News - Chilly Things
Evaporative Cooling REALLY Works!
In July 2010 the the NRC Research Press, a division of Canadian Science Publishing in Applied Physiology, Nutrition, and Metabolism did a study on body cooling methods. Guess what came out on top of the list! Most methods were considered impractical or useless, all but the water-perfused vest - i.e. (a smaller version, the Chilly Tube!)
The human thermoregulatory system normally maintains body temperature within safe limits during heat exposure or while exercising. However, many professional, occupational, and recreational activities (e.g., firefighters, military personnel, astronauts, athletes) require physical work in hot and (or) humid environments, and some individuals perform these activities while wearing garments that impair evaporative cooling. In this condition the thermoregulatory system may be unable to dissipate sufficient heat, resulting in rapid heat storage, decreased work capacity, and, in extreme cases, heat illness and death.
Regional and whole-body cooling methods reduce heat strain and improve work tolerance in subjects exposed to hot environments. Such cooling methods include using air or water-cooled vests, ice packs, and cooling suits. However, most of these methods require heavy equipment, batteries, or power, and may be impractical for use in a field environment.
The purpose of this study was to evaluate the effectiveness of the rapid thermal exchange device cooling system to slow the development of hyperthermia and associated symptoms in subjects while walking in a hot environment and wearing military clothing. Contrary to our hypothesis and previous studies, we found no attenuation of the rise in core temperature or other improvement in physiological responses when subjects used the rapid thermal exchange device compared with the no cooling control condition. Immersing a hand in cold water also failed to provide a significant benefit over the no cooling condition. Only the water cooling vest was effective in reducing heat strain and extending exercise duration.
For the full article, please go to: