four groups based on their maximal speed (7.5–9.5 m/s and 8.5–10.5 m/s, respectively) with 0.5 m/s intervals, and average values for 50-m distance were calculated. Using the GRF data, normative data for four groups of female and male sprinters were successfully obtained. For female sprinters using average values of all steps, there were differences between performance levels for step frequency (SF) and support time (ST), all impulses, and all mean forces. For male sprinters using average values of all steps, there were differences between performance levels for SF, ST and flight time, all impulses except for braking impulse, and all of the mean forces. The normative data indicate that most of the spatiotemporal and GRF variables may be changed, particularly increasing SF and propulsive force, when sprint performance is improved. [ABSTRACT FROM AUTHOR]

This study aims to determine the validity of the lower extremity joint kinematics measured by inertial measurement units (IMUs) in non-rearfoot strike pattern (NRFS) runners across different speeds. Fifteen NRFS runners completed three 2-min running tests on a treadmill in random order at 8, 10 and 12 km/h, whilst data were synchronously collected using the IMU system and an optical motion capture system. Before the offset was corrected, the validity of the knee angle waveform was higher than that of the hip and ankle; after the offset was corrected, the validity increased in all three joints. The correlation between the touchdown angles in the sagittal plane measured by the two systems was relatively high after the offset was corrected. The running speed influenced the offset-corrected measurements, with higher error values at higher speeds. The IMU system was able to provide measurements of running kinematics in the sagittal plane of NRFS runners at different running speeds but was unable to reliably measure motion in the frontal and horizontal planes. Future research should analyse the 3D gait of NRFS runners under a larger range of speed conditions to provide evidentiary support for the use of IMUs in running analysis outside the laboratory. [ABSTRACT FROM AUTHOR]

This study investigated micro-pacing strategies during sit para-biathlon. Six elite sit para-biathletes wore a positioning system device during the world-championships in three different competition formats (Sprint, Middle-distance, and Long-distance). Total Skiing Time (TST), penalty-time, shooting-time, and Total Race Time (TRT) were analysed. One-way analyses of variance were used to compare the relative contributions of TST, penalty-time, and shooting-time to TRT across the three race formats. Statistical parametric mapping (SPM) was used to determine the course positions (clusters) where instantaneous skiing speed was significantly associated with TST. The contribution of TST to TRT was lower for the Long-distance (80 ± 6%) compared to the Sprint (86 ± 5%) and Middle-distance (86 ± 3%) races, however this difference was not statistically significant (p > 0.05). The proportional contribution of penalty-time to TRT was significantly greater (p < 0.05) for the Long-distance (13 ± 6%) compared to the Sprint (5 ± 4%) and Middle-distance (4 ± 3%) races. Statistical parametric mapping (SPM) revealed specific clusters where instantaneous skiing speed was significantly associated with TST. For example, over all laps during the Long-distance race, the fastest athlete gained 6.5 s over the slowest athlete in the section with the steepest uphill. Overall, these findings can provide insights into pacing strategies and help para-biathlon coaches and athletes optimise training programmes to improve performance. [ABSTRACT FROM AUTHOR]

This study compared physical activity metrics from the activPAL (AP) worn on the thigh with the ActiGraph worn on the non-dominant wrist using open-source methods. Measures included average acceleration, intensity gradient (IG) and the minimum acceleration value of the most active X mins (MX). Fifty-two children (26 boys; age: 10.4 ± 0.6 years) provided≥1 day (24 h) of concurrent wear time from the activPAL and ActiGraph. Measures tended to be lower from the activPAL versus the ActiGraph. Poor agreement was evident for average acceleration but good for the IG. For the IG, the absolute and relative zones needed to reach equivalence was 4% and 0.4 SDs, respectively and for average acceleration were 10% and 1.2 SDs, respectively. Good agreement was evident for M60, M30, M20, M15 and M10 between devices. Regardless of the reference device used, equivalent estimates for the intensity gradient, M60, M30, M20, M15 and M10 were observed with relative and absolute equivalence zones being≤4% and≤0.5 SDs, respectively. The IG, M60, M30, M20, M15 and M10 appear good candidates for comparing activity data collected from the activPAL and ActiGraph. Future research can use the AP to report on sedentary behaviours as well as PA outcomes. [ABSTRACT FROM AUTHOR]

