Identifying talented young soccer players is key to establishing the success of professional soccer clubs but is challenging and contains inherent risk. This paper suggests that adopting an interdisciplinary approach using disciplines outside of sport science will reveal a significant amount of pertinent research and knowledge that has yet to be applied to soccer. This is illuminated by the argument that modern biological anthropology frameworks and data, in particular, have the potential to enhance current practice and address gaps in knowledge and understanding. Using the example of biological maturation assessment, the paper demonstrates the limitations of the current methods used in sports science, the contribution that modern biological anthropology has made to our understanding of biological maturation and provides an agenda for future work through a more nuanced multidisciplinary approach.

Travel poses a significant logistical challenge to elite North American soccer. We explored how medical and performance practitioners perceive its impact on player performance and recovery. Thirteen practitioners first completed a pre-survey to define 'travel' in this context. A main survey followed, involving 44 practitioners, assessing perceptions of travel-related factors such as travel duration, logistics, arrival and departure times, time-zone changes, and mitigation strategies. The survey included yes/no, Likert scale, and open-text questions. Impact was rated on a seven-point Likert scale from large negative (1) to large positive (7), with ±0.5 points from the 'no impact' midpoint (4) considered substantial. High internal consistency was observed for questions on overall impact, travel duration, and time-zone differences (Cronbach's alpha 0.97 to 0.98) and mean ratings subsequently calculated for each item. Open-text responses were analyzed thematically, informed by interpretive analysis. Practitioners perceived negative impact on performance and recovery (second‑generation p‑value = 0, with 95% confidence intervals entirely outside our ±0.5‑point practical relevance zone). Most reported that cumulative travel, during congested fixture periods (98, 95% confidence intervals, 88 to 100%) and across a full season (91, 79 to 96%), had further negative impact. When travelling prior to the match practitioners clearly preferred arriving before 5 pm on matchday and returning after an overnight stay. A recurring theme in qualitative responses was the importance of minimizing disruptions to daily routines, particularly sleep. These findings highlight the need to understand the cumulative impact of travel, particularly the roles of late-night arrivals, extended journeys, and sleep disruption.

Our study investigated the effects of a six-week jump-training intervention (sand- vs land- based incorporated in a warmup), on frontal plane knee angle and jump performance of adolescent female football players. Fifty-six females were randomly allocated to either the SAND or LAND group. Thirty-nine females completed the programme twice weekly and were eligible for analysis. Two-dimensional frontal plane projection angle (FPPA), countermovement jump (CMJ) and reactive strength index (RSI) (10-5 repeated jump test) were measured 1-week pre- and post-intervention. Analysis of covariance was used to model post-intervention group differences. Compatibility curves were used to visualise parameter estimates alongside p- values, and surprisal (S) value transforms. Mean difference (X) and compatibility intervals (CI) (95|75%) for FPPA for SAND vs. LAND were X = 1.29 degrees (-0.11 to 2.69 degrees|0.49 to 2.10 degrees) for the dominant limb, and X = 1.80 degrees (0.56 to 3.04 degrees|1.09 to 2.51 degrees)| for the non-dominant limb. Interval estimates for jump performance were imprecise and unclear. The data indicates that including a sand surface within a jump training intervention could be beneficial when aiming to improve knee control in asymptomatic adolescent female football players, with no apparent detriment to jumping performance. Clinical trials registration: The trial was registered with clinicaltrials.gov prior to study recruitment (NCT04502615).

This study analyzed the longitudinal relationship between short sprints and counter movement jump (CMJ) in youth male soccer players. Players (n = 304, age 13.0 ± 1.9 years) from a Scottish soccer academy completed sprints (10 m, 20 m splits [s]) and a CMJ (cm), on 3 to 14 occasions across 10 seasons. Within-player (repeated measures) and between-player (mean of repeated measures) correlation coefficients were calculated, and a linear mixed model (LMM) was applied to determine whether CMJ can predict sprint changes over a meaningful threshold (0.04 s, equivalent to the suggested minimum difference [~40 cm] for a player to be ahead of the opponent to win a ball in a one-on-one duel). Very large, negative between-player correlations were found for CMJ vs. sprint time (10 m: r = -0.746, 95% CI [-0.792, -0.691]; 20 m: r = -0.822, 95% CI [-0.856, -0.782], respectively). Within-player correlations were moderate-to-large (10 m: r = -0.485, 95% CI [-0.525, -0.443]; 20 m: r = -0.576, 95% CI [-0.611, -0.539]). The LMM analysis revealed that chronological age influenced the within-player correlations, while CMJ did not predict sprint changes over the meaningful threshold. While CMJ might be useful for distinguishing between players with differing sprint ability, it is not a suitable proxy for tracking individual sprint development over time, especially when accounting for chronological age-related changes. Coaches and practitioners should therefore consider incorporating direct sprint assessments into longitudinal monitoring.

