Purpose: The tethered swimming test is relevant for the longitudinal monitoring of swimmers. However, for accurate interpretation of observed variations over time, understanding the reliability of the test and the factors influencing it is crucial. This study aimed to assess the absolute and relative reliability of parameters derived from 10- and 30-second front-crawl-tethered swimming tests by considering swimming specialty, sex, and performance level. Output variables resulting from manual stroke cycle segmentation were examined to evaluate interevaluator reliability. Methods: Twenty-one highly trained swimmers performed the 2 specific time-based tests over 3 consecutive days. Relative and absolute reliability were assessed using the intraclass correlation coefficient and standard error of measurement, respectively. Results: Mean force, peak force, and impulse demonstrated high reliability (intraclass correlation coefficient > .86 and .73 for 10- and 30-s tests, respectively). Fatigue index, performance decrement, and rate of performance decline exhibited varying reliability from poor to high. These results were unaffected by swimming specialty, sex, performance level, or evaluator. Conclusion: The findings indicate that 10- and 30-second front-crawl tethered swimming tests are highly reliable. Mean force, peak force, and impulse emerge as the most reliable parameters, regardless of the swimming specialty, sex, performance level, or evaluator.
Empowered by technological progress, sports teams and bookmakers strive to understand relationships between player and team activity and match outcomes. For this purpose, the probability of an event to succeed (e.g., the probability of a goal to be scored, namely, xG for eXpected Goals) provides insightful information on team and player performance and helps statistical and machine learning approaches predict match outcomes. However, recent approaches require powerful but complex models that need more inherent interpretability for practitioners. This study uses a Bayesian generalized linear mixed-effects model to introduce a simple and interpretable xG modeling approach. The model provided similar performance when compared to the StatsBomb model (property of the StatsBomb company) using only seven variables relating to shot type and position, and surrounding opponents (AUC = 0.781 and 0.801, respectively). Pre-trained models through transfer learning are suitable for identifying teams’ strengths and weaknesses using small sample sizes and enable interpretation of the model’s predictions.
This article describes an evidence-informed, collaborative process to bridge the gap between science and practice and tailor representative training designs to a national water polo team. Team gaps and context-specific needs were identified and probed using quantitative methods and "gamestorming" focus groups. The resulting data informed the subsequent co-design of a Constraints-led Holistic Approach to Overcoming Stressors (CHAOS), an intervention that considered not only physical but also cognitive and emotional demands of competitive match play. The process we depict may be adapted to diverse contexts, and we additionally share practical tools and reflections that may be relevant for other scientist-practitioners.
Purpose:To report the prevalence of hip pain in elite badminton players, describe their hip pathologies, and evaluate expectations regarding hip pain. Patients and Methods:All badminton players registered at the national sports institute (Institut national du sport, de l'expertise et de la performance; INSEP) in France on 01/09/2023 were contacted by the medical team to complete a questionnaire comprising training information, prevalence of hip pain, and expectations regarding hip pain. The medical database was reviewed to identify all hip pathologies recorded. Results:Of the 20 elite badminton players registered at the national sports institute (10 females and 10 males, aged 23.8±3.9 years), 9 (45%) reported experiencing hip pain while registered at the institute, 4 at their dominant side only and 5 bilaterally. Six players had cam-type femoroacetabular impingement (FAI), concomitant with coxofemoral chondropathy and/or muscle tears in 3 athletes (requiring femoroplasty in 3). Furthermore, 3 more players had coxofemoral chondropathy and/or muscle tears. Before playing badminton at a high-level, 12 (60%) thought that becoming elite players could cause joint pain; however, none (0%) thought that it would cause pain specifically at their hip joint. Conclusion:Nine of 20 elite badminton players have experienced hip pain while registered at a national sports institute, with the most common hip pathologies being cam-type FAI (n=6; 30%) and muscle tears (n=4; 20%). Although before playing badminton at a high-level, none of the athletes thought that becoming an elite badminton player could cause pain specifically at the hip joint, at the time of the questionnaire, 19 athletes (95%) thought this was common. These findings could allow coaches and medical staff to align expectations regarding the likelihood of hip pain and hip pathologies in badminton players training at an elite level, by adjusting training regimens or implementing early screening.