Despite overwhelming adoption of wearable fitness trackers (WFT), it is unclear if they affect physical activity (PA) engagement or PA motivation. We hypothesized that combining a WFT with an effective intervention, motivational interviewing (MI), would positively influence both motivation and PA. A 12-week randomized controlled trial was conducted in 40 adults who did not meet PA recommendations. The four conditions were: a PA education (Educational control, n = 10), a WFT (WFT, n = 10), bi-weekly MI sessions (MI, n = 10), or both interventions (WFT+, n = 10). Motivation and PA were measured through an online survey and actigraphy pre- and post-intervention. Both the WFT+ and MI groups improved autonomous forms and decreased controlled forms of motivation. They also had higher basic psychological needs scores when compared to the Education group post-intervention. We detected no changes in PA. High autonomous motivation at baseline predicted higher post-intervention PA in the WFT+ group but predicted lower post-intervention PA in the WFT group. Results suggests that MI alone or with a WFT can improve basic psychological needs and autonomous forms of motivation for PA, but not PA participation. Individual differences in motivation at baseline may moderate the effect of a WFT on PA. This study was registered at clinicaltrials.gov (NCT490014). [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the effect of endurance training individually guided by objective (Heart Rate Variability-HRV) or self-report measure of stress (DALDA-questionnaire) in comparison to predefined endurance training prescription for improving endurance performance in recreational runners. After a 2-week preliminary baseline period to establish resting HRV and self-reported measure of stress, thirty-six male recreational runners were randomly assigned to HRV-guided (GHRV;n = 12), DALDA-guided (GD; n = 12) or predefined training (GT; n = 12) prescription groups. Before and after 5-weeks of endurance training, participants performed a track field peak velocity (Vpeak_TF), time limit (Tlim) at 100% of Vpeak_TF and 5 km time-trial (5 km TT) tests. GD lead to higher improvements in Vpeak_TF (8.4 ± 1.8%; ES = 1.41) and 5 km TT (−12.8 ± 4.2%; ES = −1.97), than GHRV (6.6 ± 1.5% and −8.3 ± 2.8%; ES = −1.20; 1.24) and GT (4.9 ± 1.5% and −6.0 ± 3.3%; ES = −0.82; 0.68), respectively, with no differences for Tlim. Self-report measures of stress may be used to individualize endurance training prescription on a daily basis leading to better performance enhancement, which may be used with HRV for a holistic understanding of daily training-induce adaptations. [ABSTRACT FROM AUTHOR]

The objective of this study was to compare head impact magnitudes and time between impacts among positions in Canadian high-school football. Thirty nine players from two high-school football teams were recruited and assigned a position profile: Profile 1 (quarterback, receiver, defensive back, kicker), Profile 2 (linebacker, running back), and Profile 3 (linemen). Players wore instrumented mouthguards to measure peak magnitudes of linear and angular acceleration and velocity for each head impact throughout the season. A principal component analysis reduced the dimensionality of biomechanical variables, resulting in one principal component (PC1) score assigned to every impact. Time between impacts was calculated by subtracting the timestamps of subsequent head impacts within a session. Significant differences in PC1 scores and time between impacts occurred between playing position profiles (ps<0.001). Post-hoc comparisons determined that PC1 was greatest in Profile 2, followed by Profiles 1 and 3. Time between impacts was lowest in Profile 3, followed by Profiles 2 and 1. This study delivers a new method of reducing the multidimensionality of head impact magnitudes and suggests different Canadian high-school football playing positions experience different head impact magnitudes and frequencies, which is important for monitoring concussion and repetitive head impact exposure. [ABSTRACT FROM AUTHOR]

