Heat Stress Impacts on Elite Tennis Performance: Evidence from the Australian Open

Increasing temperatures create more challenges for outdoor elite sports, particularly high-intensity tournaments such as the Australian Open, where players frequently experience high thermal stress. This study investigates the impact of environmental heat stress on professional tennis performance using high-resolution data from professional tennis matches with environmental performance diagnostics. To quantify these impacts, ATP and WTA singles matches played at various Australian Open tournaments have been analysed in conjunction with ERA5-Land reanalysis data averaged per hour, covering air temperature, relative humidity, global radiation, and wind speed. Heat stress was computed using the Wet Bulb Globe Temperature index and categorised into heat danger levels according to the heat danger classification of Sports Medicine Australia. A hypothesis-driven, uncertainty-aware statistical framework was employed, utilising robust non-parametric tests, trend analyses, and Spearman rank correlations to evaluate the sensitivity of key performance metrics to escalating levels of heat stress. Overall, the results indicate that severe heat stress conditions negatively affect the efficiency of serve and return, the number of unforced errors, the level of performance variability, and the length of a match in ATP and WTA events. More specifically, aggressive serve-related variables, such as aces, demonstrate a partial level of resilience in severe heat, while rally complexity, shot variety, and return length decrease with increased levels of heat stress. When analysed by set status, the results further suggest that while one of the most elite players controls their playstyle in severe heat conditions, the lower-seeded players take more risks and tend to make errors. Taken together, these findings provide large-scale empirical evidence of the impacts of environmental stress during the Australian Open tournament games. In light of these findings, the Australian Open tournament should adjust its schedule to prioritise tennis players’ health, and future tournaments should be scheduled more precisely according to reports from climate scientists and data-informed schedules.