Time-loss injuries and illnesses at the FIFA world cup Qatar 2022.

The study aimed to analyse incidence and characteristics of time-loss injuries and illnesses during the FIFA World Cup Qatar 2022. Of 838 male football players, 705 consented to participate. Team medical staff reported 82 time-loss injuries, corresponding to an injury event incidence of 5.6 injuries/1000 h of total exposure (95%CI 4.5 to 7.0 injuries/1000 h), with a median of 2 time-loss injury events per team (IQR, 1 to 4.5, range 0-7). The total injury burden was 103 (95% CI 61 to 152) days per 1000 h. Muscle/tendon injuries had the highest incidence of tissue types (48 cases, 3.3/1000 h (95% CI 2.5 to 4.4), and hamstring muscle injuries were the most frequent diagnosis (16 cases, incidence 1.1/1000 h, 95% CI 0.6 to 1.8). Match injury event incidence was 20.6/1000 h (15.0 to 27.7) and training injury event incidence was 2.1/1000 h (1.4 to 3.1). The majority (52%) of sudden-onset injuries were non-contact injuries, 40% direct contact and 8% indirect contact. We recorded 15 time-loss illnesses, corresponding to an illness event incidence of 1.1 per 1000 competition days, (95% CI: 0.6 to 1.8), and illness burden of 2.1 (1.0 to 3.4) days lost per 1000 competition days. The most common illness was respiratory infection (12 cases, 80%). Match injury event incidence was the lowest in any FIFA World Cup since injuries have been monitored.

Comprehensive periodic health evaluations of 454 Norwegian Paralympic and Olympic athletes over 8 years: what did we learn?

OBJECTIVE: A periodic health evaluation (PHE) is a comprehensive and multidisciplinary investigation of athlete health widely used in elite sport, but its contents and benefits can be questioned. This study aimed to determine the prevalence of conditions identified by a PHE among Paralympic and Olympic athletes over four consecutive Games cycles from Rio de Janeiro 2016 to Beijing 2022 and to assess the benefits and potential pitfalls of a comprehensive PHE programme in detecting existing injuries, illnesses and other health issues. METHODS: We collected extensive health history and clinical examination data on elite athletes: medical history, ECG, blood pressure, blood samples, spirometry, musculoskeletal health, cognitive function, mental health and compliance with public health programmes. RESULTS: The final cohort included 87 Paralympic and 367 Olympic athletes, representing 565 PHE cycles. Musculoskeletal problems and unspecified pain, infections and allergies were the most frequent health issues. High blood pressure was the most prevalent cardiovascular finding, and vitamin D deficiency the most common laboratory abnormality. Most athletes complied with the public childhood vaccination programmes, but fewer with recommended cancer screening. Follow-up of health issues was variable. CONCLUSION: Our PHE programme identified musculoskeletal problems, infections, allergies, elevated blood pressure and vitamin D deficiency as common health conditions. Longitudinal follow-up of health conditions identified during screening and improved compliance with public health and cancer screening programmes is needed to determine the true benefits of athlete care prompted by the PHE.

Causal inference did not detect any effect of jump load on knee complaints in elite men's volleyball.

The aim was to determine how jump load affects knee complaints in elite men's volleyball. We collected data from four men's premier league volleyball teams through three seasons in a prospective cohort study (65 players, 102 player-seasons). Vert inertial measurement devices captured the jump load (jump frequency and jump height) from 21 088 daily player sessions, and knee complaints were reported in 3568 weekly OSTRC-O questionnaires. Mixed complementary log-log regression models described the probability of (i) experiencing symptoms if players were currently asymptomatic, (ii) worsening symptoms if players had symptoms, and (iii) recovery from knee complaints. Based on our causal assumptions, weekly jump load was modeled as the independent variable, adjusted for age (years), weight (kg), position on volleyball team, and past jump load. No certain evidence of an association was found between weekly jump load and probability of (i) knee complaints (p from 0.10 to 0.32 for three restricted cubic splines of load), (ii) worsening symptoms if the player already had symptoms (p from 0.11 to 0.97), (iii) recovery (p from 0.36 to 0.63). The probability of knee complaints was highest for above-average weekly jump load (~1.2% for an outside hitter with mean age and height) compared with low loads (~1%) and very high loads (→ ~ 0%). The association between jump load and knee complaints risk remains unclear. Small differences in risk across observed jump load levels were observed. It would likely require substantially increased sample sizes to detect this association with certainty.