This study aimed to examine the effects of substitute player allowance per match on running performance in Japanese professional football over three consecutive seasons with different numbers of maximum substitutes. Match running performance was obtained from all outfield players in the official matches of the 1st Division of the Japan Professional Football League over three seasons (2019/2020/2021; 22291 player files) by a 4th generation TRACAB® system which provided the total distance covered (TD) and the number of sprinting runs (SP; ≥24.0 km/h for≥1.0 s). The players were divided according to play time: full match (STA), replaced during match (REP), and substitutes during match (SUB). The number of SUBs increased significantly from 2019 to 2021 (p < 0.05). SUB had a significantly higher average speed than STA and REP. The analysis of covariance with the number of recovery days, ambient temperature, and relative humidity as covariates revealed that the TD and SP significantly differed based on the number of SUBs (p < 0.05). Stepwise regression analysis showed that the number of SUBs significantly contributed to the TD and SP. These results suggest that the new law, which increased the maximum SUB allowance from three to five, improved the match running performance in Japanese professional football. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyse differences in velocity, distance travelled and manoeuvres performed by Olympic sailors of the RS:X class using a GPS device. Fifty-three Olympic sailors of the RS:X class (28 males and 25 females) who competed in a World Championship were selected. The sample was divided into tertiles (T1, T2 and T3) according to their classification in the competition. Using a GPS device during the competition, mean velocity (VM), velocity made good (VMG), manoeuvres and distances in three different courses (upwind, reaching and downwind) were assessed during a regatta. Significant differences were found based on performance level in upwind (p < 0.001; η p 2 = 0.288), sailors of T1 covering a shorter distance compared to those of T2 (p < 0.009) and T3 (p < 0.001). Regarding VMG, an effect was observed for performance level in upwind (p < 0.001; η p 2 = 0.718), reaching (p < 0.001; η p 2 = 0.469) and downwind (p < 0.001; η p 2 = 0.575). Females covered a shorter distance compared to the males in upwind (p < 0.001; η p 2 = 0.639) and downwind (p < 0.001; η p 2 = 0.903). Distance and VMG are significant variables for establishing differences in performance level among Olympic sailors of the RS:X class when the wind speed is in a range of 8–21 knots. [ABSTRACT FROM AUTHOR]

Gel pack temperatures were compared for responses to thermal, physiological, perceptual, and ergogenic indices from healthy women (n = 12) and men (n = 8). They did three rowing workouts to identify an ideal temperature. In a randomised sequence, and as subjects wore gloves equipped with mesh pouches during workouts, gel packs at one of the three average temperatures (10.6, 12.6, or 14.9°C) were inserted into the pouches. Data were collected before, during and after multi-stage workouts. Thermal, physiological, and perceptual data were each compared with three-factor (condition, gender, time) mixed effect model ANCOVAs, with repeated measures for condition and time, and gender as a between subjects' factor. Distance rowed was assessed with two-factor (condition, gender) mixed effect model ANCOVAs, with repeated measures for condition, and gender as a between subjects' factor. Within-subject contrasts was the post-hoc, and α = 0.05 denoted significance. Despite small differences for distance rowed, many dependent variables had significant inter-condition effects, whereby 10.6°C gel packs had the best thermal and physiological responses. The 10.6°C temperature 1): likely removed the most body heat, perhaps through cold-induced vasodilation and, 2): may be optimal, as it evoked the best thermal and physiological responses. [ABSTRACT FROM AUTHOR]

This study examined 503 power-hitting strokes that resulted in the maximum of 6-runs being scored in international men's one-day and T20 cricket. Chi-Squared analyses were conducted to determine if performance and situational variables were associated with the distribution (direction) of aerial power-hitting strokes. Results revealed that bowling length, bowling line, bowler type and powerplays were all significantly (p < 0.001) associated with ball-hitting distribution. Post-hoc analysis of the standardised residuals revealed that greater than expected 6ʹs were scored behind square and were associated with short-pitched bowling, fast bowling and the power-play. Similarly, bowling the half-volley length and the outside off line resulted in greater than expected 6ʹs on the off-side. The results suggest that bowlers should try to avoid offering width outside the off stump as well as bowling the half-volley and short-pitched lengths as these bowling lines and lengths present batters with greater opportunities to score maximum runs. Fast bowling is revealed to be more susceptible to power-hitting strokes than spin bowling. Conversely, batters may wish to target the areas behind square or on the off-side for opportunities to score maximum runs, and they should look to take full advantage of the powerplay field restrictions. [ABSTRACT FROM AUTHOR]

