Comparison of exercise in air and in water of different temperatures*

Abstract

Exercise in air and in water was studied using an ergometer which required the same type of muscle action in both environments. The V̇o2 for a given load was the same in air and in water of 30°C and 35°C and was linearly related to the rate of work. In 25°C water V̇o2 was .14 l/min greater than under the other conditions. In water respiratory frequency was slightly greater than in air but relationships between V̇E and V̇o2 were not different. Temperature measurements during 30 minutes of work at 80 watts in one lean individual revealed that the increase of temperature in the external auditory canal (Tear) was directly related to the water temperature, but in an obese subject there was no such relationship. However, weight loss during the exercise was related to water temperature in both subjects. Heart rate of the lean subject was slower in cool water than in air or warm water, but for the obese subject pulse rate did not correlate with the water temperature. Except for differences related to thermal regulation and the mechanics of respiration, responses to exercise are the same in water as those in air.