Groin injuries in women's premier league football in Norway: A two-season prospective cohort study describing clinical and imaging characteristics.

OBJECTIVE: To describe the prevalence, incidence, and burden of groin injuries in the Norwegian women's premier football league and to describe their clinical and imaging characteristics. METHODS: During the 2020 and 2021 seasons, players in the Norwegian women's premier league reported groin injuries weekly, using the Oslo Sports Trauma Research Centre Questionnaire on Health Problems (OSTRC-H2). We calculated weekly prevalence, incidence, and burden of groin injuries. The team physical therapists classified the player-reported injuries based on the Doha classification system. Injuries with more than 3 days' time loss or reported in 2 consecutive weeks were eligible for magnetic resonance imaging (MRI). RESULTS: On average, 3.9% (95% CI: 3.4-4.4) of players reported a groin injury at any time; of which 78% caused time loss. The incidence rate was 1.6 injuries/1000 h (95% CI: 1.3-2.0) and their burden was 11 days lost/1000 h. The physical therapists examined 67 of 124 player-reported groin injuries (53%). Adductor-related injury was most common (55%) followed by iliopsoas (15%) and rectus femoris-related (12%). Pubic-related injuries caused most time loss (median: 24 days, IQR: 5-133). In this study, 42 injuries were investigated with MRI; 8 (19%) showed no changes, 6 (14%) an acute musculotendinous lesion, and 32 (76%) a nonacute finding (e.g., central symphyseal disc protrusion, tendinopathies). CONCLUSION: The incidence rate and burden of groin injuries were high. Adductor-related injuries were most common, but pubic-related injuries caused most time loss. Most MRI examinations demonstrated nonacute findings.

Exploring Growth, Maturity, and Age as Injury Risk Factors in High-Level Youth Football.

Rapid somatic growth and biological maturity status may affect injury patterns in youth football, yet firm conclusions cannot be drawn from the existing research. We aimed to explore growth velocity, maturity, and age as injury risk factors in 95 academy players (11.9-15.0 years), using anthropometric (height and body mass), maturity (skeletal age), injury, and football exposure data collected prospectively over three seasons (2016/17-2018/19). We compared the relative quality of mixed-effects logistic regression models with growth velocity for 223 growth intervals (average 113 days) included as fixed effects and adjusted for age (chronological or skeletal) plus load (hours/week). Associations were considered practically relevant based on the confidence interval for odds ratios, using thresholds of 0.90 and 1.11 to define small beneficial and harmful effects, respectively. We observed harmful effects of older age on overall (OR: 2.61, 95% CI: 1.15-5.91) and sudden onset (1.98, 1.17-3.37) injury risk. Significant associations (p<0.05) were observed for higher body mass change and greater maturity on sudden onset injuries, and for higher hours/week on gradual onset, bone tissue, and physis injuries. Future studies should include larger samples, monitoring athletes from pre-adolescence through maturation, to enable within-subject analyses and better understand the relationship between growth, maturation, and injuries.

Knee, Low Back, and Shoulder Problems Among University and Professional Volleyball Players: Playing With Pain.

