Test-Retest Reliability and Usefulness of a Foot-Ankle Rebound-Jump Test for Measuring Foot-Ankle Reactive Strength in Athletes.

PURPOSE: This study investigated the test-retest reliability and usefulness of the foot-ankle rebound-jump test (FARJT) for measuring foot-ankle reactive strength metrics in athletes. METHODS: Thirty-six highly trained, healthy athletes (5 female; 21.5 [3.9] y; 1.80 [0.10] m; 72.7 [10.4] kg) performed 8 repeated bilateral vertical foot-ankle rebound jumps on 2 testing days. Testing days were 1 week apart, and these sessions were preceded by a familiarization session. Reactive strength metrics were calculated by dividing jump height (in meters) by contact time (in seconds) for the reactive strength index (RSI) and flight time (in seconds) by contact time (in seconds) for the reactive strength ratio (RSR). The mean of 4 jumps (excluding the first and last 2 jumps) on each testing session were considered for RSI and RSR reliability and usefulness analysis. RESULTS: We found a high reliability of the FARJT for RSI (intraclass correlation coefficient [ICC] > .90 and coefficient of variation [CV] = 12%) and RSR (ICC ≥ .90 and CV = 8%). Regarding their usefulness, both RSI and RSR were rated as "marginal" in detecting the smallest worthwhile change (typical error > smallest worthwhile change) and "good" in detecting a moderate change in performance. CONCLUSIONS: The results showed that a FARJT is a highly reliable test for measuring foot-ankle reactive strength in athletes and useful for quantifying changes, for example, following a training block. However, its usefulness as an accurate daily or weekly monitoring tool in practice is questionable.

Human foot muscle strength and its association with sprint acceleration, cutting and jumping performance, and kinetics in high-level athletes.

The primary objective of this study was to investigate the relationship between metatarsophalangeal joint (MTPj) flexion torque and sprint acceleration, cutting and jumping performance, and kinetics. A secondary aim was to explore this relationship when MTP flexion strength was associated with other foot and lower limb neuromuscular outputs. After an initial MTPj flexion torque assessment using a custom-built dynamometer, 52 high-level athletes performed the following tasks on a force platform system: maximal sprint acceleration, 90-degree cutting, vertical and horizontal jumps, and foot-ankle hops. Their foot posture, foot passive stiffness and foot-ankle reactive strength were assessed using the Foot Posture Index, the Arch Height Index Measurement System and the Foot-Ankle Rebound Jump Test. Ankle plantarflexion and knee extension isometric torque were assessed using an isokinetic dynamometer. During maximal speed sprinting, multiple linear regressions suggested a major contribution of MTPj flexion torque, foot passive stiffness and foot-ankle reactive strength to explain 28% and 35% of the total variance in the effective vertical impulse and contact time. Ankle plantarflexor and quadriceps isometric torques were aggregately contributors of acceleration performance and separate contributors of cutting and jumping performance. In conclusion, MTPj flexion torque was more strongly associated with sprinting performance kinetics especially at high-speed.

Overuse injury and affects in competitive sport: A prospective longitudinal study.

Overuse injuries, which have a high prevalence in sport, are suggested to result in different affective responses in comparison to traumatic injuries. Affects may also reciprocally act as risk factors for overuse injury. The aim of this study was to examine the associations between overuse injury and affects within a longitudinal follow-up design. Competitive athletes (N = 149) of various sports and levels of competition completed the Positive and Negative Affect Schedule (PANAS) and the Oslo Sports Trauma Research Centre Overuse injury questionnaire (OSTRC-O) once a week over 10 consecutive weeks. Bivariate unconditional latent curve model analyses with structured residuals were performed to evaluate the associations within and across weeks between OSTRC-O severity score and affects. Results indicated that OSTRC-O severity score and positive affects (PA) had a statistically significant negative within-week relation (r = -24.51, 95% CI = [-33.9, -15.1], p < 0.001). Higher scores of overuse injury were significantly related to lower levels of PA across weeks (ß = -0.02, 95% CI = [-0.04, -0.001], p = 0.044), while the reciprocal effect of PA on overuse injury was not significant (ß = -0.13, 95% CI = [-0.52, 0.26], p = 0.51). No statistically significant association was observed between OSTRC-O severity score and negative affects, neither within nor across weeks. Our findings suggest that overuse injury may have adverse psychological consequences on the long run through lessened PA and address the need for providing sustainable psychological support focusing upon such PA when working with athletes experiencing overuse injury.

