The Effect of Blood Flow Restriction during Low-Load Resistance Training Unit on Knee Flexor Muscle Fatigue in Recreational Athletes: A Randomized Double-Blinded Placebo-Controlled Pilot Study.

Background/Objectives: Despite the growing popularity of training with a controlled form of vascular occlusion, known as blood flow restriction (BFR) training, in the rehabilitation of orthopedic patients and sports medicine, there remains ample space for understanding the basis of its mechanism. The pilot study assessed the effect of BFR during a low-load resistance training unit on knee flexor muscle fatigue, intending to decide whether a larger trial is needed and feasible. Methods: The study used a prospective, randomized, parallel, double-blind, placebo-controlled design. Fifteen male healthy recreational athletes were randomly assigned to three equal groups: BFR Group, Placebo Group, and Control Group. The primary outcome was the change in the surface electromyography-based (sEMG-based) muscle fatigue index, which was determined by comparing the results obtained before and after the intervention. The intervention was the application of BFR during low-load resistance training for knee flexors. The occurrence of any adverse events was documented. Results: In all groups, the sEMG-based fatigue index for semitendinosus and biceps femoris muscles decreased after low-load resistance training, with the largest decrease in the BFR group. Although not statistically significant, BFR showed moderate and large effect sizes for the fatigue index of semitendinosus and biceps femoris, respectively. No adverse events were noted. Conclusions: The pilot study suggested that BFR during a low-load resistance training unit might affect knee flexor muscle fatigue, supporting the development of a larger randomized clinical trial.

Coverage from medical teams and injury/illness epidemiology within youth athletics in Africa: A prospective study during the 2023 African Youth Under 18/20 Athletics Championships.

OBJECTIVES: To describe athletes' coverage by national medical teams, and injuries and illnesses occurring during the four weeks before and during the 2023 African Youth Under 18/20 Athletics Championships. DESIGN: Cross-sectional and prospective cohort study design. METHODS: We conducted a study with data collection of: 1) national medical teams, 2) injury and illness complaints during the four weeks preceding the championships using an online pre-participation health questionnaire, and 3) newly incurred in-championship injuries and illnesses collected by national medical teams and the local organising committee using daily standardised online report forms, for all registered athletes at the championships. RESULTS: Among the 43 countries participating at the championships, 15 (34.9 %) countries had a medical team with at least one medical personnel. Of the 15 countries, 6 (40.0 %) countries had at least one physiotherapist and one physician, 4 (26.7 %) countries had only physiotherapist(s), and 5 (33.3 %) countries had only physician(s). Nine (60 %) countries participated in the injury surveillance study, including 397 athletes: 61 (15.4 %) completed the pre-participation health questionnaire and 11 athletes (18.0 %) reported an injury complaint and 6 (9.8 %) an illness complaint during the four weeks before the championships. During the championships, there were 52.9 injuries and 50.4 illnesses per 1000 registered athletes. The main injury location was the thigh (33.3 %), and the main injury type was the muscle (47.6 %). The most common system affected by illness was the upper respiratory tract (55.0 %), and the main illness cause was idiopathic (50.0 %). CONCLUSIONS: This preliminary study provides foundational information to improve medical coverage and services during international championships, and orient injury/illness prevention in youth athletics across Africa.

Single-legged landing behavior of high school basketball players with chronic ankle instability.

OBJECTIVES: Anterior cruciate ligament injury is one of the most serious ligamentous injuries. The purpose is to compare the impact of the ankle joint on the knee during landing between athletes with chronic instability and a control group (coper group) and to verify the effects of the kinetic chain from other joints. DESIGN: Prospective study. SETTING: High school basketball. PARTICIPANTS: Participants were 62 female high school basketball players who had participated in team sports for >6 months. MAIN OUTCOME MEASURES: Player joint angles, movements, and moments. RESULTS: The knee valgus moment was significantly higher in the chronic ankle instability group than in the coper group (20%-60% [p < 0.01]; 80%-100% [p < 0.05]) during landing motion. The knee valgus moment was also significantly higher during the change from the maximum knee joint flexion position to the maximum extension (p < 0.05). In addition, the landing motions of the chronic instability group may have utilized suboptimal compensatory motor strategy on the sagittal plane, depending heavily on the knee joint's abduction moment. CONCLUSIONS: Our findings indicate that the chronic ankle instability group uses a different landing strategy pattern than the coper group by changing the joint moment and joint angle during landing, which may increase the risk of anterior cruciate ligament injury.

