thermoregulation, heat illness, cooling, environmental physiology


Context: Athletes running in a hot, humid environment may have an increased risk of heat illness. In the 2004 Olympic Games, American and Australian athletes were provided with ice vests designed to cool their bodies before performance. The vest appeared to be effective in keeping body temperatures down and improving the performance of the marathoners. However, body temperatures have not been reported when the vest was used before an actual competition. Objective: To determine if wearing the Nike Ice-Vest decreased core temperature (Tc) before and during athletic performance in warm (26°C to 27°C), humid (relative humidity = 50% to 75%) conditions. Results: Ten minutes before the start of the race, Tc was elevated by 0.84°C ± 0.37°C in the no-vest group, compared with 0.29°C ± 0.56°C in the ice-vest group (P < .01). This difference in Tc persisted at 1 minute before the start. Immediately after the finish, the increase in Tc averaged 2.75°C ± 0.62°C in the no-vest group and 2.12°C ± 0.62°C in the ice-vest group (P < .01). Conclusions: Wearing an ice vest before cross-country performance in warm, humid conditions allowed athletes to start and finish the competition with a lower Tc than did those who did not wear a vest.

Original Publication Citation

Hunter I, Hopkins JT, & Casa D. (26). "Core Body Temperature Before and After Cross-Country Racing after Warming Up with an Ice Vest". Journal of Athletic Training, 41(4), 371-374.

Document Type

Peer-Reviewed Article

Publication Date


Permanent URL


National Athletic Trainer's Association




Life Sciences


Exercise Sciences