Science & medicine in football最新文献

To explore the effects of Ramadan on proxy measures of match physical performance in professional Muslim football players competing in the Qatar Stars League using a three-phase interrupted time-series design. We examined total, high-speed running ( > 15 km·h^-1), very-high speed running ( > 20 km·h^-1), and sprinting ( > 25 km·h^-1) distances covered (m) by 45 professional Muslim football players tracked during official matches (322 individual measurements over 10 consecutive league rounds) and training (1168 individual observations) in periods preceding, during, and after Ramadan 1445. Separate multivariable-adjusted random-effects generalized additive models quantified the phase-specific effects of Ramadan on match running distances interpreted against the random match-to-match variability in total, high-speed running, very-high speed running, and sprinting distance of ± 494 m (95% confidence interval [CI], 480 to 508 m), ±200 m (95% CI, 195 to 206 m), ±102 m (95% CI, 99 to 105 m), and ± 60 m (95% CI, 58 to 61 m), respectively. Model-based phase-specific effects of Ramadan indicated mean reductions of 254 m (95% CI, 138 to 370 m) in total distance, 92 m (95%CI, 59 to 123 m) in high-speed running, and 31 m (95% CI, 12 to 50 m) in very high-speed running distance that were indistinguishable from random within-subject match-to-match variability. Effects for sprinting distance were inconsistent. Running distances covered during training were materially equivalent across study phases. In Muslim-majority environments like the State of Qatar, professional Muslim football players seem able to cope with Ramadan without experiencing substantial impairments in match physical performance or reductions in training load.

This study aimed at exploring the exposure of head impacts, i.e. headers and non-headers, in top-level female football players. The study included all teams (n = 10) and players (n = 238) in the Norwegian Women's Premier League during the 2023 season. Video analysis was used to register headers and non-headers in the 135 matches of the season. Potential head injuries were compared between video signs and medical reports. The header and non-header incidences were estimated per 90 match minutes with 95% confidence intervals (CI). We observed 9364 headers and 233 non-headers in 135 matches. Nine non-headers resulted in a head injury (all concussions), players' time loss ranging from 5 to 87 days. The highest number of headers performed by a single player in a match was 22. The total number of headers performed during a match varied between 34 and 125. Defenders had an estimated 4.2 (CI = 3.9-4.3), midfielders 2.9 (CI = 2.7-3.0), and forwards 2.6 (CI = 2.5-3.1) headers per match. There was a positive correlation between heading frequency and age. Forwards were the players most exposed to non-headers, with an estimated 0.09 per match. Most non-headers were caused by unintentional head-to-ball contact. We found that defenders had the highest header frequency. Header frequencies varied substantially between players and from match to match. Forwards had the highest risk of non-headers. Nine non-headers resulted in head injuries.

The objective of this observational cross-sectional study was to assess the knowledge, attitude and behaviour of coaches and performance staff (i.e. 'coaching staff'), and players from the 32 teams qualified for the FIFA Women's World Cup 2023 regarding assessment and management of concussion in football. Two online surveys were developed: 1) coaching staff, and 2) players. The results were analysed descriptively. Eighty-four coaching staff and 229 players completed the survey. Concussion knowledge: 39% of coaching staff and 33% of players were aware of concussion protocol(s). Knowledge: concussion symptom onset time was correctly reported by 18% of coaching staff and 11% of players. Knowledge about risks related to sustaining a concussion or returning to play too soon varied in both groups. Attitude: 26% of coaching staff and 31% of players reported being very confident or confident in recognizing a suspected concussion. Half of the players (52%) reported to always report symptoms of concussion if feeling any. One (1%) member of the coaching staff and 24 (10%) players reported feeling that a player can return to play with mild symptoms after a concussion. Behaviour: Most coaching staff reported they would have supportive behaviour if faced with a suspected concussion on the pitch. Among players, 64% stated that they would leave the assessment to their team's medical staff, and 4% would encourage their teammates to keep playing. In conclusion, coaching staff and players showed limited knowledge about concussion. Most coaching staff reported attitudes and intended behaviour towards protecting players' health; whilst players' responses varied.

