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This case study aims to examine changes in the lower limb joint kinematic profile and performance stability induced by repeated ski runs in two world‐class alpine skiers. Two Olympic medallist alpine skiers were tested during their slalom training, with continuous recording of right knee and hip angles, along with turn time and run time. The eight runs of the training session were analysed with linear mixed models. Results showed no effect of runs repetition on performance (i.e., run and turn time; P ≥ 0.279). There was no global effect of runs repetition on minimal and maximal angles for either the knee or the hip (P > 0.151). There was an interaction between run and leg for the maximal angle of both the knee and hip (P ≤ 0.047), which increased across runs for the outside leg and decreased for the inside leg. The maximal angular velocity for both the knee and hip increased with runs repetition in extension (P ≤ 0.028). There were no overall changes in maximal angular velocity in flexion with runs repetition (P ≥ 0.264), but there was an interaction between run and leg for the knee (P < 0.001) due to faster eccentric velocities across runs for the outside leg and slower velocities for the inside leg. In conclusion, the observed joint kinematic alterations without concomitant performance impairment support the concept of multiple movement strategies in athletes to achieve similar performance, especially under fatigue conditions. [ABSTRACT FROM AUTHOR]

This study characterised the thigh muscle-tendon unit length variations (MTUv) in elite alpine skiing. MTUv were modelled for seven muscles from knee and hip angles in 17 national team skiers during 1602 cycles (546 Slalom (SL), 908 Giant-Slalom (GS), 136 Super-Giant (SG) and 12 Downhill (DH) cycles). The biarticular rectus femoris showed a dynamic pattern on both legs, especially in SL. On the other side, vastii displayed a stable length on the inside leg in all disciplines (37–46% of the cycle), contrasting with their dynamic behaviour on the outside leg being quasi-static for only 3% (SL) to 27% (DH) of the cycle. SL showed the largest amplitude of MTUv followed by GS, SG and DH. For vastus lateralis, MTUv was ~60%Lr.s−1 in SL but only ~12%Lr.s−1 in DH. In SL, a fine desynchronisation between both joints led to nearly constant MTUv (slow lengthening lasting ~45-51% of the cycle) for the biarticular hamstrings separated by faster variations during turn switch from outside to inside leg. In summary, biarticular MTUv were not characterised by single-joint behaviours, suggesting that extrapolating contraction regimen from knee joint only is not accurate in alpine skiing. [ABSTRACT FROM AUTHOR]

Purpose: To determine the effect of cold ambient conditions on proprioception and cognitive function in elite alpine skiers. Methods: 22 high-level alpine skiers and 14 control participants performed a proprioceptive-acuity (active movement-extent discrimination) and a cognitive (planning task) test in cold (8°C) and temperate (24°C) ambient conditions. Results: All participants displayed an increase in thermal discomfort and the amount of negative affects in the cold environment (all P < .05). Average proprioceptive acuity was significantly better in the elite skiers (0.46° ± 0.12°) than in the control group (0.55° ± 0.12°) (P < .05) and was not affected by cold ambient conditions, except for a shift in the pattern of error (over- vs underestimation, P < .05). Cognitive performance was similar between elite skiers and control participants in temperate environments but decreased in the cold in the control group only (P < .05) becoming lower than in elite skiers (P < .05). Conclusion: Elite alpine skiers showed a significantly better proprioceptive acuity than a control population and were able to maintain their performance during a cognitive task in a cold environment. [ABSTRACT FROM AUTHOR]

Objectives: To analyse 11 years of FIVB heat stress-monitoring data to determine the relative influence of the different environmental parameters in increasing the likelihood of a heat-related medical time-out (MTOheat).Methods: A total of 8530 matches were recorded. The referee measured air temperature, black globe temperature, relative humidity and wet-bulb globe temperature (WBGT) before the matches, and registered the MTOheat. The absolute humidity was computed at posteriori.Results: There were 20 MTOheat cases, but only 3 resulted in forfeiting the match. MTOheat incidence was not statistically impacted by sex (p=0.59). MTOheat cases were more prevalent during the games played in Asia during the 4th quarter of the year (p<0.001). Two cases of MTOheat experienced diarrhoea or gastroenteritis during the 5 preceding days; both of them forfeited the match. A principal component analysis showed a specific environmental profile for the matches with MTOheat. They occurred at higher WBGT, temperatures and absolute humidity (p<0.001), but with a lower relative humidity (p=0.027).Conclusions: The current data showed that an increase in ambient or black globe temperature, but not relative humidity, increased the risk of a MTOheat; but that the absolute risk remained low in elite beach volleyball players. However, suffering or recovering from a recent illness may represent a risk factor for a MTOheat to lead to player forfeit. [ABSTRACT FROM AUTHOR]

This study aimed to characterise the thermoregulatory responses of elite alpine skiers. Core (gastro-intestinal) and skin temperatures were recorded continuously from 4 national team skiers representing 18 training-sessions for a total of 83 ski runs (average ambient temperature 1.9°C). Shivering responses were estimated from quadriceps and hamstrings EMG recordings during 77 chairlifts. Temperature responses were also obtained from 6 accompanying staffs representing 16 training-sessions (passive in 10 cases, following the skiers in 6 cases). Core temperature of the skiers (P < .001) but not the staff (P = .103) increased during training and was higher in skiers than staff after one-third of the training session (P < .006). Conversely, average skin temperature of the skiers decreased during training (P < .001) and was lower in skiers than staff for the second half of the training. Muscle activity during chairlifts remained below 1% and there was no meaningful shivering. Muscle activity decreased whilst mean and median power frequency increased during the chairlift (P < .020). Muscle activity was also lower during the last lift than the first one whilst mean and median power frequency were higher (P < .020). In conclusion, skin temperature decreased during Slalom and Giant Slalom in elite alpine skiers, likely due to the limited insulative capacity of the racing suit and the high velocity increasing convective heat loss. Conversely, core temperature increased during the training session suggesting that the metabolic heat production was larger than the convective heat loss, and was also sufficient to maintain homeostasis without shivering. [ABSTRACT FROM AUTHOR]

The International Olympic Committee's (IOC) consensus statement on 'methods for recording and reporting of epidemiological data on injury and illness in sport' recommended standardising methods to advance data collection and reporting consistency. However, additional aspects need to be considered when these methods are applied to specific sports settings. Therefore, we have developed a snow sports-specific extension of the IOC statement to promote the harmonisation of injury and illness registration methods among athletes of all levels and categories in the different disciplines governed by the International Ski and Snowboard Federation (FIS), which is also applicable to other related snow sports such as biathlon, ski mountaineering, and to some extent, para snow sports. The panel was selected with the aim of representing as many different areas of expertise/backgrounds, perspectives and diversity as possible, and all members were assigned to thematic subgroups based on their profiles. After panel formation, all members were provided with an initial draft of this extension, which was used as a basis for discussion of aspects specific to the discipline, application context, level and sex within their snow sports subgroup topic. The outcomes were then aligned with the IOC's existing consensus recommendations and incorporated into a preliminary manuscript draft. The final version of this snow sports-specific extension was developed and approved in two iterative rounds of manuscript revisions by all consensus panel members and a final meeting to clarify open discussion points. This snow sports-specific extension of the IOC statement is intended to guide researchers, international and national sports governing bodies, and other entities recording and reporting epidemiological data in snow sports to help standardise data from different sources for comparison and future research., Competing Interests: Competing interests: MM is a deputy editor, LE is an IPHP editor and BC and EV are associate editors at BJSM., (© Author(s) (or their employer(s)) 2025. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ Group.)