Risk factors for hamstring muscle injury in male elite football: medical expert experience and conclusions from 15 European Champions League clubs

Development of a preliminary multivariable model predicting hamstring strain injuries during preseason screening in soccer players: a multidisciplinary approach

OBJECTIVE

Reducing the incidence of hamstring strain injuries (HSIs) is a priority for soccer clubs. However, robust multifactorial predictive models are lacking and potential predictors such as sprint kinematics, performance fatigability, and psychological variables have been overlooked. Thus, the aim of this study was to develop a preliminary parsimonious multifactorial model to predict players at risk of HSI through preseason screening.

MATERIALS AND METHOD

Psychological, physiological, kinematic, performance fatigability and health-related variables were collected for 120 regional and national soccer players during the 2022 preseason. HSIs were prospectively recorded over the entire soccer season. After variable selection, logistic regressions with the Wald backward stepwise method were used to refine the model. The predictive abilities of the model and of the individual variables were determined using the area under the receiver operating characteristic curve (AUC).

RESULTS

Twenty-nine players sustained an HSI during the follow-up period. The final model included eight variables: age, sex, HSI history, knee flexor performance fatigability, sprint performance (best sprint time and maximal theoretical velocity V0), perceived vulnerability to injury, and subjective norms in soccer. While its model was preliminary, it showed good fit indices and strong predictive performance (true positive rate: 79%, AUC = .82). None of the variables evaluated independently demonstrated satisfactory performance in predicting HSI (AUC≤.65).

CONCLUSION

Using a multidisciplinary approach and measurements of only a few variables during preseason screening, the current model tends to demonstrate high accuracy in identifying soccer players at risk of HSI.

Training-Related Sports Injury Patterns Among Elite Middle and High School Field Hockey Players in Korea

This study aimed to analyze the incidence, affected areas, and types of injuries sustained during training among youth field hockey players to identify key characteristics. A survey was conducted with 374 youth field hockey players (236 males, 138 females) from middle and high school teams registered with the Korea Hockey Association in 2024. Data were collected on injury status, training hours, injury sites, and prevention methods. Chi-square tests, independent t-tests, and frequency analyses were performed to assess differences in injury incidence based on gender and school level. The analysis revealed no significant gender differences in training-related injury experiences, with 17.2% of male athletes and 10.2% of female athletes reporting injuries during training. Similarly, no significant difference was found between middle and high school athletes, although high school athletes had a significantly lower injury incidence than middle school athletes (1.54 vs. 2.28 per 1000 h, p < 0.05). The most common injury sites were the ankle and knee, with muscle injuries being the most frequent among males and ligament injuries among females. Additionally, male and high school athletes more frequently reported engaging in warm-up and cool-down exercises. There was no significant difference in injury rates between genders during training, but high school athletes tended to experience fewer injuries than middle school athletes. Ankle injuries were the most common, with muscle and ligament damage being the primary types of injuries. While warm-up exercises were commonly practiced, further research is needed to determine their actual effectiveness in injury prevention.

Neuromuscular fatigue in English Premier League academy football players: Within- and cross-season responses

OBJECTIVES

To examine the within- and cross-season neuromuscular fatigue responses in English Premier League U-18 academy football players.

DESIGN

Twenty-five players from the same team completed weekly countermovement jump and isometric adductor and posterior chain strength tests for a full competitive season.

METHODS

Global positioning system measures of training and match total, high-metabolic load and sprint distance were recorded daily and converted into exponentially weighted moving average seven- and twenty-eight-day values.

RESULTS

TD28 (p < .001), HML28 (p < .001), and SD28 (p = .002) shared negative relationships with countermovement jump height, but there was no main cross-season effect (p = .137). TD28 (p = .016) and HML28 (p = .012) positively related to isometric posterior chain strength but there was no effect of SD28 (p = .653), SD7 (p = .549), TD7 (p = .080) or HML7 (p = .104). Cross season, isometric posterior chain strength followed a curvilinear response whereby performance increased across the beginning of the season and decreased towards the end of the season (p = .003). There was no effect of training load or time on isometric adductor strength performance (p > .094).

CONCLUSIONS

Neuromuscular status, signalled by countermovement jump height changes fluctuates across the season in response to sustained changes in training and match load, but there is no evidence of a main cross-season linear effect. Total training and match volume exert moderating effects on the internal training load dose, and in-turn, important moderating effects on neuromuscular fatigue, particularly when composed of high volumes of high-intensity and sprint distances. The posterior chain might be particularly susceptible to fatigue towards the end of the season.