Is the risk of muscle injuries higher in the finals than in previous rounds of the 100 m, 200 m and 400 m sprints of international athletics championships?

OBJECTIVES: To compare incidence rates of lower limb muscle injuries (LLMIs) and hamstring muscle injuries (HMIs) in 100 m, 200 m and 400 m sprints disciplines between finals, semi-finals and heats of international athletics championships. DESIGN: Prospective total population study. METHODS: We analysed in-competition LLMIs and HMIs of female and male athletes during eight championships between 2009 and 2022. RESULTS: LLMI and HMI incidence rates in 100 m finals were significantly higher than in heats and semi-finals for female and male athletes. HMI incidence rates were significantly higher in 200 m finals than heats and semi-finals for male athletes. CONCLUSIONS: LLMI and HMI risk was higher in finals compared to previous rounds during international athletics championships.

A sports-related injury prevention program for Dutch youth volleyball players: Process evaluation alongside a quasi-randomized controlled trial.

OBJECTIVE: This process evaluation aimed to gain insight into the implementation of the VolleyVeilig Youth program by Dutch volleyball clubs within the context of an effectiveness trial. METHODS: We applied the UK Medical Research Council framework for process evaluations and assessed the context, implementation and mechanisms of impact. Trainers participating in the effectiveness trial were asked to complete a questionnaire at the end of the study. A subsample of the trainers based on the self-reported adherence score was invited to participate in an interview accordingly. We used a thematic analysis to present the data. RESULTS: Thirty-one trainers (100%) completed the questionnaire, and seven agreed to participate in an interview. Although adherence gradually decreased over the volleyball season, most trainers reported partially adhere with the program until the end of the study. The main themes included factors associated with the (1) VolleyVeilig Youth program, (2) trainer, (3) players, and (4) volleyball club. CONCLUSION: Although (partial) adherence to the VolleyVeilig Youth program was high in this study, implementation strategies must be developed to target the barriers reported by the trainers before the program can be successfully implemented nationwide in the Netherlands.

Does Headgear Prevent Sport-Related Concussion? A Systematic Review and Meta-Analysis of Randomized Controlled Trials Including 6311 Players and 173,383 Exposure Hours.

CONTEXT: A sport-related concussion (SRC) is a traumatic brain injury that is caused by biomechanical stresses and results in a complex pathophysiological process in the brain. Some in the sporting community believe that headgear (HG) can prevent SRC, and several professional Australian sports organizations, including rugby, football, and soccer clubs, recommend its use. OBJECTIVE: The purpose of this study is to determine whether HG is effective in lowering the prevalence of SRC in sports. DATA SOURCES: A systematic search for related studies published between 1985 and 2023 was conducted using the following databases: Cochrane Library, AMED, PubMed, Web of Science, and Physiotherapy Evidence Database (PEDro). STUDY SELECTION: Only randomized controlled trials (RCTs) that investigated the effectiveness of HG in reducing SRC rate were included. STUDY DESIGN: Systematic review and meta-analysis of RCTs. LEVEL OF EVIDENCE: Level 1a. DATA EXTRACTION: Two researchers independently completed the title and abstract search and performed full-text reviews. A third reviewer was consulted to reach a consensus if any discrepancies were noted. The PEDro scale was used to evaluate the quality of the included RCTs. Data recorded from each study included authors, year of publication, type and number of players, study design, duration of the study, injury rate, compliance (%), sports/level, and exposure hours. RESULTS: The pooled results of 6311 players and 173,383 exposure hours showed 0% SRC reduction per 1000 hours of exposure in the experimental group compared with the control group, with an injury risk ratio of 1.03 (95% CI, 0.82-1.30; P = 0.79). CONCLUSION: This systematic review and meta-analysis demonstrates that HG does not prevent SRC among soccer and rugby players, and therefore the findings from this meta-analysis do not currently support the use of HG to prevent SRC in soccer or rugby.

