The relationship of deep and surface skin temperatures to the ventilatory responses elicited during cold water immersion.

Subjects were immersed for 10 min in water at 14.5 degrees C, after exposure either to ambient temperature or sauna heating. During the immersions, total ventilation, end-tidal PCO2, the mean of three surface skin temperatures, and deep skin temperatures were measured. There was a statistically significant correlation between the rate of change of deep skin temperature and the initial ventilatory responses evoked during both cold water immersions. After the sauna heating and cold water exposure, the temperature gradient through the skin appeared to be related to the ventilatory response. There was no significant correlation between the rate of change of mean surface skin temperature and the ventilatory response. The results suggest that the primary drive to increased ventilation during cold water immersion is the rate of change of deep skin temperature.