'Good communication and good team building, it's half of the work in managing a player': how team doctors perceive communication in the European professional men's football context

Communication influences players' performance and health and is influenced by the leadership style of coaches, internal team communication and the integration of the medical team in the professional men's football setting. However, the communication process between medical teams and other stakeholders in professional football has not been described in depth. Therefore, we explored the perspectives of team doctors regarding the communication process within the medical team and with other stakeholders in men's professional football. We conducted semistructured interviews with 10 team doctors from nine teams in six countries playing at the highest level of European professional football participating in the UEFA Elite Club Injury Study. Data were audio recorded, transcribed and analysed through reflexive thematic analysis. Three main themes described the communication process: (1) communication practices, (2) communication context and (3) communication foundation. The communication practices included involving specific stakeholders, using different communication channels and considering timing. The contextual factors in team structure, available resources and team standings require them to adapt their communication strategies. The foundation of effective communication relied on cultivating trust, acting respectfully, defining clear roles, following ethics and proactively developing relationships over time. In conclusion, the communication process is highly influenced by the context while team doctors constantly communicate with a diverse stakeholder group. This requires the team doctors to adapt to the different scenarios of professional football and dedicate time and effort to cultivating trustworthy relationships with stakeholders.

Tensiomyography, functional movement screen and counter movement jump for the assessment of injury risk in sport: a systematic review of original studies of diagnostic tests

Background

Scientific research should be carried out to prevent sports injuries. For this purpose, new assessment technologies must be used to analyze and identify the risk factors for injury. The main objective of this systematic review was to compile, synthesize and integrate international research published in different scientific databases on Countermovement Jump (CMJ), Functional Movement Screen (FMS) and Tensiomyography (TMG) tests and technologies for the assessment of injury risk in sport. This way, this review determines the current state of the knowledge about this topic and allows a better understanding of the existing problems, making easier the development of future lines of research.

Methodology

A structured search was carried out following the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines and the PICOS model until November 30, 2024, in the MEDLINE/PubMed, Web of Science (WOS), ScienceDirect, Cochrane Library, SciELO, EMBASE, SPORTDiscus and Scopus databases. The risk of bias was assessed and the PEDro scale was used to analyze methodological quality.

Results

A total of 510 articles were obtained in the initial search. After inclusion and exclusion criteria, the final sample was 40 articles. These studies maintained a high standard of quality. This revealed the effects of the CMJ, FMS and TMG methods for sports injury assessment, indicating the sample population, sport modality, assessment methods, type of research design, study variables, main findings and intervention effects.

Conclusions

The CMJ vertical jump allows us to evaluate the power capacity of the lower extremities, both unilaterally and bilaterally, detect neuromuscular asymmetries and evaluate fatigue. Likewise, FMS could be used to assess an athlete's basic movement patterns, mobility and postural stability. Finally, TMG is a non-invasive method to assess the contractile properties of superficial muscles, monitor the effects of training, detect muscle asymmetries, symmetries, provide information on muscle tone and evaluate fatigue. Therefore, they should be considered as assessment tests and technologies to individualize training programs and identify injury risk factors.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/view/CRD42024607563, PROSPERO (CRD42024607563).

Physical Performance Changes in Season are Associated with GPS Data in Soccer Players

This study investigated the associations between pre-season and in-season performance with external workload in professional soccer players. Twenty-one players completed hamstring strength, countermovement jump (CMJ), 20-m sprint, and Yo-Yo intermittent recovery tests before (pre-season) and after 8 weeks (in-season). External workload (total distance, high-intensity running distance, number of sprints, and power plays) was quantified during this period, and used to divide the average above and below subgroups outcome by outcome for further analyses. Significance was accepted when P≤0.05. Hamstring strength declined from pre- to in-season [- 6%; p=0.014; effect size (ES): - 0.41], while Yo-Yo performance improved (46%; p=0.001; ES: 1.31). When divided by high-intensity running distance, only the below-average subgroup improved CMJ performance (5%; p=0.030). For minutes played, the above-average subgroup improved Yo-Yo performance (41%; p<0.001), but not the below-average subgroup. Furthermore, playing time correlated with improved Yo-Yo performance (p=0.040; r=0.534). Improved 20-m sprint performance associated with more sprints performed (p=0.045; r=- 0.453). Physical capabilities changed over a competitive season and were related to, and differentiated by, external workload. Because hamstring strength decreased and CMJ only improved in players exposed to less high-intensity external load, practitioners should individualize approaches to counteract these conditions when high external workload is performed over the season.