An Overview of Machine Learning Applications in Sports Injury Prediction.

Use injuries, i.e., injuries caused by repetitive strain on the body, represent a serious problem in athletics that has traditionally relied on historic datasets and human experience for prevention. Existing methodologies have been frustratingly slow at developing higher precision prevention practices. Technological advancements have permitted the emergence of artificial intelligence and machine learning (ML) as promising toolsets to enhance both injury mitigation and rehabilitation protocols. This article provides a comprehensive overview of recent advances in ML techniques as they have been applied to sports injury prediction and prevention. A comprehensive literature review was conducted searching PubMed/Medline, Institute of Electrical and Electronics Engineers (IEEE)/Institute of Engineering and Technology (IET), and ScienceDirect. Ovid Discovery and Google Scholar were used to provide additional aggregate results and a grey literature search. A focus was placed on papers published from 2017 to 2022. Algorithms of interest were limited to K-Nearest Neighbor (KNN), K-means, decision tree, random forest, gradient boosting and AdaBoost, and neural networks. A total of 42 original research papers were included, and their results were summarized. We conclude that given the current lack of open source, uniform data sets, as well as a reliance on dated regression models, no strong conclusions about the real-world efficacy of ML as it applies to sports injury prediction can be made. However, it is suggested that addressing these two issues will allow powerful, novel ML architectures to be deployed, thus rapidly advancing the state of this field, and providing validated clinical tools.

Towards the Development of a System Dynamics Model for the Prediction of Lower Extremity Injuries.

Acute noncontact Lower Extremity (LE) injuries constitute a significant problem in team sports. Despite extensive research, current knowledge on the risk factors of LE injuries is limited to static simplistic models of instantaneous cause and effect relationships ignoring the time dimension and the embedded complexity of LE injuries. Even though complex systems approaches have been used in various cases to improve policy and intervention effectiveness, there is limited research on predicting and managing LE injuries. This creates an opportunity to fill the gap in the current literature by applying the System Dynamics (SD) methodology to model LE injuries. The proposed approach allows for synthesizing risk factors and examining their interaction. This paper makes the first step towards such an approach by developing a causal loop model revealing the etiology of LE injuries. A causal loop model for LE injuries is developed via an extensive literature review and brainstorming with experts. In contrast to the traditional static approaches, the proposed model reveals some of the complexity and nonlinear relationships of the various sports injury risk factors. The derived causal loop model may then be used to quantify these interactions and develop a simulation model. This will be achieved by operationalizing and incorporating the main risk factors that impact LE injuries in an integrated sports injury prediction model. In this way, plausible strategies for preventing LE injuries can be tested prior implementation and thereby achieve optimization of intervention programs.

Data analysis of physical recovery and injury prevention in sports teaching based on wearable devices.

Athletes can also cause damage to some parts of their body during training, so specialized preparation activities should be carried out before athlete training to reduce the damage caused to the athlete's body, allowing the stressed parts to move and distribute the load. Excessive recovery has a significant effect on improving the performance level of the athletes studied and preventing sports injuries. This article studies the data analysis of body recovery and injury prevention in physical education teaching based on wearable devices. Real time collection of students' exercise data, including indicators such as exercise volume, heart rate, steps, distance, etc., by wearing wearable devices. By using Internet of Things technology to transmit data to cloud servers, data analysis and mining techniques are used to process the data and study issues related to body recovery and injury prevention. Specifically, this article adopts methods such as time series analysis, machine learning algorithms, and artificial neural networks to analyze the relationship between exercise data and body recovery and injury prevention, providing scientific guidance and support for physical education teaching. This method can monitor students' exercise data in real-time, predict the risk of physical recovery and injury, and provide corresponding prevention and guidance suggestions.

Shoulder muscle imbalance as a risk factor for shoulder injury in elite badminton players: A prospective study.