This study explores the structural challenges facing grassroots boxing clubs in their pursuit of long-term sustainability, with a focus on how club leaders navigate the intersection of community leisure provision, economic precarity, and institutional demands. Drawing on semi-structured online interviews with 12 club leaders across England, the research offers insight into the lived realities of sustaining boxing as a form of accessible, community-based leisure. By applying Bourdieu's framework, the study identifies three interrelated thematic pressures: (1) precarity as a normalised practice, (2) capital conversion and institutional misrecognition, and (3) symbolic domination and governance disconnect. Through this lens, the analysis reveals how club leaders contend with both material constraints and symbolic struggles for recognition, legitimacy, and autonomy. The findings suggest that sustainability in grassroots boxing is not simply a matter of finance, but of navigating a field structured by unequal distributions of capital, institutional power, and cultural legitimacy. The study calls for more inclusive governance and funding mechanisms that recognise the embedded knowledge, labour, and community value of grassroots sport.

Isometric knee-flexor testing is commonplace in soccer, yet data to inform choice of knee-flexion angle are limited. This study aimed to compare peak force production and muscle activation between two isometric knee-flexor tests. To compare peak force, 43 male soccer players (age 21.5 ± 5 years; stature 180.3 ± 6.3 cm; body mass 74.6 ± 8.9 kg) completed 3 × 5-second maximal efforts on the Nordbord device (Vald Performance) with a 0- (ISO-Prone) and 30-degree (ISO-30) knee angle, respectively. To compare peak muscle activation, a further 13 trained male participants (25 ± 6 years; 178.2 ± 5.6 cm; 79.6 ± 13.2 kg) completed 3 × 5-second maximal efforts with wireless surface electromyography electrodes placed on the Gluteus Maximus, Adductor Magnus, Semitendinosus, Biceps Femoris (long and short heads) and Medial Gastrocnemius. Paired samples t-tests were used to detect differences in force output between tests and Pearson's correlations to quantify associations. A Yuen's modified t-test estimated the trimmed mean differences in muscle activation between tests. Higher peak forces were observed in the ISO-30, with mean differences of 56.4N (36.8 to 75.9 [95% CI]) and 52.9N (33.7 to 72.3 [95% CI]) for right (367 vs 314N) and left legs (351 vs 294N), respectively. Moderate correlations were observed in peak force for left (r = 0.55 (0.29 to 0.73 [95%CI])) and right (r = 0.64 (0.42 to 0.79 [95%CI]) legs. No differences in muscle activation were observed. Peak force varies between the ISO-Prone and ISO-30, with moderate associations between tests, indicating that the tests should not be used interchangeably.

Background Physical activity, aerobic and resistance training have established benefits to health and wellbeing, with physiotherapists playing a vital role in their promotion. Objectives To capture UK student and graduate physiotherapists (1) knowledge of accepted guidelines and, (2) perceptions of physical activity and exercise prescription in practice. Design National cross-sectional online survey. Methodology A survey was conducted online among UK student and graduate physiotherapists from July to December 2021. Quantitative questions included dichotomous (yes/no), multiple-choice, and Likert scale (1-5) formats, alongside open-ended qualitative questions. Results Of 305 respondents (18% students, 47% >10 years’ experience), 295 (97%) either “agreed” (n = 64, 21%) or “strongly agreed” (n = 231, 76%) that physical activity was a part of their role. Less than half felt the physiotherapy profession was able to provide effective physical activity (n=149, 49%, 95% confidence intervals 43 to 54) and aerobic training (130, 43%, 37 to 48). Most knew the weekly minimum adult dosage of physical activity (257, 84%, 80 to 88) and resistance training (267, 88%, 83 to 91) but were generally unable to correctly identify aerobic and resistance training guidelines. Of those who used evidenced based guidelines regularly with patients 72% were not adopting correct guidelines for aerobic (n= 58, 72%, 61 to 80) and 46% for resistance training (n=45, 46%, 36 to 56). Limited patient appointment duration, inadequate access to facilities and a lack of continuous professional development opportunities were perceived barriers to implementation. Conclusion Respondents agreed physical activity and exercise are vital treatment modalities, however many lack the knowledge to deliver these interventions in line with contemporary guidelines.