The Single Leg Bridge Test Does Not Measure Isolated Hamstring Endurance in Healthy Men

Background

The Single Leg Bridge Test (SLBT) is commonly described as a measure of 'hamstring endurance'. Nevertheless, the relationship between the SLBT score and isolated hamstring endurance remains uncertain.

Purpose

This study aimed to investigate the correlation between SLBT scores and isolated hamstring endurance in healthy men. Additionally, the study aimed to assess the correlation between the limb symmetry index obtained from the SLBT and hamstring endurance test results.

Design

Cross-sectional study.

Methods

Forty healthy and physically active men were evaluated at the research laboratory on two separate occasions, with a minimum interval of 48 hours between visits. During each visit, participants performed either the single-leg balance test (SLBT) or the hamstring endurance test on an isokinetic dynamometer, which involved 30 concentric knee flexion repetitions performed at maximum intensity, with an angular velocity of 120°/s and a range of motion of 90°. Correlations were analyzed between SLBT scores and hamstring fatigue indexes provided by peak torque and work outcomes.

Results

The SLBT score (27±7 reps) demonstrated no significant correlation with isolated hamstring endurance, as measured by isokinetic peak torque (52±9%; p=0.737, r=-0.038) or work (57±9%; p=0.489, r=0.078). Likewise, the limb symmetry index obtained from the SLBT (99±12%) did not significantly correlate with index from the hamstring endurance test: peak torque (107±26%; p=0.540, r=-0.100) and work (102±18%; p=0.849, r=0.031).

Conclusion

The SLBT does not appear to be a suitable tool for measuring isolated hamstring endurance in healthy men.

Level of evidence

3.

The impact of a mid-season FIFA World Cup™ on injury occurrence and patterns in French professional soccer clubs

This study retrospectively compared the effect of holding the 2022 FIFA World Cup™ (WC) mid-season (season 2022/23) on injury rates and patterns in French Ligue 1 soccer clubs. Epidemiological data in 17 clubs were prospectively recorded by their physicians. Time-loss injuries (injuries leading to a player being unable to fully participate in play over the following 72-hour period) were compared with those reported during a regular season (2021-22). In the WC season, an increase of approximately 23% (training + match-play) was observed for both the total number of injuries and knee, ankle and muscle injuries combined. Incidences for match-play injury overall and for the knee, ankle and muscle regions combined and the hamstrings and calf regions specifically also rose significantly (range: p < 0.05-p < 0.01). These results suggest that injury occurrence and patterns in French L1 soccer clubs were substantially affected during the 2022/23 season when a mid-season WC was held.

The challenge of thigh tendon reinjuries: an expert opinion

This review critically examines the issue of thigh tendon reinjury in athletes, drawing on recent advancements and diverse perspectives in sports medicine. The findings underscore the paramount importance of an early and accurate diagnosis, which significantly influences treatment efficacy and rehabilitation outcomes. We explore the intricacies of tendon anatomy and the mechanisms underlying injuries, highlighting how these factors interplay with athlete-specific risk profiles to affect reinjury rates. A major finding from the review is the necessity for individualized rehabilitation approaches that integrate both traditional methods and emerging technologies. These technologies show promise in enhancing monitoring and facilitating precise adjustments to rehabilitation protocols, thus improving recovery trajectories. Additionally, the review identifies a common shortfall in current practices - premature to play (RTP) - which often results from inadequate adherence to tailored rehabilitation strategies or underestimation of the injury's severity. Such premature RTP significantly heightens the risk of further injury. Through this synthesis of contemporary research and expert opinion, the review advocates for a multidisciplinary approach in managing thigh tendon injuries, emphasizing the need for ongoing research to refine RTP criteria and optimize rehabilitation techniques. The ultimate goal is to support athletes in achieving safer and more effective recoveries, thereby reducing the likelihood of tendon reinjury.