Rule changes within football-code team sports aim to improve performance, enhance player welfare, increase competitiveness, and provide player development opportunities. This manuscript aimed to review research investigating the effects of rule changes in football-code team sports. A systematic search of electronic databases (PubMed, ScienceDirect, CINAHL, MEDLINE, and SPORTDiscus) was performed to August 2023; keywords related to rule changes, football-code team sports, and activity type. Studies were excluded if they failed to investigate a football-code team sport, did not quantify the change of rule, or were review articles. Forty-six studies met the eligibility criteria. Four different football codes were reported: Australian rules football (n = 4), rugby league (n = 6), rugby union (n = 16), soccer (n = 20). The most common category was physical performance and match-play characteristics (n = 22). Evidence appears at a high risk of bias partly due to the quasi-experimental nature of included studies, which are inherently non-randomised, but also due to the lack of control for confounding factors within most studies included. Rule changes can result in unintended consequences to performance (e.g., longer breaks in play) and effect player behaviour (i.e., reduce tackler height in rugby) but might not achieve desired outcome (i.e., unchanged concussion incidence). Coaches and governing bodies should regularly and systematically investigate the effects of rule changes to understand their influence on performance and injury risk. It is imperative that future studies analysing rule changes within football codes account for confounding factors by implementing suitable study designs and statistical analysis techniques.

Academy soccer coaches evaluate players' skilfulness to inform talent identification and development, focusing on technical proficiency, adaptability, decision-making, and influence. However, limited research has explored coaches' perceptions of skilfulness after completing an assessment. Furthermore, little is known about the potential overlap between current skill performance and future potential, or how coaches consider the skilfulness sub-dimensions. This mixed methods study explored how experienced Australian male youth soccer coaches (n = 5) and academy directors (n = 10) (M_age = 42.5 ± 13.8 years; M_experience = 19.2 ± 9.8 years) rated players' skill performance and potential, their emphasis on sub-dimensions, and perceptions of evaluating them. Participants completed an online survey with pre-recorded small-sided game videos. Quantitatively, they rated players' skill performance and potential and emphasis on each sub-dimension using five-point Likert scales. Qualitatively, they responded to open-ended questions. Quantitative data were analysed using Spearman Rank Correlations and a Wilcoxon Signed Rank Test. Qualitative responses were explored via content analysis. Coaches' ratings were partially supported by their reflections on evaluating skill, as they reported feeling competent in rating players' skill performance but required more information on players' backgrounds to assess potential. Given a high overall correlation between coaches' ratings of skill performance and potential (r = 0.79, p =  < .001), coaches may have inferred potential from players' performance, possibly explaining their desire for contextual information. While all sub-dimensions were rated as equally important for performance and potential, coaches described using unique criteria for each, highlighting the need for distinct information from skill assessments.

This study aims to examine and describe the characteristics of potential injury situations during a men's professional international tournament quantified using the FIFA Football Language Medical Coding. A prospective study was conducted during the 64 matches of the FIFA World Cup Qatar 2022™, during which five analysts recorded potential injury situations from video analysis. "Potential injuries" were recorded when players stayed down > 5 s and/or requested medical attention. Characteristics were further recorded for variables such as opponent's action and body location. In total, 720 potential injury situations were recorded of which 139 required medical assessment. The actions which resulted in most potential injuries were running while receiving a pass (74; 10%), while passing the ball (59; 8%), and while progressing with the ball (48; 7%). Duels and ball progression led to a potential injury in 3.0% and 2.1% of all similar actions in total. Both aerial duels and ball progression led to an potential injury that required medical assessment on 0.4% of occasions. Most potential injuries involved the head (149; 21%), foot (120; 17%), or lower leg (110; 15%) with most medical assessments of the head (35; 25%), lower leg (17; 12%), and knee (15; 11%) with a median duration of 47 seconds (IQR 28-61). This study provides a detailed overview of match circumstances that may have a higher injury risk. Although some variables within the coding system need improvement to increase reliability, its use will allow a more detailed comparison of differences between high-risk player actions leading to injury and those that do not, which can improve future prevention strategies.

Objectives: The study investigated the locomotor and tackle pacing profile and loads of female rugby league players following various between-match turnaround durations. Specifically, the study examined the (1) pacing of locomotor and tackle loads across the time-course of a match and; (2) whole-match and peak locomotor and tackle loads of match-play.

Methods: Microtechnology data were collected from elite female rugby league players (n = 172) representing all National Rugby League Women's teams (n = 6 teams) across two seasons. Players were categorised into backs, adjustables, forwards or interchange players. Data was calculated for the whole-match (m), per minute (m.min^-1) and peak (running: m.min^-1; acceleration: m.s^-2) locomotor and tackle loads (number and efficiency (%)) of match-play. The pacing as well as the locomotor and tackle loads of match-play were examined following short (≤6 days), normal (7 days) or long (≥8 days) turnarounds.

Results: The pacing profile of playing positions varied across short, normal and long match turnarounds. Trivial to moderate differences existed in the whole-match, per minute and peak locomotor loads across match turnaround durations (effect size ≤ 1.2).