Exercise interventions targeting older adults often focus on acute changes, but lasting improvements require the adoption of long-term, independent exercise habits. This study aimed to assess the influence of eight-weeks of resistance training (SSSH) on clinically relevant fall-risk indicators in older adults and to evaluate if SSSH participation altered independent exercise engagement 12 months later. Sixty adults aged 50 yrs+ were randomised into SSSH, Walk, or Control groups and completed questionnaires and muscle strength and flexibility tests pre/post 8 weeks. SSSH and Walk met 2x/wk for 60 min. Twelve months later 24 participants also completed a follow-up survey amid COVID-19 restrictions. Eight-week group changes were analysed using one-way ANOVA with Bonferroni post hoc analyses, and survey responses were compared using paired t-tests with a Bonferroni correction. SSSH demonstrated greater absolute changes over 8 weeks in sleep quality, activity engagement, 30-second-sit-to-stand and upper-body flexibility than Walk or Controls (p < 0.05). Twelve months later, SSSH participants reported significantly increasing independent resistance (+68), aerobic (+125) and flexibility (+26) training minutes per week (all p < 0.01). In conclusion, SSSH reduced fall risk in 8 weeks and sparked older adults to begin and sustain positive exercise habits 12 months later, despite COVID-19 restrictions. [ABSTRACT FROM AUTHOR]

The present study explored the mediation role of past exercise adherence, self-reported frequency and intentions in the association between past experience and future exercise adherence. In total, 431 exercisers (female = 216; male = 215) aged 18 and 64 years, engaged in fitness activities such as group fitness classes and resistance training, were included in the analysis. Serial mediation procedures were employed to examine the direct, indirect, and total indirect effects among variables. The predictor variable and all mediators displayed a positive and significant association with future six-month adherence. Past six-month exercise adherence displayed the most significant association with future six-month adherence. The sequential indirect path from exercise experience → past six-months adherence → self-reported frequency → intentions future six-months adherence displayed a positive and significant effect (β =.19 [CI95% =.09,.31]), presenting a partial mediation effect. Past behaviour is the most significant predictor of future adherence, and thus interventions should be based on promoting consistent exercise frequency. Professionals working in the fitness centre context can identify possible dropouts based on their past behaviour and intentions to be physically active in the future. [ABSTRACT FROM AUTHOR]

The fact that potentially skilled, but biologically later-maturing athletes are less likely to be selected into talent development programmes (TDP) can represent a failure of Talent Identification (TID) in sports. To overcome maturation selection biases, maturation independent TID should be established to include less mature, but talented athletes in TDP more frequently. Using a randomised parallel-group design, this study aimed to evaluate the effect of labelling under-11 (U11) Swiss male youth football players (n = 24, age = 11.0 ± 0.3 years) via maturation-ordered shirt numbers during rank assessment by talent scouts (n = 83, scout experience = 4.8 ± 2.4 years). Following observation of video recorded selection tournaments, player-labelling "informed" scouts were significantly more likely to rank less mature players higher on their player potential, t(81) = 2.57, p =.012, d = −0.6, 95% CI [−1.00, −0.13], than "uninformed" scouts. As altered rankings assisted less mature players, player-labelling may offer a practical and feasible strategy to improve TID by removing possible maturation selection biases. To address maturation selection biases and the potential positive impact of player-labelling more broadly, further research on both male and female athletes in various age categories and sports contexts is recommended. [ABSTRACT FROM AUTHOR]

Besides examining upper and lower limb morphological and functional asymmetry magnitudes, this study examined the relationship between lean mass and functional asymmetry in terms of magnitude and direction in 41 youth tennis players versus 41 controls. Asymmetry magnitude was determined using anthropometric measurements (circumferences, widths), bioelectrical impedance analysis (lean mass) and a test battery (handgrip strength, seated medicine ball throw, plate tapping, single leg countermovement jump, single leg forward hop test, 6 m single leg hop test, 505 change of direction). ANOVAs compared the dominant (overall highest/best value) against the non-dominant (highest/best value of opposing limb) result. Linear regressions explored the relationship between lean mass and functional asymmetry magnitudes. Kappa coefficients examined asymmetry direction consistency between the limb displaying the highest lean mass value and the limb performing dominantly across tests. Significant asymmetry magnitudes (p < 0.05) were found for all upper and lower limb outcome measures. No significant relationship was apparent between lean mass and functional asymmetry magnitude (r-value = −0.283–0.262). Despite finding (almost) perfect consistency in asymmetry direction (k-value = 0.84–1.00) for the upper limb, poor to slight consistency (k-value = −0.03–0.15) was found for the lower limb. Therefore, lean mass and functional asymmetry should be examined independently. [ABSTRACT FROM AUTHOR]

