Optimal cooling strategies for players in Australian Tennis Open conditions

Objectives

We compared the utility of four cooling interventions for reducing heat strain during simulated tennis match-play in an environment representative of the peak conditions possible at the Australian Open (45 °C, <10% RH, 475 W/m² solar radiation).

Design

Nine trained males undertook four trials in a climate chamber, each time completing 4 sets of simulated match-play.

Methods

During ITF-mandated breaks (90-s between odd-numbered games; 120-s between sets), either iced towels (ICE), an electric fan (FAN_dry), a fan with moisture applied to the skin (FAN_wet), or ad libitum 10 °C water ingestion only (CON) was administered. Rectal temperature (T_re), mean skin temperature (T_sk), heart rate (HR), thermal sensation (TS), perceived exertion (RPE) and whole body sweating (WBSR) were measured.

Results

After set 3, T_re was lower in ICE (38.2 ± 0.3 °C) compared to FAN_dry (38.7 ± 0.5 °C; p = 0.02) and CON (38.5 ± 0.5 °C; p = 0.05), while T_re in FAN_wet (38.2 ± 0.3 °C) was lower than FAN_dry (p = 0.05). End-exercise T_re was lower in ICE (38.1 ± 0.3 °C) and FAN_wet (38.2 ± 0.4 °C) than FAN_dry (38.9 ± 0.7 °C; p < 0.04) and CON (38.8 ± 0.5 °C; p < 0.04). T_sk for ICE (35.3 ± 0.8 °C) was lower than all conditions, and T_sk for FAN_wet (36.6 ± 1.1 °C) was lower than FAN_dry (38.1 ± 1.3 °C; p < 0.05). TS for ICE and FAN_wet were lower than CON and FAN_dry (p < 0.05). HR was suppressed in ICE and FAN_wet relative to CON and FAN_dry (p < 0.05). WBSR was greater in FAN_dry compared to FAN_wet (p < 0.01) and ICE (p < 0.001).

Conclusions

Fan use must be used with skin wetting to be effective in hot/dry conditions. This strategy and the currently recommended ICE intervention both reduced T_re by ～0.5–0.6 °C and T_sk by ～1.0–1.5 °C while mitigating rises in HR and TS.