Effects of Half-Time Cooling Using A Cooling Glove and Jacket on Manual Dexterity and Repeated-Sprint Performance in Heat.

This study aimed to assess the separate and combined effects of a cooling glove (CG) and a gel-cooling jacket (CJ) used during a half-time break on manual dexterity performance (Purdue Pegboard test) and subsequent repeat-sprint cycling performance in hot conditions. Twelve male athletes performed four experimental trials (within subjects, counterbalanced design) that consisted of: wearing a CG, wearing a CJ, combination of CG and CJ (CG+J) or a no-cooling control (NC) for 15 min during a 20 min half-time break performed between 2 x 30 min repeated-sprint cycling bouts in heat (35.0 ± 1.2°C and 52.5 ± 7.4% RH). Manual dexterity (dominant and non-dominant hand) was assessed immediately before and after the first-half of exercise, then immediately after cooling and the second-half of exercise. No differences were found for manual dexterity performance between trials or over time (p > 0.05). Additionally, no differences were found for power and work performance variables assessed during the second-half of exercise (p > 0.05), however participants felt 'cooler' wearing CG+J compared to NC (Thermal Sensation scale; p = 0.041). Further, no differences were found between trials for changes in gastrointestinal core temperature for any time period assessed (p > 0.05). In conclusion, the cooling trials did not affect manual dexterity or second-half repeated-sprint cycling performance compared to NC.