Purpose: Travel fatigue impacts cognitive and physiologic systems, but its association with elite soccer match performance is unclear. In this retrospective observational study, we aimed to explore the association between travel and match outcomes in elite North American soccer. Methods: Travel data and match outcomes (team points or goals scored and conceded) and physical performance outcomes from 26 elite professional soccer teams and their players were analyzed (148 matches [team-based data] and 1252 player matches from 297 players; age 22.7 [4.5] y). Player- and match-level correlations between performance measures and both acute and cumulated travel metrics were analyzed. Results: Cumulative travel metrics were positively associated with team (travel distance [r = .20; 95% CI, .03–.25], travel time [r = .20; .06–.37], and time away [r = .20; .06–.37]) and individual player (travel distance, [r = .14; .08–.19], travel time [r = .17–.23], and time away [r = .13; .07–.18]) high-intensity running. Cumulative time away was negatively associated with team points (r = −.14; −.28 to −.001) and positively associated with goals conceded (r = .14; .01–.27); no clear association between acute travel metrics and match outcomes or physical performance was observed. Conclusions: As travel cumulated, away teams and their players ran more but for less reward (team points), although the magnitude of these associations was small. These data are exploratory and do not imply a causal relationship; however, further research should consider cumulation of travel.

Despite interest in multi-sports training as a strategy to enhance long-term player development in soccer, current practice within English professional soccer academies is not well understood. This study explored the use of multi-sports training by English professional soccer academies (i.e., if multi-sports training was used, how often, session duration, activity type and age-group variations), and practitioners’ perspectives with respect to player development (i.e., perceived physical/sociological benefits of; and barriers to use) using an online survey. One practitioner per club, per age category (i.e., Foundation (<9 to <12 years), Youth (<13 to <16 years) and Professional (<18 to <23 years)) was permitted to respond. Sixty practitioners responded, of which, 48% worked with U18-U23 players; 42% with U13–14 and U15–16 players, respectively; 20% with U9–10 players and 33% with U11–12 players. Half ( n = 30) of the respondents used multi-sports training for a total of 1 (IQR 1–2) session and 30 (13 to 60) minutes per week. Respondents ‘agreed’ or ‘strongly agreed’ that multi-sports training improved physical outcomes, reduced injury risk, helped to avoid early professionalism, and improved communication and problem-solving. Several barriers to inclusion were identified, such as limited training time, lack of equipment and attrition from other staff and players. In summary, although multi-sports training was used by only ∼50% of practitioners, indicating that many clubs specialise in deliberate soccer practice, most practitioners perceived multi-sports training to be beneficial to player development.

OBJECTIVE:To evaluate non-contact injury prevention strategies of professional men's soccer clubs in elite North American league soccer. To understand the application, perceived effectiveness and barriers to implementation. DESIGN:Online cross-Sectional Study. SETTING:North American elite soccer teams. PARTICIPANTS:96 medical and performance support staff of elite North American teams. MAIN OUTCOME MEASURE:The survey consisted of 20 questions and captured 1) practitioners' demographics; 2) perceptions of risk factors; 3) the use of assessment and monitoring strategies; and 4) perceptions of the implementation of injury prevention programmes'. RESULTS:Injury prevention programmes were perceived as 'effective' (Median 4, Interquartile range 4-4) and reduced injury rates (n = 94, 98%, 95 CI% 93 to 99). A range of potential risk factors were rated as "very important" (4.58 ± 0.52 Likert scale points; mean ± standard deviation). A multi-disciplinary approach to the design, application and monitoring of programmes was generally adopted. Competing training priorities (n = 75, 78%, 95 CI% 69 to 85) and game schedules (n = 71, 74%, 95 CI% 64 to 82) were the most prevalent barriers to injury prevention implementation. CONCLUSIONS:Injury prevention programmes were perceived as effective in reducing non-contact injuries. Managing the conflicting priorities between scheduling training, tactical and conditioning goals were considered the key barriers to desired implementation.