CONTEXT: The knee, low back, and shoulder account for most overuse injuries in volleyball. Previous researchers have used methodology that did not examine the extent of injury burden and effect on performance. OBJECTIVE: To develop a more accurate and complete understanding regarding the weekly prevalence and burden of knee, low back, and shoulder problems within the highest levels of men's volleyball, including the role that preseason complaints, match participation, player position, team, and age have on complaints. DESIGN: Descriptive epidemiology study. SETTING: Professional volleyball clubs and the National Collegiate Athletic Association Division I program. PATIENTS OR OTHER PARTICIPANTS: A total of 75 male volleyball players, representing 4 teams playing in their country's respective premier league (Japan, Qatar, Turkey, and the United States), participated over a 3-season period. MAIN OUTCOME MEASURE(S): Players completed a weekly questionnaire (Oslo Sports Trauma Research Centre Overuse Injury Questionnaire) reporting pain related to their sport and the extent to which knee, low back, and shoulder problems affected participation, training volume, and performance. Problems leading to moderate or severe reductions in training volume or performance or the inability to participate were considered substantial problems. RESULTS: The mean weekly prevalence of knee, low back, and shoulder problems based on 102 player-seasons was 31% (95% CI = 28%, 34%), 21% (95% CI = 18%, 23%), and 19% (95% CI = 18%, 21%), respectively. Most players (93%, 95/102 player-seasons) reported some level of knee (79%, n = 81/102 player-seasons), low back (71%, n = 72/102 player-seasons), or shoulder (67%, n = 68/102 player-seasons) complaints during the season. Most players (58%, n = 59/102 player-seasons) experienced at least 1 episode of substantial problems affecting the knee (33%, n = 34/102 player-seasons), low back (27%, n = 28/102 player-seasons), or shoulder (27%, n = 28/102 player-seasons). Players with preseason complaints had more in-season complaints than teammates without preseason problems (mean weekly prevalence: knee, 42% versus 8%, t49 = -18.726, P < .001; low back, 34% versus 6%, t32 = -12.025, P < .001; shoulder, 38% versus 8%, t30 = -10.650, P < .001). CONCLUSION: Nearly all included elite male volleyball players experienced knee, low back, or shoulder problems, and most had at least 1 bout that substantially reduced training participation or sport performance. These findings suggest that knee, low back, and shoulder problems result in greater injury burden than previously reported.

Injury and illness among Norwegian Olympic athletes during preparation for five consecutive Summer and Winter Games.

OBJECTIVE: To describe the patterns of health problems among Norwegian Olympic candidates during their preparations for five consecutive Olympic Games (London 2012, Sochi 2014, Rio de Janeiro 2016, PyeongChang 2018 and Tokyo 2020). METHODS: This was a descriptive epidemiological study using the Oslo Sports Trauma Research Center Questionnaire on Health Problems to collect data on all self-reported health problems from Norwegian Olympic candidate athletes for 12-18 months prior to each Olympic Games. Team physicians and physiotherapists followed up the athlete reports, providing clinical care and classifying reported problems according to the International Olympic Committee 2020 consensus statement on methods for recording and reporting of epidemiological data on injury and illness in sport. RESULTS: Between 2011 and 2020, 533 athletes were included in the Norwegian Olympic team monitoring programme, with a 78% response to the weekly questionnaire. During this time, athletes reported 2922 health problems, including 1409 illnesses (48%), 886 overuse injuries (repetitive mechanism, 30%) and 627 acute injuries (traumatic mechanism, 21%). Diagnostic codes were recorded for 2829 (97%) of health problems. Athletes reported, on average, 5.9 new health problems per year (95% CI: 5.6 to 6.1), including 1.3 acute injuries (CI: 1.2 to 1.4), 1.7 overuse injuries (CI: 1.6 to 1.9) and 2.9 illnesses (CI: 2.7 to 3.0). Each year, female and male athletes lost an average of 40 and 26 days of training and competition due to health problems, respectively. The diagnoses with the highest health burden were anterior cruciate ligament rupture, respiratory infection, lumbar pain and patellar tendinopathy. CONCLUSION: The injury burden was particularly high among female athletes and in team sports, whereas endurance sports had the greatest burden of illness. Our data provide a compelling argument for prioritising medical care and investing in prevention programmes not just during the Olympic Games, but also the preparation period.

#ReadyToPlay: health problems in women's football-a two-season prospective cohort study in the Norwegian premier league.