Performing Lower-Limb Strength Exercises Before or After Training Does not Influence Fatigue Indices in Competitive Youth Soccer Players

ABSTRACT

Gantzer, C, Huff, D, Butterick, B, Chalmers, S, Marshall, P, Lovell, R, and Siegler, JC. Performing lower-limb strength exercises before or after training does not influence fatigue indices in competitive youth soccer players. J Strength Cond Res 38(10): 1760-1767, 2024-A multicenter approach was used to conduct a controlled, laboratory-based study ( Part A ) in conjunction with an ecologically focused, field-based study ( Part B ) of the influence of timing on hamstring fatigue induced by lower-limb strength exercises. Part A required players to perform the FIFA 11+ warm-up before a simulated soccer training session, whereas the other session involved removing the lower-limb strength exercises from the warm-up and delivering them after the simulated session. For Part B , players completed 2 live training sessions, where one session included the Nordic hamstring exercise (NHE) as part of a standardized warm-up before training and the other session incorporated the NHE at the end of training. Maximal hamstring force (MVC), rate of force development (RFD), countermovement jump (CMJ), and sprint speed (SS) were assessed before, during, and after the simulation and field training, respectively, to quantify fatigue across both study cohorts. There was no suggestion that timing of the intervention had an influence fatigue in either Part A or B , with no condition (MVC [ Part A & B ]: p > 0.43; RFD: p = 0.43; CMJ: p = 0.10; SS: p = 0.62), time (MVC: p > 0.30; RFD: p = 0.72; CMJ: p = 0.87; SS: p = 0.85), or interactions (MVC: p > 0.93; RFD: p = 0.78; CMJ: p = 0.99; SS: p = 0.94) evident. Our findings suggest youth soccer coaches should not be concerned with the timing of interventions, allowing them to focus instead on adherence and player buy-in.

Worst Case Scenarios in Soccer Training and Competition: Analysis of Playing Position, Congested Periods, and Substitutes

Aim: To understand mean (WCSmean) and peak (WCSpeak) worst case scenarios within training and game play in male professional soccer. Methods: Thirty-one (n = 31) first team players were monitored across 37 matches and 14 MD-3 sessions. Playing status was distinguished, football drills analyzed, and performance explored in long-period: >6 days, moderate-period: 5-6 days, and congested-period: ≤4 days. Relative total distance (TD), high-speed running distance (HSRD, >19.8 km·h-1), sprint distance (SD, >25.2 km·h-1), accelerations/decelerations (A+D, >3 m·s-2), accelerations (Acc, >3 m·s-2), and decelerations (Dec, >-3 m·s-2) were measured as well as Maximum acceleration (Max Acc; m·s-2) and deceleration (Max Dec; m·s-2). Results: Analysis of variance found differences between matches and training in WCSmean for TD, HSRD, SD, and Max Dec in all positions (p < .001; partial η2 > .275). Fullbacks displayed differences between match and training in Max Acc (moderate ESs; p < .001), while center backs and central midfielders in Max Dec (large ESs; p > .05). Main effects of playing status were discovered for all metrics except Max Dec (p < .001; partial η2 > .124). Analysis showed differences between long- and congested-period for A+D and Dec (large ESs; p ≤ .05). Conclusions: Findings provide more insights into short peak intensity demands of soccer showing that the maximum high velocity action of acceleration and deceleration is not being replicated in training. Nonstarters lack maximum intensity exposure in matches (WCSpeak) increasing the gap between training and competition even higher during congested fixture periods.

[Injury prevention in football : A challenge for team doctors and coaching team]

High injury rates and long injury-related downtimes demonstrate the need for effective and differentiated injury prevention strategies in football. Preventive measures should take place in various fields and should not be reduced to training programmes or medical approaches. The so-called "Big 6 of injury prevention" provide an overview of the key areas that should be addressed. In modern sports medicine, it should be a matter of course that the team doctor already participates in the primary prevention strategies and does not only get involved in the post-traumatic treatment. Similarly, a decision on a player's return to play after an injury should not be based solely on the medical assessment of the team doctor. Good communication and interdisciplinary cooperation, therefore, form the basis for successful prevention.

Longitudinal analysis of the incidence rate of injury in elite youth football: Trends over six years including the COVID-19 pandemic period

OBJECTIVES

We aimed to analyze injury trends and the possible effects of the coronavirus disease (COVID-19) pandemic on the incidence rates of injury in young elite football players.

DESIGN

A prospective cohort study design was adopted.