OBJECTIVES: To assess the impact of preseason shoulder testing on the risk of significant shoulder injury (SSI) in elite badminton players. DESIGN: Prospective cohort study. SETTING: Secondary care, academic medical center. PARTICIPANTS: Nineteen elite badminton players (19.37 ± 4.79 years, n = 13 males). MAIN OUTCOME MEASURES: At preseason, they had shoulder examination tests including the table-to-acromion distance and the glenohumeral rotation range of motion. The glenohumeral internal rotation deficit (GIRD) was calculated. Isokinetic internal and external rotator shoulder muscle strength was tested at 60°/s (concentric and eccentric modes) and 240°/s (concentric mode). Bilateral strength ratio (non-dominant:dominant) and unilateral agonist:antagonist conventional and functional ratios (FR: eccentric-to-concentric) were calculated. RESULTS: During the follow-up time of 38 weeks, SSIs were assessed by an experienced sport physician and 42% of the participants sustained at least one SSI at their dominant side. The preseason GIRD and FR at 240°/s (FR240) were independently associated with SSIs (G2 = 6.28, p = .012 and G2 = 6.23, p = .013, respectively). FR240 < 0.69 (odds ratio = 28.0) and GIRD> 14° (odds ratio = 36.14) were predictors for SSIs. CONCLUSIONS: Lower functional deceleration ratio and greater GIRD are associated with a higher risk of SSI at the dominant side in elite badminton players.

Motivation, injury prevention, and the incidence of sports injuries: A three-wave longitudinal test of self-determination theory.

This study applied self-determination theory (SDT) as a psychological framework to examine whether psychological need support and autonomous motivation are predictive of sports injury preventive behaviors and the incidence of sports injuries. 2042 secondary school students (mean age = 14.33, male = 44.3%) from China completed a survey of the study variables (using established scales) at three time points (baseline, 1-month follow-up, 3-month follow-up). Structural equation modeling examined the core tenets of SDT by testing if the change-scores of the SDT variables (i.e., psychological need support from PE teachers, students' motivation, and students' behavioral adherence) between baseline and 1-month follow-up, were predictive of sports injury incidence assessed at 3-month follow-up. Our model demonstrated acceptable goodness-of-fit parameters (CFI = 0.97, TLI = 0.96, RMSEA = 0.03, and SRMR = 0.05). The relationships between psychological need support, autonomous motivation, and behavioral adherence were both positive and significant. These SDT variables predicted the future incidence of sports injuries following the motivational pathways of SDT. Our study provides evidence of the predictive power of SDT variables on sports injury preventive behaviors and the incidence of sports injuries: Students who perceive their PE teachers as psychological need supportive possess higher autonomous motivation and behavioral adherence towards sports injury prevention, and are also less likely to encounter sports injuries in the future.

Having an injury complaint during the four weeks before an international athletics ('track and field') championship more than doubles the risk of sustaining an injury during the respective championship: a cohort study on 1095 athletes during 7 international championships.

OBJECTIVES: To analyse the association between pre-participation health status and in-championships injuries in a large dataset from seven international athletics championships, and to determine the health status of athletes during the four weeks before the start of international athletics championships. DESIGN: Prospective cohort study. METHODS: We used data collected from athletes of national teams with medical staff who participated i) in a pre-participation health survey (retrospective data collection) and ii) in an in-championships injury surveillance (prospective data collection) during seven international athletics championships (2013-2018). We performed a binomial logistic regression with in-championship injury (yes/no) as the dependent variable and sex, age, discipline (explosive/endurance), type of championships (outdoor/indoor) and pre-participation injury complaint (yes/no) and pre-participation illness complaint (yes/no) as independent variables, with odds ratios (OR) and 95% confidence intervals (95% CI). RESULTS: Out of the 1095 athletes included 31.2% reported an injury complaint during the 4 weeks before the championships and 21.6% an illness complaint. The univariate model showed that discipline, type of championships and pre-participation injury complaints (OR = 2.57, 95%CI: 1.66 to 3.97) were significantly associated with in-championships injuries, and the multivariable model showed that type of championships and pre-participation injury complaints (OR = 2.64, 95%CI: 1.60 to 4.36) remained significantly associated with in-championships injuries. CONCLUSIONS: Our present study shows that an injury complaint during the four weeks before an international athletics championship significantly increased risk of sustaining an injury during the following championship, which was reported by about one third of athletes with differences between sex and disciplines.