OBJECTIVES: To describe the prevalence, incidence and burden of all health problems in the Norwegian women's premier league. METHODS: During the 2020 and 2021 seasons, players in the Norwegian women's premier league reported all health problems (sudden-onset injuries, gradual-onset injuries and illnesses) weekly, using the Oslo Sports Trauma Research Centre Questionnaire on Health Problems. Team medical staff diagnosed reported problems using the Sport Medicine Diagnostic Coding System. We calculated average weekly prevalence, incidence and burden of all health problems reported. RESULTS: We included 294 players (age: 22±4 years) from 11 teams. Response rate to the weekly questionnaire was 79%. On average, 32% (95% CI: 31% to 33%) of the players reported at least one health problem at any time and 22% (95% CI: 21% to 23%) reported a substantial health problem negatively affecting their training volume or performance. The overall incidence was 10.7 health problems per 1000 hours of football exposure. Sudden-onset injuries were most severe (68% of the total time loss), followed by gradual-onset injuries (25%) and illnesses (8%). Thigh was the most common injury location (26%), while knee injuries were most severe, causing 42% of the total injury time loss. Anterior cruciate ligament (ACL) injuries alone caused 30% of the total injury time loss. CONCLUSION: One in five players had a health problem negatively affecting their training volume or performance at any time. Sudden-onset injuries represented the most burdensome health problem. Thigh injuries were most frequent, while knee injuries, ACL injuries especially, were most severe.

Performing Nordic hamstring strength testing with additional weight affects the maximal eccentric force measured: do not compare apples to oranges.

Background: Nordic hamstring test devices are commonly used to measure maximal eccentric hamstring force. The ability to control the final phase of the exercise has been adopted as a criterion to add weight when testing, without substantial evidence. We investigated if adding weight affected the maximal force measured, and if there were differences between players who could and could not control the final phase. Methods: Female (n=84) and male (n=56) football players performed a Nordic hamstring strength test with 0, 5 and 10 kg. We used visual inspection to assess the ability to control the final phase (approximately last 20°), as per previously published studies. Results: Maximal force was higher when tested with 5 kg (females: +8 N (2%), p<0.001; males: +18 N (4%), p<0.001) and 10 kg (females: +17 N (5%), p<0.001; males: +27 N (6%), p<0.001) compared with 0 kg. This was the case for both groups, those who could control the final phase (5 kg: +16 N (4%), p<0.001; 10 kg: +28 N (7%), p<0.001) and those who could not (5 kg: +9 N (3%), p<0.001; 10 kg: +15 N (4%), p<0.001). Conclusion: Both players who could and could not control the final phase of the Nordic hamstring test demonstrated higher maximal force when adding weight to testing. Therefore, this should not be used to decide if players should perform testing with or without weight. Either all participants or none should be tested with weight, and the same approach should be used both for pre-testing and post-testing.

Fractures in professional footballers: 7-years data from 106 team seasons in the Middle East.

Epidemiological studies on fractures in European professional football (soccer) are in abundance. However, such data are lacking in Middle Eastern professional footballers and information on fracture treatment is scarce. The aim of this study is to describe the epidemiology of fractures across seven seasons in Qatar Stars League (QSL) footballers. A prospective study of fractures in professional male footballers over 7 consecutive seasons (2013 to 2020), involving 3255 players and 106 team' seasons. Time loss and injuries and illnesses were recorded using standardised digital tools in accordance with international consensus procedures. Fractures were recorded according to onset mechanism, location, diagnoses, treatment and return to play. A total of 108 players sustained fractures during 638,247 hours of player exposure (88.9% training and 11.1% matches), representing 2.7% of all time-loss injuries. The incidence was 0.17 fractures per 1000 h of exposure (match and training incidence of 0.9 and 0.07 fractures / 1000 h, respectively), equivalent to an average of one fracture per team per season. Fractures mostly occurred in the feet (28.2%), hands (21.1%), shoulders (11.3%) and head (i.e., face) (9.9%). Mean (median) absence was 71 (47 days), with 4.6% refractures. Only 34.3% of the fractures required surgery and nearly all players (98.1%) returned to play at the professional level. Almost all professional football players with fractures return to play at the same competitive level after an average of 10 weeks of absence (mean absence was 71 ± 81 (median: 47, Inter Quartile Range [14-93]) days). One in ten continue to play with symptoms and one in twenty may refracture. Long-term effects of fractures are still unknown.

