Effect of Half Time Cooling on Thermoregulatory Responses and Soccer-Specific Performance Tests

This study examined two active coolings (forearm and hand cooling, and neck cooling) during a simulated half-time recovery on thermoregulatory responses and subsequent soccer-specific exercise performance. Following a 45-min treadmill run in the heat, participants (N=7) undertook 15-min recovery with either passive cooling, forearm and hand cooling, or neck cooling in a simulated cooled locker room environment. After the recovery, participants performed a 6×15-m sprint test and Yo-Yo Intermittent Recovery Level 1 test (YYIR1) in a temperate environment. During the 15-min recovery, rectal temperature fell significantly (p 0.05). Neither active coolings induced further reduction in rectal temperature compared to passive cooling. No effect of active coolings was found in repeated sprint test. However, neck cooling reduced (p 0.05) the thermal sensation (TS) compared to passive cooling during the 15-min recovery. Active coolings attenuated (p 0.05) the sweat rate compared to passive cooling: 1.2±0.3 l•h-1 vs. 0.8±0.1 l•h-1 vs. 0.8±0.3 l•h-1, for passive cooling, forearm and hand cooling, and neck cooling, respectively. For passive cooling, elevated sweat rate resulted in higher (p 0.05) dehydration (2.1±0.3%) compared to neck cooling (1.5±0.3%) and forearm and hand cooling (1.4±0.3%). YYIR1 was improved (p 0.05) following forearm and hand cooling (869±320 m) and neck cooling (814±328 m) compared to passive cooling (654±311 m). Neck cooling (4.6±0.6) reduced (p=0.03) the session TS compared to passive cooling (5.3±0.5). These results suggest that active coolings effectively improved comfort and sweating response, which delayed exercise-heat induced performance diminish during a second bout of exercise.