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.

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.

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.

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.

Elite vs. Experienced Male and Female Trail Runners: Comparing Running Economy, Biomechanics, Strength, and Power.

ABSTRACT: Besson, T, Pastor, FS, Varesco, G, Berthet, M, Kennouche, D, Dandrieux, P-E, Rossi, J, and Millet, GY. Elite vs. experienced male and female trail runners: comparing running economy, biomechanics, strength, and power. J Strength Cond Res 37(7): 1470-1478, 2023-The increased participation in trail running (TR) races and the emergence of official international races have increased the performance level of the world best trail runners. The aim of this study was to compare cost of running (Cr) and biomechanical and neuromuscular characteristics of elite trail runners with their lower level counterparts. Twenty elite (10 females; ELITE) and 21 experienced (10 females; EXP) trail runners participated in the study. Cr and running biomechanics were measured at 10 and 14 km·h-1 on flat and at 10 km·h-1 with 10% uphill incline. Subjects also performed maximal isometric voluntary contractions of knee and hip extensors and knee flexors and maximal sprints on a cycle ergometer to assess the power-torque-velocity profile (PTVP). Athletes also reported their training volume during the previous year. Despite no differences in biomechanics, ELITE had a lower Cr than EXP (p < 0.05). Despite nonsignificant difference in maximal lower-limb power between groups, ELITE displayed a greater relative torque (p < 0.01) and lower maximal velocity (p < 0.01) in the PTVP. Females displayed shorter contact times (p < 0.01) compared with males, but no sex differences were observed in Cr (p > 0.05). No sex differences existed for the PTVP slope, whereas females exhibited lower relative torque (p < 0.01) and velocity capacities (p < 0.01) compared with males. Although not comprehensively assessing all determining factors of TR performance, those data evidenced level and sex specificities of trail runners in some factors of performance. Strength training can be suggested to lower level trail runners to improve Cr and thus TR performance.

Relationship between a daily injury risk estimation feedback (I-REF) based on machine learning techniques and actual injury risk in athletics (track and field): protocol for a prospective cohort study over an athletics season.

INTRODUCTION: Two-thirds of athletes (65%) have at least one injury complaint leading to participation restriction (ICPR) in athletics (track and field) during one season. The emerging practice of medicine and public health supported by electronic processes and communication in sports medicine represents an opportunity for developing new injury risk reduction strategies. Modelling and predicting the risk of injury in real-time through artificial intelligence using machine learning techniques might represent an innovative injury risk reduction strategy. Thus, the primary aim of this study will be to analyse the relationship between the level of Injury Risk Estimation Feedback (I-REF) use (average score of athletes' self-declared level of I-REF consideration for their athletics activity) and the ICPR burden during an athletics season. METHOD AND ANALYSIS: We will conduct a prospective cohort study, called Injury Prediction with Artificial Intelligence (IPredict-AI), over one 38-week athletics season (from September 2022 to July 2023) involving competitive athletics athletes licensed with the French Federation of Athletics. All athletes will be asked to complete daily questionnaires on their athletics activity, their psychological state, their sleep, the level of I-REF use and any ICPR. I-REF will present a daily estimation of the ICPR risk ranging from 0% (no risk for injury) to 100% (maximal risk for injury) for the following day. All athletes will be free to see I-REF and to adapt their athletics activity according to I-REF. The primary outcome will be the ICPR burden over the follow-up (over an athletics season), defined as the number of days lost from training and/or competition due to ICPR per 1000 hours of athletics activity. The relationship between ICPR burden and the level of I-REF use will be explored by using linear regression models. ETHICS AND DISSEMINATION: This prospective cohort study was reviewed and approved by the Saint-Etienne University Hospital Ethical Committee (Institutional Review Board: IORG0007394, IRBN1062022/CHUSTE). Results of the study will be disseminated in peer-reviewed journals and in international scientific congresses, as well as to the included participants.

Elite Road vs. Trail Runners: Comparing Economy, Biomechanics, Strength, and Power.

ABSTRACT: Sabater Pastor, FS, Besson, T, Berthet, M, Varesco, G, Kennouche, D, Dandrieux, P-E, Rossi, J, and Millet, GY. Elite road vs. trail runners: comparing economy, biomechanics, strength, and power. J Strength Cond Res 37(1): 181-186, 2023-The purpose of this study was to determine the differences between road (ROAD) vs. trail (TRAIL) elite runners in terms of force-velocity profile (FVP), running biomechanics, lower-limb maximal isometric strength, cost of running (Cr), and training. Seventeen male elite athletes (10 TRAIL and 7 ROAD) participated in this study. Force-velocity profile was measured using a 2-sprint test on a cycle ergometer. Strength was assessed with a dynamometer measuring isometric maximum voluntary torque of the knee extensors and knee flexors. Biomechanics parameters (running kinematics and stiffness) were measured, and Cr was calculated at 10 and 14 km·h-1 at 0% slope and at 10 km·h-1 on a 10% slope on a treadmill. Athletes also reported their training duration during the previous year. Theoretical maximal torque (F0) and maximal power (Pmax) in the FVP were higher for TRAIL vs. ROAD (122 ± 13 vs. 99 ± 7 N·m, p = 0.001; and 726 ± 89 vs. 626 ± 44 W; p = 0.016). Cost of running was higher for TRAIL compared with ROAD on flat at 14 km·h-1 (4.32 ± 0.22 vs. 4.06 ± 0.29 J·kg-1·m-1; p = 0.047) but similar at 10 km·h-1 and uphill. No differences were found in maximal isometric strength or running biomechanics. ROAD spent 81% more time training than TRAIL (p = 0.0003). The specific training (i.e., "natural" resistance training) performed during graded running in trail runners and training on level surface at high speed may explain our results. Alternatively, it is possible that trail running selects stronger athletes because of the greater strength requirements of graded running.