PARTICIPANTS

Our study included 832 male football players who suffered an injury during any of the six competitive seasons.

SETTING

An elite youth football academy.

MAIN OUTCOME MEASURE

Descriptive data and the incidence of injury were calculated. A generalized linear mixed model was used to assess differences in the occurrence of injury among the various age groups. Joinpoint regression was used to analyze injury trends.

RESULTS

Joinpoint regression models showed a statistically significant decrease in the incidence of injury in all age groups with an average annual percent change (AAPC) of 13.9 (95 %Confidence Interval [CI]:-23.2 - 3.4) and -13.5 (95 %CI:-24.5 to -0.9) for models with zero and one joinpoint, respectively. Football players in older age groups sustain a higher number of injuries, probably due to a higher number of matches and greater training intensity.

CONCLUSION

This study showed a downward trend in injuries in the participants prior to the pandemic, with an evident increase in the incidence rate of injury during the COVID-19 pandemic.

A musculoskeletal multifactorial individualised programme for hamstring muscle injury risk reduction in professional football: results of a prospective cohort study

Objective

To test whether a musculoskeletal multifactorial and individualised hamstring muscle injury (HMI) risk reduction programme could reduce HMI risk in professional football.

Methods

We conducted a prospective cohort study in Finnish premier football league teams, with the 2019 season used as a control and an intervention conducted in the 2021 season. Screening was conducted to provide individualised programmes and monitor progress. Cox regression with hazard ratio (HR) was used with HMI as outcome and season as explanatory variable, including all players for primary analysis and those who performed the two seasons for secondary analysis.

Results

90 players were included in the control and 87 in the intervention seasons; 31 players performed in the 2 seasons. Twenty HMIs were recorded during the control and 16 during the intervention seasons. Cox regression analyses revealed that HMI risk at any given time was not significantly different between control and intervention seasons (for all players: HR 0.77 (95% CI 0.39 to 1.51), p=0.444; for the 31 players: HR 0.32 (95% CI 0.01 to 1.29), p=0.110)). For the 31 players, the HMI burden was significantly reduced in the intervention compared with the control season (RR 0.67 (95% CI 0.53 to 0.85)). Higher compliance with knee strength training, maximal velocity exposure and lower performance reductions in maximal theoretical horizontal force and knee flexor force were associated with lower HMI incidence.

Conclusions

Although the primary analysis did not reveal any significant effect of the intervention to reduce HMI risk in professional football, the programme was feasible, and additional secondary analyses showed a significant association between the intervention and lower HMI burden, incidence and risk.

Building Bridges Instead of Putting Up Walls: Connecting the "Teams" to Improve Soccer Players' Support

The increase in the economic value of soccer occurred in parallel with an increase in competing demands. Therefore, clubs and federations evolved to greater specialization (e.g., state-of-the-art facilities and high-profile expertise staff) to support players' performance and health. Currently, player preparation is far from exclusively club or national team centered, and the lack of control in each player's environment can be more prevalent than expected. For example, an elite group of professional players faces disruptions in the season club-oriented planification due to involvement in national teams. Moreover, as elite players' financial resources grow, it is common for them to employ specialized personal staff (e.g., strength and conditioning, nutritionist, and sports psychologist) to assist in their preparation, resulting in complex three-fold relationships (i.e., club, player's staff, national team). Although efforts have been made to improve communication with and transition from the club to the national team supervision, this new reality (club-players' staff) may generate serious compound role-related problems and difficulties in monitoring load and training adaptation and having a unified message. Therefore, efforts must be implemented to ensure a more informed management of the players' performance environment, where the existence and impact of these various personal staff are considered to avoid a long-term non-zero sum for all intervening parties. If left unchecked, current professional thinking may collide or overlap, potentially triggering conflict escalation and impairing athletic performance or health, especially if effective communication routes are not adequately established. Moreover, diluted personal responsibility regarding performance may ensue, resulting in decreased productivity from all involved, which may cause more harm than benefits for the player's overall health and performance. This emerging reality calls for developing a joint working framework (i.e., between the player's personalized support team and the clubs' team) and better managing of a player-centered process.

Changes in head staff members in male elite-level football teams are associated with increased hamstring injury burden for that season: the UEFA Elite Club Injury Study

Objective

To evaluate whether a change of head coach or other head staff before or during a season is correlated to hamstring injury (HI) burden in male elite-level football (soccer) in Europe.