This study aimed to examine the reliability and validity of Global School-based Student Health Survey (GSHS) to measure 24-hour movement behaviours (moderate-to-vigorous physical activity - MVPA; sedentary behaviour in the form of recreational screen time - ST; and sleep) in Saudi Arabian youths. A total of 120 (50% female) participants aged 12–15 years old were recruited from eight Saudi public middle schools. Participants completed GSHS survey twice and wore GENEActiv accelerometers for seven consecutive days and completed a diary log. ICC indicated moderate reliability in all 24-hour movement behaviours (ICC = 0.41 - 0.60), whereas ST and sleep were strongly reliable for females only (ICC = 0.61 - 0.80). Kappa agreements for all 24-hr movement behaviours were moderate (k = 0.41 - 0.60), but fair in MVPA and ST for males only (k = 0.21 - 0.40). Spearman's indicated low validity (r = 0.1 - 0.3) in MVPA and sleep between GSHS and GENEActiv. However, kappa test results indicated poor-to-slight agreements (k = <0.00 - 0.2) in MVPA and sleep, but fair in MVPA for males only (k = 0.21 - 0.4). GSHS provided good reliability for single items of 24-hour movement behaviours, and the validity was acceptable and in line with other comparable questionnaires. [ABSTRACT FROM AUTHOR]

This study aimed to measure the contribution of each body segment to the production of total body kinetic energy (KE) during a 40-m sprint. Nine recreational sprinters performed two 40-m sprints wearing a MVN Biomech suit (Xsens). Data recorded were used to calculate total body KE, and the KE of each segment. The KE of each segment was then expressed as a percentage of the total body KE. We divided the sprint into three phases: 1 – start to maximal power (Pmax), 2 – Pmax to maximal velocity (Vmax), and 3 – Vmax to the end of the 40 m. Total body KE increased from the start to the end of the 40-m sprint (from 331.3 ± 68.4 J in phase 1 to 2378.8 ± 233.0 J in phase 3; p ≤ 0.001). The contribution of the head–trunk increased (from 39.5 ± 2.4% to 46.3 ± 1.1%; p ≤ 0.05). Contribution of the upper and lower limbs decreased over the three phases (respectively from 15.7 ± 2.5% to 10.6 ± 0.6% and from 44.8 ± 2.1% to 43.1 ± 1.5%; p ≤ 0.05). This study revealed the important contribution of the trunk to forward propulsion throughout the entire acceleration phase. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine whether there are differences in the accuracy and consistency of repeated lawn bowl deliveries between different bowling conditions and to describe the bias of bowls that missed the target (jack). Twenty-seven elite lawn bowl athletes were recruited to partake in the study. Participants delivered 16 bowls in four conditions: (i) forehand and (ii) backhand towards a target 23 metres away and (iii) forehand and (iv) backhand towards a target 27 metres away. The resting position of each bowl relative to the jack was described in terms of absolute displacement, width displacement and length displacement. For each participant and each condition, the average absolute displacement of deliveries was calculated as a measure of accuracy; the average width and length displacement was used to describe the bias of deliveries; and the bivariate variable error of absolute displacement was calculated as a measure of consistency. The forehand towards a target 23 metres away was significantly less accurate and consistent when compared with other conditions. There was a bias for greater width displacement of both forehand deliveries (p < 0.001). Analysing lawn bowls in this detail provides specific areas for coaching to improve lawn bowling performance. [ABSTRACT FROM AUTHOR]