Impact of COVID-19 lockdown on injury risk in Qatar's professional football.

OBJECTIVES: To compare injury incidence, burden and characteristics between the pre- and post-COVID-19 lockdown periods in Qatari professional football. DESIGN: Prospective cohort study. METHODS: Injury and exposure data for two post-COVID-19 lockdown periods [early post-lockdown period: short-term ~2 months (54 matches) and late post-lockdown period: long-term 8-months (183 matches)] were compared to the benchmark of the same periods from the three previous seasons (2017/18-2019/20). RESULTS: We observed no difference in overall, training or match incidence between early post-lockdown period and the benchmark reference. However, this short-term period resulted in lower burden for overall- (RR 0.80, P < 0.0001), training- (RR 0.73, P < 0.0001) and match-injuries (RR 0.40, P < 0.0001) compared to the benchmark. During late post-lockdown period match injury incidence (RR 0.72, P = 0.0010) and match injury burden (RR 0.69, P < 0.001) were lower than the benchmark. In contrast, both overall- (RR 1.30, P < 0.001) and training-injury burden (RR 1.65, P < 0.001) were higher. A significant increase in adductor strains in both post-lockdown periods was observed. CONCLUSIONS: Immediately after the COVID-19 lockdown (short-term effect), there was no difference in injury incidence but a lower injury burden compared to benchmark. Moreover, the rapid return to competition for the successive season (long-term effect) was associated with a higher overall- and training-injury burden, but a lower match-injury burden compared to the benchmark.

Unsupervised field-based exercise challenge tests to support the detection of exercise-induced lower airway dysfunction in athletes.

Background: Athletes are at risk for developing exercise-induced lower airway narrowing. The diagnostic assessment of such lower airway dysfunction (LAD) requires an objective bronchial provocation test (BPT). Objectives: Our primary aim was to assess if unsupervised field-based exercise challenge tests (ECTs) could confirm LAD by using app-based spirometry. We also aimed to evaluate the diagnostic test performance of field-based and sport-specific ECTs, compared with established eucapnic voluntary hyperpnoea (EVH) and methacholine BPT. Methods: In athletes with LAD symptoms, sensitivity and specificity analyses were performed to compare outcomes of (1) standardised field-based 8 min ECT at 85% maximal heart rate with forced expiratory volume in 1 s (FEV1) measured prechallenge and 1 min, 3 min, 5 min, 10 min, 15 min and 30 min postchallenge, (2) unstandardised field-based sport-specific ECT with FEV1 measured prechallenge and within 10 min postchallenge, (3) EVH and (4) methacholine BPT. Results: Of 60 athletes (median age 17.5; range 16-28 years.; 40% females), 67% performed winter-sports, 43% reported asthma diagnosis. At least one positive BPT was observed in 68% (n=41/60), with rates of 51% (n=21/41) for standardised ECT, 49% (n=20/41) for unstandardised ECT, 32% (n=13/41) for EVH and methacholine BPT, while both standardised and unstandardised ECTs were simultaneously positive in only 20% (n=7/35). Standardised and unstandardised ECTs confirmed LAD with 54% sensitivity and 70% specificity, and 46% sensitivity and 68% specificity, respectively, using EVH as a reference, while EVH and methacholine BPT were both 33% sensitive and 85% specific, using standardised ECTs as reference. Conclusion: App-based spirometry for unsupervised field-based ECTs may support the diagnostic process in athletes with LAD symptoms. Trial registration number: NCT04275648.

Performance and symmetry measures during vertical jump testing at return to sport after ACL reconstruction.

