Home Current Issue Previous Issues Published Ahead-of-Print Collections For Authors Journal Info
Skip Navigation LinksHome > November 2008 - Volume 40 - Issue 11 > To Cool, But Not Too Cool: That Is the Question-Immersion Co...
Medicine & Science in Sports & Exercise:
doi: 10.1249/MSS.0b013e31817eee9d
BASIC SCIENCES: Original Investigations

To Cool, But Not Too Cool: That Is the Question-Immersion Cooling for Hyperthermia

TAYLOR, NIGEL A. S.1; CALDWELL, JOANNE N.1; VAN DEN HEUVEL, ANNE M. J.1; PATTERSON, MARK J.2

Collapse Box

Abstract

Introduction: Patient coolingtime can impact upon the prognosis of heat illness. Although ice-cold-water immersion will rapidly extract heat, access to ice or cold water may be limited in hot climates. Indeed, some have concerns regarding the sudden cold-water immersion of hyperthermic individuals, whereas others believe that cutaneous vasoconstriction may reduce convective heat transfer from the core. It was hypothesized that warmer immersion temperatures, which induce less powerful vasoconstriction, may still facilitate rapid cooling in hyperthermic individuals.

Methods: Eight males participated in three trials and were heated to an esophageal temperature of 39.5°C by exercising in the heat (36°C, 50% relative humidity) while wearing a water-perfusion garment (40°C). Subjects were cooled using each of the following methods: air (20-22°C), cold-water immersion (14°C), and temperate-water immersion (26°C).

Results: The time to reach an esophageal temperature of 37.5°C averaged 22.81 min (air), 2.16 min (cold), and 2.91 min (temperate). Whereas each of the between-trial comparisons was statistically significant (P < 0.05), cooling in temperate water took only marginally longer than that in cold water, and one cannot imagine that the 45-s cooling time difference would have any meaningful physiological or clinical implications.

Conclusion: It is assumed that this rapid heat loss was due to a less powerful peripheral vasoconstrictor response, with central heat being more rapidly transported to the skin surface for dissipation. Although the core-to-water thermal gradient was much smaller with temperate-water cooling, greater skin and deeper tissue blood flows would support a superior convective heat delivery. Thus, a sustained physiological mechanism (blood flow) appears to have countered a less powerful thermal gradient, resulting in clinically insignificant differences in heat extraction between the cold and temperate cooling trials.

©2008The American College of Sports Medicine

Login

Article Tools

Share

Search for Similar Articles
You may search for similar articles that contain these same keywords or you may modify the keyword list to augment your search.

Connect With Us