Relationships Between Performance and Injury Occurrence in Athletics (Track and Field): A Pilot Study on 8 National-Level Athletes From Sprints, Jumps and Combined Events Followed During at Least Five Consecutive Seasons.

Background: Performance success or failure in athletics (Track and Field) and the capacity to succeed are driven at the adult level, like in other sports, by many factors, injury being one of them. More information regarding the potential relationships between performance and injuries in athletics is needed. Objective: To analyse the potential association between performance and occurrence of injuries in national-level athletics athletes from sprints, jumps and combined events through several seasons. Methods: We performed a retrospective analysis of performance and injury data collected prospectively in 8 national-level athletics athletes followed during at least five consecutive seasons from 2009 to 2019. For each athlete, injuries data [total injuries (injuries) and time-loss injuries (TLI)] were collected by the same sports medicine physician throughout the study period using a medical attention injury definition. Performances during official competitions were collected on the French Federation of Athletics website, and included (i) any participation in national championships, (ii) any participation in an international competition (i.e., being national team member for an international competition), (iii) any podium at the national championships, (iv) any podium at an international competition, and (v) performance metrics normalised to the world record (WR) of the respective athletics speciality (%WR). For each athlete, we performed a descriptive analysis of the performances and injuries. We also performed four binomial logistic regressions with (1) national championships participation (yes/no) or (2) international competition participation (yes/no) as dependent variables, and injuries (yes/no) or TLI (yes/no) as independent variables, adjusted for individual athlete and number of seasons, and in models on participation in international competitions, was also adjusted for national championship participation (yes/no), with Odd Ratios (OR) with 95% confidence intervals (95%CI). Results: Among the 8 national-level athletics athletes included in the present study, cumulated 155 injuries, including 52 TLI (33.5%). There was an average of 2.7 ± 1.7 injuries and 0.9 ± 0.6 TLI per athlete per season over the study period. The occurrence of injuries was significantly associated with higher odds of national championships participation (OR = 4.85 [95% CI 3.10 to 3050.5], p = 0.021). The occurrence of TLI was significantly associated with higher odds of national championships participation (OR = 133.6 [95% CI 4.92 to 14251.5], p = 0.013). The occurrence of injuries or TLI were associated with insignificantly lower odds of international championships participation. Conclusions: Our present pilot study confirms that injuries are part of an athletes' life. The occurrence of at least one injury was associated with higher odds of participation in a national championship, whereas the absence of at least one injury was associated with higher odds of participation in an international championship. We hypothesised that the length of the season can play a role in the risk of injury occurrence, but if the athlete wants to reach his/her highest level, decreasing the risk of injuries seems to be of importance. Despite the caution that should be taken in the interpretation of our results, our present study confirms the interest and relevance of injury risk reduction approach in athletics.

The Epidemiology of Injuries in Spanish Rugby Union División de Honor.

BACKGROUND: We describe and analyze injury incidence, severity, cause of injury, anatomical location, damaged tissue, injury recurrence, and the time and place at which injuries occur over the course of a season. METHODS: An observational, descriptive, prospective, nomothetic, and multidimensional study was conducted during the 2018-2019 season with 258 players of the top semiprofessional rugby league in Spain (División de Honor de Rugby). Data were reported by the clubs' medical services. Reported time-loss injuries were collected. RESULTS: Overall exposure was 4100 h (137 matches), over 35 weeks of competition. A total of 288 injuries were reported, with three of these leading to withdrawal from the sport. A total average of 35.63 days was lost to injury. Overall time-loss injury incidence was 3.41 injuries/1000 h of exposure. Backs suffered 119 injuries corresponding to 3.80 injuries/1000 h of exposure, whilst forwards suffered 169 injuries with 4.27 injuries/1000 h of exposure. Severe injuries were the most frequent injury type. CONCLUSIONS: Outcomes confirm that more injuries take place during competition, with these also being more severe in nature. Contact injuries were most frequently suffered, above all, due to tackling or being tackled.

Effect of an Unsupervised Exercises-Based Athletics Injury Prevention Programme on Injury Complaints Leading to Participation Restriction in Athletics: A Cluster-Randomised Controlled Trial.

