Neuromuscular fatigue is characterised not only by a reduction in the capacity to generate maximal muscle force, but also in the ability to control submaximal muscle forces, i.e., to generate task-relevant and precise levels of force. This decreased ability to control force is quantified according to a greater magnitude and lower complexity (temporal structure) of force fluctuations, which are indicative of decreased force steadiness and adaptability, respectively. The “loss of force control” is affected by the type of muscle contraction used in the fatiguing exercise, potentially differing between typical laboratory tests of fatigue (e.g., isometric contractions) and the contractions typical of everyday and sporting movements (e.g., dynamic concentric and eccentric contractions), and can be attenuated through the use of ergogenic aids. The loss of force control appears to relate to a fatigue-induced increase in common synaptic input to muscle, though the extent to which various mechanisms (afferent feedback, neuromodulatory pathways, cortical/reticulospinal pathways) contribute to this remains to be determined. Importantly, this fatigue-induced loss of force control could have important implications for task performance, as force control is correlated with performance in a range of tasks that are associated with activities of daily living, occupational duties, and sporting performance.

Objectives To describe the incidence rate, severity, burden and aetiology of medical attention and time-loss injuries across five consecutive seasons at a professional ballet company. Methods Medical attention injuries, time-loss injuries and dance exposure hours of 123 professional ballet dancers (women: n=66, age: 28.0±8.3 years; men: n=57, age: 27.9±8.5 years) were prospectively recorded between the 2015/2016 and 2019/2020 seasons. Results The incidence rate (per 1000 hours) of medical attention injury was 3.9 (95% CI 3.3 to 4.4) for women and 3.1 (95% CI 2.6 to 3.5) for men. The incidence rate (per 1000 hours) of time-loss injury was 1.2 (95% CI 1.0 to 1.5) for women and 1.1 (95% CI 0.9 to 1.3) for men. First Soloists and Principals experienced between 2.0–2.2 additional medical attention injuries per 1000 hours and 0.9–1.1 additional time-loss injuries per 1000 hours compared with Apprentices (p≤0.025). Further, intraseason differences were observed in medical attention, but not time-loss, injury incidence rates with the highest incidence rates in early (August and September) and late (June) season months. Thirty-five per cent of time-loss injuries resulted in over 28 days of modified dance training. A greater percentage of time-loss injuries were classified as overuse (women: 50%; men: 51%) compared with traumatic (women: 40%; men: 41%). Conclusion This is the first study to report the incidence rate of medical attention and time-loss injuries in professional ballet dancers. Incidence rates differed across company ranks and months, which may inform targeted injury prevention strategies.

The aim of this study was to investigate the physical determinants of weightlifting competition performance based on Isometric Mid-Thigh Pull (IMTP) and Countermovement Jump (CMJ) force-time variables, in a cross-sectional and longitudinal analysis. Ten British advanced international female weightlifters’ competition results and neuromuscular assessment data collected as part of the British Weight Lifting World Class Programme were utilised for the purpose of this study. All data were averaged for two consecutive 1-year periods. The cross-sectional analysis utilised the second year of data, whereas the longitudinal analysis assessed the mean change between the two years. The cross-sectional analysis results reveal IMTP Net Isometric Peak Force (PF) and CMJ Peak Power (PP) predict 94.2%, 95.1% and 91.8% of the variance in Total, Snatch and Clean & Jerk competition performance, respectively (p = <0.5). The longitudinal analysis results revealed that ∆IMTP PF was the only predicting factor of longitudinal change in weightlifting competition performance predicting 41.5%, 41.7% and 42.5% of ∆Total, ∆Snatch and ∆Clean & Jerk, respectively (p = <0.5). The assessments and equations may be utilised by coaches or sports scientists to inform the prescription of training and help predict competition performance.

This study investigated whether anthropometric and physical abilities explained variance in match collision performance among international female rugby union players. Physical performance and anthropometric data for fifty‐one international female rugby union players, and collision actions categorised as “effort” or “performance” variables, from 20 international matches, were analysed using partial least squares regression. Among forwards, variance in carries/min was explained (R²= .22) by a combination of; body mass, skinfolds, acceleration momentum and negative associations with mean aerobic speed and single‐leg isometric squat relative force (SLISO/kgBM). Variance in collision dominance among forwards was explained (R² = .21) by lower skinfolds and higher acceleration momentum, while tackles/min (R² = .19) were explained by greater jumping power and single‐leg isometric squat (SLISO). Among backs, variance in tackles/min (R² = .54) was explained by greater bench press, SLISO and SLISO/kgBM. Variance in collision dominance among backs was explained (R² = .23) by negative and positive associations with body mass and SLISO/kgBM, respectively. These findings suggest the development of physical characteristics, such as body mass and composition, strength and power contribute towards successful collision actions among international female rugby union players. The contribution of different physical characteristics towards collision events is dependent on position, and whether the collision event is categorised by “performance” or “effort”. It is suggested that physical training programmes should reflect this level of specificity.

The nurturing of young players in youth academies is seen as an important step on the way to becoming a full professional in the sport of soccer. This longitudinal multi-study investigation, spanning 2009 to 2021, analysed the career paths of Spanish academy soccer players. It consisted of three studies investigating players’ transition from academy to professional status and the identification of technical skills and psychological traits which could distinguish future professionals from amateurs. The sample involved 198 male academy soccer players (aged 13.5–17.9) from two Madrid-based professional clubs. Study 1 assessed the outcomes of these players a decade after their academy-level evaluations. Studies 2 and 3 focused on the subgroup of 85 players whose playing status could be verified a decade later. Results showed that 12 players (6.1%) progressed to full-time professional soccer. Of these 12, just 7 reached Spain's highest professional league within 10 years of their final academy tests. Significant differences favouring professional players were observed in the trait of ‘self-confidence’, ‘ball reception’, ‘dribbling forward with the ball’ and coaches’ global technical assessments. In conclusion, the chances of academy soccer players achieving professional status are low. Accordingly, providing more developmental opportunities before deselection is crucial to maximise player potential. Coaches could prioritise players’ self-confidence and ball control to increase the conversion rate of academy players to professional status. Furthermore, recruitment of players who are already strong in these attributes could also improve the productivity of talent development pipelines.