Methods

The survey was conducted using a questionnaire reporting any staff change within the team. Data about the head staff changes and hamstring injury burdens were collected from 14 teams participating in the Elite Club Injury Study (ECIS) during the 2019/2020, 2020/2021 and 2021/2022 seasons.

Results

On average, replacing the head coach before or during a season happens in every second season. All changes, except for the change of the head coach during a season, indicate an association with an increase in HI burden (ranging from 10% to 81%). However, only changes in the fitness coach and team doctor roles reached statistical significance. The HI burden seems to be influenced by adding new staff members, such as the head of fitness/performance coach in 36% of the teams and the team doctor in 17%. New head coaches starting the season with their own, for the team new, fitness/performance coach was highly associated with increased HI burden (p<0.001).

Conclusions

Bringing their own fitness/performance coaches is common for managers entering a new elite male football club. However, this paper has highlighted that this trend seems to lead to a three times increase in HI burden. Similarly, replacing the team doctor was also associated with increased HI burden. Instability among head staff members in male elite-level football teams seems associated with increased HI burden during the season.

Effects of muscle fatigue on exercise-induced hamstring muscle damage: a three-armed randomized controlled trial

PURPOSE

Hamstring injuries in soccer reportedly increase towards the end of the matches' halves as well as with increased match frequency in combination with short rest periods, possibly due to acute or residual fatigue. Therefore, this study aimed to investigate the effects of acute and residual muscle fatigue on exercise-induced hamstring muscle damage.

METHODS

A three-armed randomized-controlled trial, including 24 resistance-trained males, was performed allocating subjects to either a training group with acute muscle fatigue + eccentric exercise (AF/ECC); residual muscle fatigue + eccentric exercise (RF/ECC) or a control group with only eccentric exercise (ECC). Muscle stiffness, thickness, contractility, peak torque, range of motion, pain perception, and creatine kinase were assessed as muscle damage markers pre, post, 1 h post, and on the consecutive three days.

RESULTS

Significant group × time interactions were revealed for muscle thickness (p = 0.02) and muscle contractility parameters radial displacement (Dm) and contraction velocity (Vc) (both p = 0.01), with larger changes in the ECC group (partial η2 = 0.4). Peak torque dropped by an average of 22% in all groups; stiffness only changed in the RF/ECC group (p = 0.04). Muscle work during the damage protocol was lower for AF/ECC than for ECC and RF/ECC (p = 0.005).

CONCLUSION

Hamstring muscle damage was comparable between the three groups. However, the AF/ECC group resulted in the same amount of muscle damage while accumulating significantly less muscle work during the protocol of the damage exercise.

TRIAL REGISTRATION

This study was preregistered in the international trial registration platform (WHO; registration number: DRKS00025243).

What Factors Do Clinicians, Coaches, and Athletes Perceive Are Associated With Recovery From Low Back Pain in Elite Athletes? A Concept Mapping Study

OBJECTIVE: Identify factors that elite sport clinicians, coaches, and athletes perceive are associated with low back pain (LBP) recovery. DESIGN: Concept mapping methodology. METHOD: Participants brainstormed, sorted (thematically), and rated (5-point Likert scales: importance and feasibility) statements in response to the prompt, "What factors are associated with the recovery of an elite athlete from low back pain?" Data cleaning, analysis (multidimensional scaling, hierarchical cluster analysis, and descriptive statistics), and visual representation (cluster map and Go-Zone graph) were conducted following concept mapping guidelines. RESULTS: Participants (brainstorming, n = 56; sorting, n = 34; and rating, n = 33) comprised 75% clinicians, 15% coaches, and 10% athletes and represented 13 countries and 17 sports. Eighty-two unique and relevant statements were brainstormed. Sorting resulted in 6 LBP recovery-related themes: (1) coach and clinician relationships, (2) inter-disciplinary team factors, (3) athlete psychological factors, (4) athlete rehabilitation journey, (5) athlete non-modifiable risk factors, and (6) athlete physical factors. Participants rated important recovery factors as follows: athlete empowerment and psychology, coach-athlete and athlete-clinician relationships, care team communication, return-to-sport planning, and identifying red flags. CONCLUSION: Factors perceived as important to LBP recovery in elite athletes align with the biopsychosocial model of community LBP management. Clinicians should consider that an athlete's psychology, relationships, care team communication, and rehabilitation plan may be as important to their LBP recovery as the formulation of a diagnosis or the medications or exercises prescribed. J Orthop Sports Phys Ther 2023;53(10):1-16. Epub 10 August 2023. doi:10.2519/jospt.2023.11982.