ABSTRACT Authentic practical assessment is a critical examination strategy in healthcare courses. The key aims of this article were to (a) investigate students’ ability to predict their awarded grade, (b) understand students’ satisfaction with the marks awarded, and (c) identify students’ perception of assessment fairness. Students on a preregistration healthcare course (n = 124) from Levels 4 to 6 were surveyed via an online questionnaire. Students were asked to grade their own examination, questioned if their mark met their expectation, and consider if they felt their mark was fair. Students were asked to quantify any differences between perceived and actual grades in percentage points. Results suggest students at Level 4 display greater accuracy of calibration. Satisfaction of marks was high across all levels, as was perceived fairness of grades. Additional focus on assessment literacy in authentic practical examinations may be required to support students to understand the experiential changes to marking criteria.

AIMS:The physiologic challenges related to performances in hot conditions calls for dedicated consideration when planning athlete training, although complete amelioration of the effects of heat may not be possible. We aimed to quantify within-subject correlations between different measures of environmental temperature and performance changes over multiple elite soccer competitions. METHODS:Thirty-seven elite male soccer players (age: 26 ± 3.4 years, height: 171 ± 2 cm, body mass: 78 ± 7.1 kg) competed in North America over four seasons (range: 3 to 98 matches). Players wore global positioning system devices during games and reported differential-RPE immediately post game. Temperatures at kick-off, week average temperature, the difference between game-day and week average (DiffTemp), and heat index at kick-off were obtained. Within-player correlations were calculated using general linear models to quantify associations between fluctuations in temperature measures and physical and perceived outputs. RESULTS:Correlations between total distance and the various temperature measures were trivial to small (range: -0.08 to 0.13, p=<0.001-0.02). Small negative correlations were found between all temperature measures except DiffTemp and high-speed running (HSR) (range: -0.17 to -0.14, p=<0.001). Most correlations between differential-RPE and temperature measures were trivial to small and not significant (r = 0.06 to 0.18 p = 0.03-0.92) although breathlessness-RPE and heat index showed a small significant association (P = 0.018). CONCLUSION:Decrements in HSR appear to be associated with increased environmental temperature, however, these associations are small in magnitude.

This study analysed the longitudinal relationship between short sprint time and the leapfor-distance test using novel motion tracking in young soccer players.Players (n = 144, age 14.8 ± 1.8 years) from six English Elite Player Performance Plan category three clubs completed two linear sprints (10 m, 20 m) and a leap-for-distance test (cm), on three to seven occasions across three seasons.Within-player (repeated measures) and betweenplayer (mean of the repeated measures) correlation coefficients were calculated and stratified by pre-and post-peak height velocity (PHV).Very large, negative between-player correlations were found for leap-for-distance vs. sprint time (10 m: r = -0.70,95% CI [-0.77, -0.61]; 20 m: r = -0.77,95% CI [-0.83, -0.70]).Correlations were large for pre-PHV (10 m: r = -0.52,95% CI [-0.71, -0.26]; 20 m: r = -0.62,95% CI [-0.78, -0.39]) and moderate-to-large for post-PHV (10 m: r = -0.43,95% CI [-0.60, -0.24]; 20 m: r = -0.54,95% CI [-0.68, -0.36], respectively).Within-player correlations were trivial-to-small for all players (10 m: r = -0.14, 95% CI [-0.24, -0.06]; 20 m: r = -0.24,95% CI [-0.34, -0.16]) and for pre-and post-PHV subgroups (r's < -0.30).Leap-for-distance is a useful discriminator of sprint performance but should not be used for tracking intra-player sprint changes in young soccer players, irrespective of maturation.

