The relationship between physiological and performance variables during a hot/humid international rugby sevens tournament

ABSTRACT

To characterise physiological responses to competing in an international rugby sevens tournament played in hot/humid conditions, core temperature (T_c) and T_c predictors were collected from 11 elite men’s rugby sevens athletes competing in the Oceania sevens tournament in Suva, Fiji. T_c, body mass change, sweat electrolytes, playing minutes, total running distance, high speed running distance (HSD), psychrometric wet bulb temperature and exertional heat illness symptoms were collected pre, during and post games. Linear mixed-models were used to assess the effect of T_c predictors on post-game T_c, along with differences in T_c across measurement periods. Compared to baseline on both tournament days, mean T_c was higher during all between game (recovery) measures (all d >1.30, p <0.01). On both tournament days, eight athletes reached a post-game T_c >39.0°C, with several athletes reaching >39.0°C during warm-ups. Mean post-game T_c was related to playing minutes, total running distance, HSD, and post warm-up T_c (all p < 0.01). The T_c during warm-ups and games regularly exceeded those demonstrated to be detrimental to repeated sprint performance (> 39°C). Warm-up T_c represents the easiest predictor of post-game T_c to control via time/intensity modulation and the use of appropriate pre- and per-cooling strategies. Practitioners should be prepared to modulate warm-ups and other heat preparation strategies based on likely environmental conditions during hot/humid tournaments.

KEYWORDS:

• Sport
• body temperature
• athletes
• thermoregulation
• environment
• exertional heat illness

Acknowledgements

The authors would like to thank the athletes and coaches for agreeing to participate in this research during competition. We also acknowledge New Zealand Rugby for providing travel and accommodation during data collection and to High Performance Sport New Zealand for providing funding for consumables. Additionally, thanks to Damian Banks for his assistance with data collection.

Disclosure statement

No potential conflict of interest was reported by the author(s).