Epidemiology of Injuries in Professional and Amateur Football Men (Part II)

Background (1): Men's football is a physically demanding contact sport that involves intermittent bouts of sprinting, jogging, walking, jumping and changes of direction. The physical demands of the game vary by level of play (amateur club, sub-elite and open club or international), but injury rates at all levels of the men's football game remain the highest of all sports. Objective: The aim of this study is to conduct a systematic review of data from the epidemiological literature regarding the profile, severity and mechanisms of injuries and the frequency of recurrent injuries in professional and amateur football players. Methods (2): A systematic review, according to PRISMA guidelines, was performed up to June 2023 in the databases of PubMed, Web of Science, Google academic, Google scholar and the Diva portal. Twenty-seven studies that reported data on the type, severity, recurrence and mechanisms of injury in professional and amateur men's football were selected and analyzed. Two reviewers independently audited data and assessed the study quality using the additional and adapted version of the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement and the Newcastle Ottawa Scale (NOS) to assess risk of bias for the quality of external validity. Results (3): In professional male football players, the mean prevalence of muscle/tendon injuries was 39.78%, followed by joint and ligament injuries-21.13%, contusions-17.86%, and fractures-3.27%, and for amateur football players, the prevalence's were 44.56% (muscle/tendon injuries), 27.62% (joint and ligament injuries), 15.0% (contusions) and 3.05% (fracture), respectively. The frequency of traumatic injuries was higher in amateur football players (76.88%) compared to professional football players (64.16%), the situation being reversed in the case of overuse injuries: 27.62% in professional football players and 21.13% in amateur football players. Most contact injuries were found in professional footballers (50.70%), with non-contact injuries predominating in amateur footballers (54.04%). The analysis of the severity of injuries showed that moderate injuries dominated in the two categories of footballers; the severe injuries in amateur footballers exceeded the severe injuries recorded in professional footballers by 9.60%. Recurrence proportions showed an inverse relationship with the level of play, being higher in amateur footballers (16.66%) compared to professional footballers (15.25%). Conclusions (4): Football-related injuries have a significant impact on professional and amateur football players and their short- and long-term health status. Knowing the frequency of severe diagnoses, such as strains, tears and cramps of the thigh muscles, ankle ligament sprains and hip/groin muscle strain requires the establishment of adequate programs to prevent them, especially in amateur football players, who are more prone to serious injuries.

Most modifiable risk factors for hamstring muscle injury in women's elite football are extrinsic and associated with the club, the team, and the coaching staff and not the players themselves: the UEFA Women's Elite Club Injury Study

PURPOSE

To describe the perceived importance of suggested hamstring injury risk factors according to chief medical officers (CMOs) of European women's professional football clubs. A secondary objective was to compare if these perceptions differed between teams with a lower-than-average and higher-than-average hamstring injury burden.

METHODS

The CMOs of eleven European professional women's football clubs were initially asked to suggest modifiable risk factors for hamstring injury. These risk factors were rated in according with their perceived importance on a 5-graded Likert scale. Participating teams were divided in two groups depending on their hamstring injury burden during the 2020/21 season. The LOW group consisted of six teams that had a lower-than-average hamstring injury burden. The HIGH group consisted of five teams that had a higher-than-average hamstring injury burden.

RESULTS

Twenty-one risk factors were suggested, most of which were extrinsic in nature, hence associated with the coaching staff, the team or the club organization rather than with the players themselves. The risk factors with the highest average importance were: "lack of communication between medical staff and coaching staff" and "load on players" (each with a weighted average of 3.9), followed by "lack of regular exposure to high-speed football actions during training" and "playing matches 2-3 times a week" (weighted average of 3.8 and 3.7). Differently from the LOW group, the HIGH group perceived the coaching factors (style of coach leadership, training/exercise surveillance by coaching staff) as more important.

CONCLUSION

In accordance to the eleven CMOs recruited in this study, most risk factors for hamstring injuries are extrinsic in nature and associated with the club, the team, and the coaching staff, and not the players themselves.

LEVEL OF EVIDENCE

Level III.