Conclusions: Following various between-match turnaround durations (i.e., short, normal and long match turnarounds), there were variations in the locomotor and tackle pacing profile and loads whereby, the pacing profile of positional groups was more affected than the load profile. The findings can be used in applied settings to guide the recovery strategies and training plans of female rugby league players to optimise performance and wellbeing across various match turnaround durations.

Football carries a high risk of injury for youth players. The aim of this study was to investigate the epidemiology of football-related injuries in young male players. The data stems from a previously conducted cluster-randomised controlled trial that investigated the efficacy of 'FUNBALL', a new injury prevention programme. This study contains the data of the 503 players of the control arm. The players belonged to 22 football teams of the Under-(U)15, U17 and U19 age groups. The time-loss injuries were recorded during the season 2021-2022 according to the Football Consensus Statement. An analysis on the injury incidence (IR, calculated per 1000 hours of exposure), location, severity, category, and type was performed. Incidence rate ratios (IRRs) were used to compare the variables between the specific age groups. 187 injuries (96 in training and 91 in matches) occurred during 52 938 hours of exposure. The overall IR was 3.53 injuries/1000 h (95% confidence intervals (CI) 3.06 to 4.07). The training IR was 2.16 injuries/1000 h (95% CI 1.17 to 2.64). The match IR was 10.50 injuries/1000 h (95% CI 8.55 to 12.89). In the U19s, the overall IRR was higher compared to the U17s (IRR 1.57, CI 1.12 to 2.19; p = 0.008) and compared to the U15s (IRR 1.82, 95% CI 1.25 to 2.62; p = 0.001). The thigh was the most commonly affected body region (IR 0.92/1000 h, 95% CI 0.69 to 1.22). Muscle injuries were the most common injury type (IR 1.05/1000 h, 95% CI 0.81 to 1.37). Injury burden was 74 lost days/1000 h. The findings of this study indicate a lower injury incidence in youth players than in adult ones. We observed a higher injury incidence towards the older age groups.

The objective of this observational cross-sectional study was to assess the knowledge, attitudes and behaviours of medical staff participating in the FIFA Women's World Cup 2023 regarding the assessment and management of concussion in football. Medical staff from 32 teams qualified for the FIFA Women's World Cup 2023 were invited to answer an online survey. Results were analysed descriptively. 47 participants completed the survey. Concussion knowledge: 98% were aware of concussion protocol(s). Most concussive signs or symptoms were recognised, though only 36% of participants (n = 17) correctly reported potential symptom onset time. Knowledge on assessment and return to play elements varied. Attitude: 77% (n = 36) reported being very confident or confident in recognizing a suspected concussion. When assessing a suspected concussion on the pitch, 55% (n = 26) reported to have felt pressured by the player sometimes, very often or always, and 47% (n = 22) by the coaching staff. Behaviour: Among doctors, 70% reported their national team performs baseline concussion assessments. Reported use of on-field assessment elements suggested in concussion guidelines varied between 5% and 95%. In conclusion, most medical staff participating in the FIFA Women's World Cup 2023 were generally knowledgeable about concussion, reported on-pitch and return to play attitudes and behaviours aligning with evidence-based standards for safeguarding players' health. However, gaps were observed in all three domains, compared to guidelines. Expanding education to players and coaching staff is suggested to facilitate the delivery of evidence-based best practice.

Objectives and methods: This study aimed to examine whether biological maturation and relative age selection biases existed and varied by level of competition (regional, national, and international) in Under-15 soccer players (n = 951) within the Swedish Football Association's male player pathway. A secondary aim was to examine the relationship between relative age and body height, body weight, predicted adult height, percentage of predicted adult height (PAH%), maturity Z-score, and biological age to chronological age offset.

Results: The results showed a significant bias (p < 0.001), ranging from trivial-to-small in favour of relatively older players, with the most notable increase between the regional and national levels. There were also significant moderate-to-large biases in favour of early maturing players (p < 0.001), increasing in magnitude with levels of competition. PAH% (p < 0.001) and body weight (p = 0.014) showed the strongest differences across selection levels, where the bias compared to regional level was 0.23 standard deviations (SD) for PAH% at national level and 0.41 SD at international level, while body weight appeared to be particularly related to international team selection (0.36 SD in bias). Relative age showed a moderate positive correlation with PAH% (r = 0.38), but only trivial correlations with all the other biological and physical variables examined (r=-0.05-0.11).

Conclusions: The lack of association between relative age and the estimates of biological maturity timing and the additional physical characteristics suggests that relative age and biological maturity are distinct constructs. We encourage critical examination of how associations select young players for national talent programmes; current practices significantly diminish the chances of selection for those who are late maturing and relatively younger.