OBJECTIVE: To test the efficacy of the Athletics Injury Prevention Programme (AIPP) to reduce the percentage of athletes presenting at least one injury complaint leading to participation restriction (ICPR) over an athletics season. METHODS: During the 2017-2018 athletics season, we included in this cluster randomised controlled trial (ClinicalTrials.gov Identifier: NCT03307434) 840 athletes randomly assigned (randomisation unit: athletic clubs) to a control group (regular training) or to an intervention group (regular training plus the AIPP 2/week). Using a weekly online questionnaire, athletes reported the ICPR, training and competition exposures, and, for the intervention group, the compliance with the AIPP. The primary outcome was the percentage of athletes presenting at least one ICPR over the study follow-up. RESULTS: A total of 449 and 391 athletes were included in the intervention and control groups, respectively. From them, 68 (15.1%) and 100 (25.6%) athletes, respectively, provided 100% of the requested information during the follow-up (39 weeks). A total of 6 (8.8%) performed the AIPP 2/week or more. The proportion of athletes who had at least one ICPR over the follow-up period was similar in the intervention (64.7%) and control groups (65.0%), with adjusted odds ratios: 0.81 (95% CI 0.36 to 1.85). There were no between-group differences when comparing separately the subgroups corresponding with the different compliance levels. CONCLUSION: This cluster randomised controlled trial reported no efficacy of the AIPP. However, the overall response proportion and the compliance with the AIPP in the intervention group were low. In individual sports especially, efforts should be first made to improve the implementation and adoption of interventions.

Can We Go Online for Sports Injury Prevention? A Systematic Review of English-Language Websites with Exercise-Based Sports Injury Risk Reduction Programmes.

BACKGROUND: Preventing sports injuries is at the forefront of sports medicine. Although effective preventive strategies in scientific literature exist, their implementation is lagging behind. The Internet could support the translation of knowledge from the literature to end-users, but the quality of the online resources would have to be assured. This online-based systematic review is to assess availability, readability, quality, and content of the websites presenting exercise-based sports injury risk reduction (prevention) programmes. Moreover, the quality of reporting and contents of the exercise programmes were assessed. METHODS: Google, Yahoo, and Bing were searched on 2 September 2018. We used 'sports injury prevention program*' and 'sports injury prevention warm-up' as search phrases. The owners/authors of the included websites were asked for further recommendations on online resources. Search updates were run in DuckDuckGo on 15 May 2020 and 22 August 2021. Eligible websites were active, in English, and contained instructions for the exercise/s aiming at sports injury prevention. Two reviewers independently screened the links and previews and performed an in-depth appraisal of included websites. The website quality was assessed using JAMA framework criteria and Health on the Net Foundation Code of Conduct (HONcode) certification. The readability of websites was assessed using the Flesch-Kincaid Reading Ease score. The reporting appraisal of exercise programmes was done using the modified Consensus on Exercise Reporting Template (CERT). RESULTS: Among 480 websites screened, 16 were eligible with an additional four recommended and nine found in search updates (29 in total). None of the websites was certified by HONcode. The overall quality of websites was low 2.1 ± 1.0/4, but overall readability was high 67 ± 17/100. The average quality of reporting of exercise programmes was low 5.79 ± 3.1/12. Websites with community input had the lowest readability, but the highest quality, and vice versa websites run by businesses had the highest readability, but the lowest quality. Eight websites presented programmes tested for effectiveness. CONCLUSIONS: Overall, the quality of the websites was low, but their readability was high. Improvements required are relatively easy to implement (i.e. including the date when the website was updated, applying for HONcode certification) and extremely important (e.g. providing resources on which the website's content is based). There are some sports injury risk reduction programmes reported with high quality and effectiveness-tested available online for team sports, but none for individual sports. Trial Registration This review has been registered in the PROSPERO (CRD42019107104).

Low Horizontal Force Production Capacity during Sprinting as a Potential Risk Factor of Hamstring Injury in Football.