OBJECTIVE: Vertical jump tests are more sensitive in revealing asymmetries in performance metrics at the time of return to sport after anterior cruciate ligament (ACL) reconstruction (ACLR) than horizontal hop tests. However, it remains unclear which vertical tests (bilateral or unilateral) and which metrics (kinetics or performance) are most effective in informing the rehabilitation status and readiness for return to sport. We aimed to investigate the status of athletes during vertical jump testing at return to sport after ACLR. METHODS: A dual force platform system was used to evaluate jumping performance of 126 recreational and professional athletes at the time of return to sport after ACLR, as well as 532 healthy control participants. Performance and kinetic metrics were collected during four jump tests: double-leg countermovement jump, single-leg countermovement jump, double-leg 30 cm drop jump and single-leg 15 cm drop jump. Between-limb and between-group differences were explored using mixed models analyses. RESULTS: At the time of return to sport after ACLR, athletes still presented significant differences favouring the uninvolved side, particularly in the symmetry of the concentric impulse (p<0.001) in all jumps compared with the control group. Peak landing force asymmetry was greater in the ACLR group than the controls during the countermovement (p<0.001, MD=-11.6; 95% CI -15.4 to -7.9) and the double-leg drop jump (p=0.023, MD=-8.9; 95% CI -14.9 to -2.8). The eccentric impulse asymmetry was significantly greater (p=0.018, MD=-3.8; 95% CI -5.8 to -1.7) in the ACLR group during the single-leg drop jump only. Jump height was significantly lower (p<0001) in the ACLR group compared with controls in all tests except the double-leg drop jump. CONCLUSION: At the time of return to sport after ACLR, despite passing the traditional discharge criteria, athletes remained asymmetrical during all vertical jump tests, in the concentric (push-off) phase, during landing from bilateral jumps and for most performance metrics. Clinicians should aim to restore not only symmetry in ground reaction forces but also absolute performance metrics such as jump height, reactive strength index and contact times, to potentially reduce injury risk and improve overall athletic performance.

A 3-year population-based study of exercise-related sudden cardiac arrest among 12- to 50-year-old Norwegians.

INTRODUCTION: Regular exercise is associated with reduced risk of cardiovascular disease. Paradoxically, an increased risk of sudden cardiac arrest (SCA) is documented during or immediately after exercise and in athletes compared to the nonathletic population. Our objective was to identify, through multiple sources, the total number of exercise-related versus non-exercise-related SCA in the young population in Norway. METHODS: We collected primary data from the prospective Norwegian Cardiac Arrest Registry (NorCAR) for all patients aged 12-50 suffering SCA of presumed cardiac cause from 2015 to 2017. We collected secondary data about prior physical activity and the SCA, through questionnaires. We searched media reports for SCA incidents in sports. Exercise-related SCA is defined as SCA during or <1 h after exercise. RESULTS: Overall, 624 patients, median age 43 years, were included from NorCAR. Two thirds (393) replied to the study invitation, of whom 236 answered the questionnaires: 95 survivors and 141 next of kin. The media search resulted in 18 relevant hits. With a multiple source approach, we identified 63 cases of exercise-related SCA, equivalent to an incidence of 0.8/100 000 person-years, versus 7.8/100 000 person-years of non-exercise-related SCA. Among those who answered (n = 236), almost two thirds (59%) exercised regularly, most commonly (45%) 1-4 h/week. Endurance exercise (38%) was the most prevalent type of regular exercise and the most common activity during exercise-related SCA (53%). CONCLUSION: The burden of exercise-related SCA was low (0.8 per 100 000 person-years) and ten times lower than non-exercise-related SCA in the young population in Norway.

Mechanisms of ACL injuries in men's football: A systematic video analysis over six seasons in the Qatari professional league.