Is it time to develop specific return to running criteria for ACL rehabilitation? An international survey of physiotherapists criteria for return to running following ACL injury.

OBJECTIVE: To determine return to running criteria currently used by physiotherapists following anterior cruciate ligament (ACL) injury. DESIGN: Self-reported online international survey. METHODS: An online survey of physiotherapists across Australia, the Netherlands and France. RESULTS: A total of 476 respondants participated in the survey across Australia (n = 153), the Netherlands (n = 162), and France (n = 161). For return to running criteria following a non-operative approach, the majority of respondents chose swelling (40.55%, n = 193/476), pain (38.24%, n = 182/476), knee extensor strength (34.34%, n = 163/476), single leg squat (31.93%, n = 152/476) and knee flexor strength (29.83%, n = 142/476). After ACL reconstruction, the highest responses were also swelling (41.18%, n = 196/476), pain (37.18%, n = 177/476), knee extensor strength (37.18%, n = 177/476) and single leg squat (33.19%, n = 158/476). From the identified themes the most common cutoff variables were pain between 0 and 3/10, swelling < grade 1+ and limb symmetry on strength and hop tests >70 %. CONCLUSION: Physiotherapists in Australia, France, and the Netherlands use many different return to running criteria and most of them use more than one criterion. Despite this, there was little consensus on the cut-off physiotherapists use to apply these criteria.

Muscle injuries in athletics during the 2020 Tokyo Olympic Games: differences between heats and finals.

BACKGROUND: The aim of this study was to analyze muscle injuries and their related risk factors during the Athletics events of the 2020 Tokyo Olympic Games including the differences in muscle injury rates between heats and finals. METHODS: We included and analyzed in this study muscle injuries diagnosed by either magnetic resonance imaging, ultrasound, or physical examinations by at least two physicians, from Athletics athletes participating at the 2020 Tokyo Olympic Games. Data from electronic medical records, including sex, nationality, event, and the round (heat vs. final) during which the muscle injury occurred and the air temperature in the stadium, measured every five minutes during the competition were extracted. RESULTS: Among the 1631 athletes who competed, a total of 36 athletes (20 males and 16 females) were diagnosed with a muscle injury during the 2020 Tokyo Olympic Games. Among them, 24 occurred during heats (1.47 per 100 athletes) and 12 during finals (2.20 per 100 athletes) (P=0.25). Logistic regression analysis revealed that the geographic region of athletes' origin was a factor associated with muscle injury, with the highest muscle injury rate being in athletes from Africa (odds ratio [OR]=4.74, 95% confidence interval [CI]) = 1.75 to 12.82) and North America (OR=3.02, 95%CI=1.27 to 7.20). For male athletes, competing in finals was a risk factor to sustain a muscle injury (OR=2.55, 95%CI=1.01 to 6.45). CONCLUSIONS: During the 2020 Olympic Games, muscle injury rate was higher in finals than in heats, reaching statistical significance in male athletes.

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.

How do sports injury epidemiological outcomes vary depending on athletes' response rates to a weekly online questionnaire? An analysis of 39-week follow-up from 391 athletics (track and field) athletes.