Clear decreases in horizontal force production capacity during sprint acceleration have been reported after hamstring injuries (HI) in football players. We hypothesized that lower FH0 is associated with a higher HI occurrence in football players. We aimed to analyze the association between sprint running horizontal force production capacities at low (FH0) and high (V0) velocities, and HI occurrence in football. This prospective cohort study included 284 football players over one season. All players performed 30 m field sprints at the beginning and different times during the season. Sprint velocity data were used to compute sprint mechanical properties. Players' injury data were prospectively collected during the entire season. Cox regression analyses were performed using new HI as the outcome, and horizontal force production capacity (FH0 and V0) was used at the start of the season (model 1) and at each measurement time point within the season (model 2) as explanatory variables, adjusted for individual players' (model 2) age, geographical group of players, height, body mass, and previous HI, with cumulative hours of football practice as the time scale. A total of 47 new HI (20% of all injuries) were observed in 38 out of 284 players (13%). There were no associations between FH0 and/or V0 values at the start of the season and new HI occurrence during the season (model 1). During the season, a total of 801 measurements were performed, from one to six per player. Lower measured FH0 values were significantly associated with a higher risk of sustaining HI within the weeks following sprint measurement (HR = 2.67 (95% CI: 1.51 to 4.73), p < 0.001) (model 2). In conclusion, low horizontal force production capacities at low velocity during early sprint acceleration (FH0) may be considered as a potential additional factor associated with HI risk in a comprehensive, multifactorial, and individualized approach.

Lower limb muscle injury location shift from posterior lower leg to hamstring muscles with increasing discipline-related running velocity in international athletics championships.

OBJECTIVE: To analyse the rates of lower limb muscle injuries in athletics disciplines requiring different running velocities during international athletics championships. DESIGN: Prospective total population study. METHODS: During 13 international athletics championships (2009-2019) national medical teams and local organizing committee physicians daily reported all newly incurred injuries using the same study design, injury definition and data collection procedures. In-competition lower limb muscle injuries of athletes participating in disciplines involving running (i.e. sprints, hurdles, jumps, combined events, middle distances, long distances, and marathon) were analysed. RESULTS: Among the 12,233 registered athletes, 344 in-competition lower limb muscle injuries were reported (36% of all in-competition injuries). The proportion, incidence rates and injury burden of lower limb muscles injuries differed between disciplines for female and male athletes. The most frequently injured muscle group was hamstring in sprints, hurdles, jumps, combined events and male middle distances runners (43-75%), and posterior lower leg in female middle distances, male long distances, and female marathon runners (44-60%). Hamstring muscles injuries led to the highest burden in all disciplines, except for female middle distance and marathon and male long distance runners. Hamstring muscles injury burden was generally higher in disciplines requiring higher running velocities, and posterior lower leg muscle injuries higher in disciplines requiring lower running velocities. CONCLUSIONS: The present study shows discipline-specific injury location in competition context. Our findings suggest that the running velocity could be one of the factors that play a role in the occurrence/location of muscle injuries.

Exercise-Based Injury Prevention in High-Level and Professional Athletes: Narrative Review and Proposed Standard Operating Procedure for Future Lockdown-Like Contexts After COVID-19.

In regular times, implementing exercise-based injury prevention programs into the training routine of high-level and professional athletes represents a key and challenging aspect to decrease injury risk. Barriers to implementing such prevention programs have previously been identified such as lack of resources, logistic issues or motivation. The COVID-19 pandemic associated with restrictions on daily life dramatically impacted sports participation from training to competition. It is therefore reasonable to assume that such lockdown-like context has exacerbated the challenge to implement exercise-based injury prevention programs, potentially leading to a greater musculoskeletal injury risk. In this narrative review, recommendations are proposed for building an expertise- and evidence-based Standard Operating Procedure for injury prevention in lockdown-like contexts for high-level and professional athletes. The following recommendations can be provided: (1) assess the global and sport-specific risks in the light of the ongoing cause of isolation; (2) adapt remote training materials and programs; (3) ensure regular quality communication within the staff, between athletes and the staff as well as between athletes; (4) follow the athlete's mental well-being; and (5) plan for a safe return-to-sports as well as for an ongoing monitoring of the load-recovery balance. These key domains should further be addressed to comply with local policies, which are subject to change over time in each individual country. The use of these recommendations may improve the readiness of athletes, coaches, physicians and all sports stakeholders for future lockdown-like contexts.