ABSTRACT Ishida, A, Draper, G, Wright, M, Emerson, J, and Stone, MH. Training volume and high-speed loads vary within microcycle in elite North American soccer players. J Strength Cond Res 37(11): 2229-2234, 2023-The purposes of this study were to reduce dimensionality of external training load variables and examine how the selected variables varied within microcycle in elite North American soccer players. Data were collected from 18 players during 2018-2020 in-seasons. Microcycle was categorized as 1, 2, 3, 4, 5 days before match day (MD-1, MD-2, MD-3, MD-4, and MD-5, respectively). Training load variables included total distance, average speed, maximum velocity, high-speed running distance (HSR), average HSR, HSR efforts, average HSR efforts, sprint distance, average sprint distance, sprint efforts, average sprint efforts, total PlayerLoad, and average PlayerLoad. The first principal component (PC) can explain 66.0% of the variances and be represented by "high-speed load" (e.g., HSR and sprint-related variables) with the second PC relating to "volume" (e.g., total distance and PlayerLoad) accounting for 17.9% of the variance. Average sprint distance and total distance were selected for further analysis. Average sprint distance was significantly higher at MD-3 than at MD-2 (p = 0.01, mean difference = 0.36 m•minute-1, 95% confidence intervals [CIs] = 0.07-0.65 m•minute-1) and MD-4 (p = 0.012, mean difference = 0.26 m•minute-1, 95% CIs = 0.10-0.41 m•minute-1). Total distance was significantly higher at MD-3 than at MD-1 (p < 0.001, mean difference = 1,465 m, 95% CIs = 1,003-1926 m), and MD-2 (p < 0.001, mean difference = 941 m, 95% CIs = 523-1,360 m). Principal component analysis may simplify reporting process of external training loads. Practitioners may need to choose "volume" and "high-speed load" variables. Elite North American Soccer players may accumulate higher average sprint distance at MD-3 than at other training days.

ABSTRACT Soccer match play dictates that players possess well-rounded physical capacities. Therefore, player physical development plans must consider developing several fitness components simultaneously. Effective individualization of training is likely facilitated with appropriate player profiling; therefore, developing a time-efficient and informative testing battery is highly relevant for practitioners. Advances in knowledge and technology over the past decade have resulted in refinements of the testing practices used by practitioners working in professional male and female soccer. Consequently, a contemporary approach to test selection and data analysis has progressively been adopted. Furthermore, the traditional approach of using a testing battery in a single day may now be outdated for full-time players, with a flexible approach to the scheduling of testing perhaps more suitable and time efficient. Here, guidance on testing for maximal aerobic, submaximal aerobic, linear and change of direction speed, and stretch-shortening cycle performance (i.e., jump testing) are presented for male and female players, with emphasis on time-efficient tests, while facilitating effective individualized training prescription. Normative and meaningful change data are presented to aid decision making and provide a reference point for practitioners. Finally, a time-efficient approach to scheduling fitness testing is presented, which complements daily training outcomes of a weekly periodization approach.

Using Brofenbrenner's socio-ecological model as a conceptual framework, the objective of this study was to determine playground users (primary school staff and pupils) perceptions of the barriers and facilitators to a physically active school playground at an intra-personal (individual), inter-personal (social), environmental and policy level. Results from a series of qualitative interactions with children (n = 65) from years five and six (9 to 11 years old), and structured interviews with adult teachers (n = 11) revealed key differences in the child and adult perceptions of the playground and the purpose of break-times. A number of inter-related environmental boundaries and school policies were identified as restrictive to children's explorations and activity levels during 'free play' periods, which centred on resource availability, accessibility and health and safety. Further, traditional playground hierarchies act to promote and prevent physical activity engagement for different groups (e.g. gender and age). Finally, differences between the adult and child perception of the primary school playground were observed. Playground physical activity, during break-times appears to be affected by a number of variables at each level of the socio-ecological model. This study provides an opportunity for primary schools to reflect on primary school playground strategies and practices that are implemented at each level of the socio-ecological model to encourage a more effective use of the playground during school break-times.