OBJECTIVE: To explore how sports injury epidemiological outcomes (i.e., prevalence, average prevalence, incidence, burden, and time to first injury) vary depending on the response rates to a weekly online self-reported questionnaire for athletes. METHODS: Weekly information on athletics injuries and exposure from 391 athletics (track and field) athletes was prospectively collected over 39 weeks (control group of the PREVATHLE randomized controlled trial) using an online self-reported questionnaire. The data were used to calculate sports injury epidemiological outcomes (i.e., prevalence, average prevalence, incidence, burden, and time to first injury) for sub-groups with different minimum individual athletes' response rates (i.e., from at least 100%, at least 97%, at least 95%, … to at least 0% response rate). We then calculated the relative variation between each sub-group and the sub-group with a 100% response rate as a reference. A substantial variation was considered when the relative variation was greater than one SD or 95% CI of the respective epidemiological outcome calculated in the sub-group with a 100% response rate. RESULTS: Of 15 249 expected weekly questionnaires, 7209 were completed and returned, resulting in an overall response rate of 47.3%. The individual athletes' response rates ranged from 0% (n = 51) to 100% (n = 100). The prevalence, average weekly prevalence, and time to first injury only varied substantially for the sub-groups below a 5%, 10% and 18% minimum individual response rate, respectively. The incidence and injury burden showed substantial variations for all sub-groups with a response rate below 100%. CONCLUSIONS: Epidemiological outcomes varied depending on the minimum individual athletes' response rate, with injury prevalence, average weekly prevalence, and time to first injury varying less than injury incidence and injury burden. This highlights the need to take into account the individual response rate when calculating epidemiological outcomes, and determining the optimal study-specific cut-offs of the minimum individual response rate needed.

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.

Injuries and illnesses at the Munich 2022 European Championships: a prospective study of 5419 athletes from 52 countries involved in 9 sports.

Objective: To describe the incidence and characteristics of the sports injuries and illnesses that occurred during the 2022 European Championships. Methods: We conducted a prospective study on newly incurred injuries and illnesses collected by the national medical teams and the local organising committee physicians using a standardised online report form on a daily basis, in all athletes registered at the 2022 European Championships from 11 August 2022 to 21 August 2022 in Munich (Germany). Results: In total, 5419 athletes were registered at the 2022 European Championships in 9 sports. A total of 181 in-competition injuries were reported, representing an overall incidence of 33.4 injuries per 1000 registered athletes, with higher values in triathlon, cycling and athletics. More injuries located at the lower limb and involving the muscles and skin were reported in athletics, at the lower limb and involving the skin in triathlon, at the head and trunk and upper limb and involving head and skin in cycling. A total of 65 illnesses were reported, representing an overall incidence of 12.0 illnesses per 1000 registered athletes, with higher values in athletics and rowing. The most affected common system was the cardiovascular system (24.6%), followed by the gastrointestinal (18.5%) and upper respiratory tracts (16.9%). The most frequent causes were exercise (36.9%), infections (30.8%) and 'others' (10.8%). Conclusion: This was the first injury and illness surveillance during multisports European Championships providing relevant results to help anticipate medical services and athletes' health protection, and highlighting the need for special attention for triathlon and cycling.

Athletes who have already experienced an injury are more prone to adhere to an injury risk reduction approach than those who do not: an online survey of 7870 French athletics (track and field) athletes.

Objective: To compare the perception towards injury risk reduction approach between athletes who have already experienced an injury and those who have not. Methods: We conducted a cross-sectional study using a one-time online survey asking athletics athletes licensed at the French Federation of Athletics (http://www.athle.fr) about their perceptions regarding injuries and injury risk reduction behaviours. We statistically compared athletes who already experienced an injury and those who did not. Results: A total of 7870 athletes were included. 90% of athletes declared having experienced at least one injury. They (1) were proportionally more men than women, (2) had significantly more years of experience in athletics, (3) had a significant difference in disciplines (more hurdles, jumps and combined events and fewer sprint athletes), (4) had a significant difference in competition levels (more national and less departmental levels) and (5) reported significantly higher values or agreements in favour of injury risk reduction approach, compared with uninjured athletes. There were significantly more athletes declaring following injury risk reduction programmes among athletes who experienced at least one injury than those who did not. Conclusions: Athletes who experienced at least one injury during their lifetime were more prone to adhere to injury risk reduction strategies than athletes who have never experienced an injury. Their entourage (coaches and health professionals) should use this fertile ground to implement injury risk reduction strategies. In addition, their experience should be disseminated to uninjured athletes to help them adhere to injury risk reduction without injury experience.

Perceptions and beliefs on sports injury prediction as an injury risk reduction strategy: An online survey on elite athletics (track and field) athletes, coaches, and health professionals.

