Effect of heat exposure on thermoregulation and hockey-specific response time in field hockey goalkeepers

This study examined the thermoregulatory responses in field hockey goalkeepers during games (Part A), and assessed the effect of heat stress on hockey-specific response time (Part B). In Part A, core temperature (T_c), skin temperature (T_sk), body mass, fluid consumption and heart rate (HR) responses of six goalkeepers during two premier level club games in the Western Australian (winter) hockey season were recorded. Part B assessed the same measures, plus a response time test on four goalkeepers playing a simulated game inside a climate chamber in cool (COOL: 20 °C, 40% RH) and hot (HOT: 35 °C, 40% RH) conditions. In Part A, the mean (±SD) T_c and T_sk measured in games was 38.49 ± 0.20 °C and 34.99 ± 0.99 °C, with increases from baseline of 1.34 ± 0.19 °C and 1.08 ± 0.30 °C, respectively. Most of the increase in T_c resulted from the pre-game warm-up. In Part B, T_c and T_sk only increased significantly (p < 0.05) from baseline in the HOT condition (0.62 ± 0.18 °C and 1.61 ± 0.82 °C, respectively). Response time was significantly slower (0.87 ± 0.14 s, p < 0.01) after heat exposure, compared to COOL (0.75 ± 0.15 s), but the number of correct responses was not affected. For optimal performance, careful attention should be given to strategies to limit T_c increases in field hockey goalkeepers during matches.