Players involved in the various football codes compete throughout the calendar year around the world. Therefore, environmental stressors such as temperature and altitude should be considered in preparation for, and during, matches. We aimed to systematically review the observational and quasi-experimental studies that have been specifically designed to quantify the effects of temperature (hot or cold) high altitude on in-match physical performance indicators. A search of electronic databases (Web of Science, Scopus, SPORTDiscus, PubMed/MEDLINE) was conducted, with 19,424 papers identified as relevant. Following sifting in relation to the eligibility criteria, 12 papers were deemed directly relevant. The reviewed studies scored 6-9 (on a 0-9 scale) for quality assessment using a previously used scale. The major outcome variables relevant to the current review were total distance (m), high-speed running (m) and high-speed runs (count) measured during matches. Standardized effect sizes (ES) were heterogeneous across studies for total distance (ES: -0.96 to -0.14) and high-speed running (ES: -0.69 to 0.12) for >1000 m vs sea-level, time spent at the given altitude being a putative factor for this heterogeneity. Heat had mainly detrimental effects on performance, but ES were, again, heterogeneous across studies (ES: -1.25 to 0.26), dependent on temperature. Given the small number of studies that involved mostly male athletes, and large heterogeneity across studies, more research needs be conducted on physical performance in these environmental conditions, with attention paid to standardizing outcomes and broadening the approaches of studies to guide future decision-making in professional sporting environments.

Fundamental movement skill (FMS) competence is associated with physical activity during childhood, with higher FMS competence associated with higher physical activity levels; however, the effectiveness of FMS interventions in primary school-aged children is not fully understood. The purpose of this study was to evaluate the effectiveness of FMS interventions at improving daily levels of moderate to vigorous physical activity (MVPA) in 5- to 11-year-old children. Systematic searches were completed in eight electronic databases (MEDLINE, CINAHL, PubMed, Web of Science, SPORTDiscus, EMBASE, ERIC and Scopus). Studies were included if they were randomised or non-randomised controlled trials that implemented a physical activity intervention with an FMS component in 5- to 11-year-old children and included objectively measured daily levels of MVPA. Methodological quality was assessed using the Cochrane risk of bias tools for randomised and non-randomised controlled trials. Random effects meta-analysis was performed to determine the pooled intervention effect (mean difference) on minutes spent in MVPA with meta-regression for the use of an operationalised definition of FMS, in line with the criteria reported by Logan et al. A total of 19 studies were identified for review and 14 studies were eligible for meta-analysis. The pooled intervention effect was 4.3 min (95% confidence interval [CI] − 0.03 to 8.8) of MVPA per day. The percentage of future studies likely to find an effect greater than the minimal clinically important difference was 47% (95% CI 22–70). Studies that attempted to conceptualise and define FMS by combining at least one of Logan and colleagues’ operational definitions with a measure of FMS had a positive effect on daily MVPA (13.3 min/day, 95% CI 8.0–18.6; R2 = 0.89). Meta-regression for the three levels of criteria reported by Logan et al. showed a linear increase in MVPA, with studies using all three criteria experiencing the largest additive effect (15.7 min/day, 95% CI 8.9–22.6; R2 = 0.89). FMS interventions have the potential to increase daily levels of MVPA in 5- to 11-year-old children. However, future studies should concentrate on establishing an accurate conceptualisation of FMS and how FMS will be integrated within their intervention to further increase physical activity levels. Prospero registration number: CRD42017058718.

The school playground can promote PA for large numbers of children. This study identifies areas of the playground that children visited at break-times, the decisions according to gender and the influence of contextual and environmental variables on PA levels. The playground of a culturally diverse primary school was observed during morning break-times and lunchtimes. Counts of sedentary, LPA, and MVPA episodes, and the contexts in which they occurred were recorded using the system for observing play and leisure in youth (SOPLAY). Ball sports areas had higher counts of boys (mean ± SD; 9.9 ± 4.8) compared to girls (2.0 ± 3.5); areas promoting climbing and social interaction had higher counts of girls (7.9 ± 7.2) compared to boys (3.5 ± 2.9). The proportion of MVPA episodes during break-times was 34% ± 26%. Areas of the playground with organised activities had 2.70 (95%CI: 1.87 to 3.91) times higher MVPA counts than areas "not organised". Areas with "supervision" were associated with higher MVPA counts (1.34; 1.18 to 1.53) compared with "not supervised" areas. Organisation and supervision might influence PA choices and PA levels of children in the primary school playground. Further investigation is required to explore different playgrounds settings, and context and gender preferences.