This study aimed to contrast the effects of power training (PT) and plyometric-jump-training (PJT) programmes on measures of physical fitness in prepubertal male soccer players. Thirty-three participants were randomly allocated to PT group (n = 11), PJT group (n = 11), and an active control group (CG; n = 11). Before and after 12 weeks of training, tests were performed for the assessment of sprint-speed , change-of-direction (CoD) speed, muscular strength , and aerobic-endurance (AE). Findings indicated significant group×time interaction effects for all sprint-speed intervals, CoD speed, AE, and strength (d = 0.20–0.32). Post-hoc analyses revealed significant, moderate-to-large improvements in all sprint-speed intervals, CoD speed, AE, and muscle strength following PT (ES = 0.71 to 1.38). The PJT induced significant, moderate-to-large enhancements in 10 m, 20 m, and 30 m sprint, CoD speed, and AE (ES = 0.51 to 0.96) with no significant changes for 5 m sprint-speed and muscle strength (ES = 0.71 and 0.16, respectively). No significant pre-post changes were observed for the CG. Overall, PT and PJT are effective means to improve various measures of physical fitness in prepubertal male soccer players. Notably, to additionally improve acceleration and muscle strength, PT has an advantage over PJT. [ABSTRACT FROM AUTHOR]

To develop a statistical model of winning times for international swimming events with the aim of predicting winning time distributions and the probability of winning for the 2020 and 2024 Olympic Games. The data set included first and third place times from all individual swimming events from the Olympics and World Championships from 1990 to 2019. We compared different model formulations fitted with Bayesian inference to obtain predictive distributions; comparisons were based on mean percentage error in out-of-sample predictions of Olympics and World Championships winning swim times from 2011 to 2019. The Bayesian time series regression model, comprising auto-regressive and moving average terms and other predictors, had the smallest mean prediction error of 0.57% (CI 0.46–0.74%). For context, using the respective previous Olympics or World Championships winning time resulted in a mean prediction error of 0.70% (CI 0.59–0.82%). The Olympics were on average 0.5% (CI 0.3–0.7%) faster than World Championships over the study period. The model computes the posterior predictive distribution, which allows coaches and athletes to evaluate the probability of winning given an individual's swim time, and the probability of being faster or slower than the previous winning time or even the world record. [ABSTRACT FROM AUTHOR]

Although coaching is a co-created process, researchers investigating the psychological aspects of Olympic coaching have tended to overlook the perceptions of athletes and whether these distinguish between performance-related outcomes. The objective of this research was to examine whether athletes' perceptions of their coaches discriminate between world-leading (i.e., Olympic gold medal winning) and world-class (i.e., Olympic non-gold medal winning) coaches. Observer-reported psychometric questionnaires were completed by 38 Olympic swimmers who had collectively won 59 Olympic medals, of which 31 were gold. The questionnaires assessed perceptions of 12 variables within the Big Five personality traits, the dark triad, and emotional intelligence, and the data was analyzed using three one-way multivariate analysis of variance and follow-up univariate F-tests. The results showed that world-leading coaches were perceived to be significantly higher on conscientiousness, openness to experience, perception of emotion, and management of others emotion, and lower on narcissism, than world-class coaches. This suggests that athletes' perceptions of their coaches may discriminate between world-leading and world-class coaches. The implications for coaches' psychological development are discussed and compared with previously reported Olympic coaches' perceptions of themselves. [ABSTRACT FROM AUTHOR]

The penalty kick in soccer is arguably one of the most highly visible and high-pressured sporting situations in the world. This study examined the effect of a high-pressure protocol on penalty shooting performance, and the associated psychological and psychophysiological responses to, and perceptions of that protocol. A sequential mixed-method research design was employed wherein the experimental condition consisted of a repeated-measures design with pressure as the within-participants factor (low-pressure, high-pressure). Quantitative data collection was complemented with a semi-structured interview. Twenty professional footballers took part. The Immediate Anxiety Measurement Scale (IAMS) and Pressure Likert-type scale were administered prior to both conditions. The NeXus-10 biofeedback system recorded players' heart rate and respiration rate. Outfield players took five penalty kicks to four targets to the goal, under low and high-pressure. Pressure, cognitive anxiety, and respiration rate significantly increased in the high-pressure condition. After controlling for the level of pressure experienced in the high-pressure condition, bivariate variable error performance significantly increased (i.e., players were more variable in their grouping of shots under stress). Qualitative data indicated the 6-step high-pressure protocol predominantly evoked the distraction mechanism. This research provided first insight into the experiences of professional footballers to a simulated high-pressure penalty protocol. [ABSTRACT FROM AUTHOR]