OBJECTIVES: To explore perceptions and beliefs of elite athletics (track and field) athletes, coaches, and health professionals, towards the use of injury prediction as an injury risk reduction strategy. DESIGN: Cross-sectional study. METHOD: During the 2022 European Athletics Championships in Munich, registered athletes, coaches, and health professionals were asked to complete an online questionnaire on their perceptions and beliefs of injury prediction use as an injury risk reduction strategy. The perceived level of interest, intent to use, help, potential stress (psychological impact) and dissemination were assessed by a score from 0 to 100. RESULTS: We collected 54 responses from 17 countries. Elite athletics stakeholders expressed a perceived level of interest, intent to use, and help of injury prediction of (mean ± SD) 85 ± 16, 84 ± 16, and 85 ± 15, respectively. The perceived level of potential stress was 41 ± 33 (range from 0 to 100), with an important inter-individual variability in each elite athletics stakeholder's category. CONCLUSIONS: This was the first study investigating the perceptions and beliefs of elite athletics stakeholders regarding the use of injury prediction as an injury risk reduction strategy. Regardless of the stakeholders, there was a high perceived level of interest, intent to use and help reported in this potential strategy.

Understanding the first injury in athletics and its effect on dropout from sport: an online survey on 544 high-level youth and junior athletics (track and field) athletes.

Objective: To describe the first injury and to investigate whether it plays a role in altering athletics' sustainable practice. Methods: We conducted a cross-sectional study using an exploratory survey on the first injury and its consequences on athletics practice. In 2021, we asked all high-level athletes licensed with the French Federation of Athletics (FFA) under 18 years, under 20 years and under 23 years categories between 2007 and 2021. Results: Out of 6560 emails sent by FFA, 544 athletes responded, and 93.6% (n=510) reported experiencing at least one injury during their career. The first injury occurred at a mean age of 17.5±3.3 years after 6.1±4.1 years of athletics practice. The main locations of the first injury were the posterior thigh (28.9%), the ankle (16.5%) and the knee (12.6%), and the principal reported injury types were muscle (37.7%), tendon (17.5%) and ligament (15.5%). More than a third of injured athletes (36.7%) reported experiencing ongoing symptoms or sequelae after their first injury, and about half (48.5%) experienced recurrences. About 20% had stopped athletics at the time of the survey, with injury problems the primary cause of athletes dropping out (46.2%), including the first injury (9.4%). Conclusions: Injuries played an important role in altering sustainable athletics practice, with injury accounting for about 50% of all reported dropouts and the first injury accounting for about 10% of all reported causes. Our results provide evidence to target the prevention of the first injury, which could be considered the origin of the 'vicious circle' of injuries.

Current warm-up practices before maximal sprinting in track-and-field (athletics).

BACKGROUND: Warm-up is commonly performed by track-and-field athletes before performing maximal sprinting activities. Whilst some warm-up strategies may enhance athletes' physical and mental readiness, less is known about the current athletes' behaviors and warm-up practices in track and field. Therefore, this study aimed to identify the warm-up practices in a population of athletes performing in sprinting disciplines. METHODS: A cross-sectional exploratory study was performed in which track-and-field athletes, performing in athletics at a competitive level in disciplines requiring maximal acceleration and sprinting were recruited. We collected, using an online survey, information about 1) "General and Anthropometric data;" 2) "Athletics training practices" questioning the level of practices and the training frequency; and 3) "Athletics warm-up practices before maximal sprinting" questioning warm-up structure, duration and specific content. RESULTS: A total of 114 athletes replied to the survey. They reported a mean weekly training duration of 10.5 (±4.0) hours and a pre-maximal sprint warm-up duration of 40.5 (±13.5) minutes. During warm-up, they were engaged in five principal activities: predominantly moderate jogging (95% participation, 8±3.3 minutes), succeeded by dynamic and/or ballistic stretching (78% participation, 9±4.3 minutes), followed by athletic drills (96% participation, 15±5.4 minutes), culminating in accelerations (100% participation) along with high-speed running (77% participation). Warm-up duration and composition differed across athletes' levels of practice and disciplines. CONCLUSIONS: Most of the participants' warm-up practices were typically structured in a three-phase manner, comprising jogging, stretching, and specific training (athletic drills and accelerations). Most athletes followed scientific-based warm-up recommendations there are some areas where the evidence is limited, and more research is needed to determine the optimal warm-up routine for athletes.

Risk factors for injury complaints leading to restricted participation in Athletics (Track and Field): a secondary analysis of data from 320 athletes over one season.