To assess the mechanisms of ACL injury in male professional football players in Qatar across multiple seasons using systematic video analysis. 15 ACL injuries occurred in competition among the professional football teams that participated in an injury Surveillance Programme during 6 seasons (2013/2014 to 2018/2019). High-definition broadcast videos of these injuries were analyzed (49 views; 34 slow motion) by five analysts who independently described the injury mechanisms (situation, behavior, biomechanical characteristics) using validated observational tools. A knee valgus mechanism was observed in two-thirds of the cases (1 with direct contact to the knee, 3 with indirect contact (other body parts) and 6 with no contact). No visible valgus was reported in 2 of the direct knee contact injuries, while 3 cases of non-contact and indirect contact injuries were unclear. We observed 4 main categories of injury situation among those (n = 12) classified as non-contact/ indirect contact (multiple combinations were possible): pressing (n = 6), tackling or being tackled (n = 4), blocking (n = 3) and screening (n = 2). Direct contact injuries (n = 3) were suffered by 2 players during tackling and 1 whilst being tackled. Contact injuries represented only 20% of ACL injuries occurring during competition in Qatari professional soccer players. Independent of the playing situation, knee valgus was frequently observed (10/15 cases). Pressing was the most common situation (6/15 cases) leading to injury. Landing after heading was not reported in any of these ACL injuries.

Associations between health problems and athlete burnout: a cohort study in 210 adolescent elite athletes.

Objectives: We studied associations between the burden of health problems and athlete burnout in a population of athletes from Norwegian Sport Academy High Schools. Methods: This is a mixed prospective/retrospective cohort study. We included 210 athletes, 135 boys and 75 girls, from endurance, technical and team sports. We used the Oslo Sports Trauma Centres Questionnaire for Health Problems to collect 124 weeks of health data. During the first 26 weeks, athletes reported the health data prospectively using a smartphone app. For the following 98 weeks, we collected health data by interviewing athletes at the end of their third year in Sport Academy High School. At the time of the interview, the athletes also completed a web-based questionnaire, including the Athlete Burnout Questionnaire and covering social relations in sports and school, coach relations and living conditions. Results: A greater burden of health problems was associated with a higher score for athlete burnout (B: 0.16, 95% CI 0.09 to 0.22, p<0.001). In a multivariable model, this was true for both illnesses (B: 0.21, 95% CI 0.10 to 0.32, p<0.001), acute injuries (B: 0.16, 95% CI 0.04 to 0.27, p=0.007) and overuse injuries (B: 0.10, 95% CI 0.002 to 0.18, p=0.011). This was also true in gender and sports category subgroups. The coach having a high influence on training week was associated with a lower score for athlete burnout. Conclusion: A greater burden of health problems was associated with greater symptoms of athlete burnout in athletes attending Sport Academy High Schools.

Obstacles and opportunities for injury prevention in professional football in Qatar: exploring the implementation reality.

Background: Research focusing on reducing the risk of injuries has increased over the last two decades showing that prevention implementation in real life is challenging. Objective: To explore the experience and opinions of professional football stakeholders regarding injuries, their prevention and the implementation of preventive measures. Design: Qualitative study. Setting: Technical and medical staff from Qatar's premier football league. Participants: 22 professionals from 6 teams. Main outcome: Semistructured interviews were transcribed verbatim and analysed using the thematic analysis method. Results: All the participants acknowledged the importance of injury prevention. They mentioned teamwork, trust and communication as critical factors for a successful injury prevention implementation. Teams' doctors see themselves mainly involved in the treatment and recovery process, and to a lesser degree, in the prevention process. Physiotherapists defined their primary responsibilities as screening for injury risk and providing individual exercises to players. The participants declared that the fitness coach is responsible for injury prevention implementation. All stakeholders reported that the fitness coach plays a vital role in communication by bridging the head coach and the medical staff. Stakeholders reported that the Qatari football league has a very particular context around the player, such as socioecological factors influencing injury prevention implementation. Conclusions: The fitness coach plays a vital role in the injury prevention implementation system, as one of the key actors for the process, as well as the bridge between the medical team and the head coach, resulting from their better communication with the head coaches. The findings support considering and understanding the contextual factors during the development of preventive strategies in football.