Objective: To investigate if several potential risk factors were associated with time to injury complaints leading to participation restriction in Athletics (ICPR). Methods: We performed a secondary analysis of data collected during 39 weeks of the 2017-2018 Athletics season in a cluster-randomised controlled trial ('PREVATHLE'). Univariate and multivariable analyses using Cox regression models were performed to analyse the association between the time to first ICPR and potential risk factors collected (1) at baseline: sex, age, height, body mass, discipline, the usual duration of Athletics training and non-specific sports training, ICPR in the preceding season (yes/no), ICPR at baseline (yes/no); (2) weekly during the season: duration and intensity of Athletics training and competition, and non-specific sports training, fitness subjective state, sleep duration and illness (yes/no); and (3) combined. Results: Data from 320 athletes were included; 138 (43.1%) athletes reported at least one ICPR during the study follow-up. The combined multivariable analyses revealed that the risk of ICPR at any given time was significantly higher in athletes with a pre-existing ICPR (hazard rate ratio, HRR 1.90, 95% CI 1.15 to 3.15; p=0.012) and lower in athletes with a higher fitness subjective state (HRR 0.63, 95% CI 0.55 to 0.73; p<0.001) and who had had at least one illness during the season (HRR 0.42, 95% CI 0.29 to 0.62; p<0.001). Conclusions: Our results provide new insights into injury risk factors in Athletics that could help with potential injury risk reduction strategies. These could be to explore the pre-existing injury presence at the season's beginning and to monitor the fitness subjective state and illnesses occurrence during the season. Trial registration: ClinicalTrials.gov Identifier: NCT03307434.

Epidemiology of injuries in elite Women's Artistic Gymnastics: a retrospective analysis of six seasons.

Background: Women's Artistic Gymnastics (WAG) is a sport well known for requiring a heavy and difficult training load from a younger age to reach a high level of performance. This also is associated with an injury risk. Epidemiological studies are thus needed to improve injury prevention strategies. Objective: We aimed to determine the injury epidemiology in French high-level WAG. Methods: We conducted a retrospective analysis of injury data collected prospectively over six seasons from the 2014-2015 season to the 2019-2020 season among French high-level Women's Artistic Gymnasts from the France Gymnastics National Centre of Saint-Etienne. We performed descriptive analyses, including the calculation of the 1-year injury prevalence. Results: 43 gymnasts were included in this study, representing 111 gymnast-seasons. A total of 285 injuries were collected over the study period, that was, an average of 2.6 injuries per gymnast per season. On average, 91.4% of gymnasts had at least one injury per season. The estimated injury incidence rate was 1.8 injuries per 1000 hours of gymnastics practice. The knee was the most affected joint (16%), followed by the elbow (12%) and the ankle (12%). The most frequent injury type was physis pathologies (16%) and bone injuries (15%). Eighty-eight per cent of injuries required a modification of the gymnastics practice. Conclusions: The results of this study allowed a description of the epidemiology of injuries in this population of young and elite gymnasts. This very high injury prevalence supports the need to improve injury risk reduction strategies in WAG.

Traumatic muscle injury.

Traumatic muscle injury represents a collection of skeletal muscle pathologies caused by trauma to the muscle tissue and is defined as damage to the muscle tissue that can result in a functional deficit. Traumatic muscle injury can affect people across the lifespan and can result from high stresses and strains to skeletal muscle tissue, often due to muscle activation while the muscle is lengthening, resulting in indirect and non-contact muscle injuries (strains or ruptures), or from external impact, resulting in direct muscle injuries (contusion or laceration). At a microscopic level, muscle fibres can repair focal damage but must be completely regenerated after full myofibre necrosis. The diagnosis of muscle injury is based on patient history and physical examination. Imaging may be indicated to eliminate differential diagnoses. The management of muscle injury has changed within the past 5 years from initial rest, immobilization and (over)protection to early activation and progressive loading using an active approach. One challenge of muscle injury management is that numerous medical treatment options, such as medications and injections, are often used or proposed to try to accelerate muscle recovery despite very limited efficacy evidence. Another challenge is the prevention of muscle injury owing to the multifactorial and complex nature of this injury.