The adipokinetic effect of hyperthermic stress in man

The purpose of this investigation was to assess the alteration in serum free fatty acid concentrations during heat stress and dehydration. Each subject was exposed to heat stress in an environment chamber on 2 separate occasions. During the first exposure the subjects remained seated until the core temperature was elevated 1.4degreesC resulting in a mean weight loss of 1.66 kg due to dehydration. The second condition involved water replacement equal to the weight loss of the initial dehydration condition. Blood samples were obtained prior to heat exposure, when the core temperature was elevated 0.7degreesC and 1.4degreesC. They were subsequently analyzed for free fatty acids (FFA), glucose and lactin acid. Heart rates and core temperatures were monitored at 4 min intervals. During the dehydration condition the mean change in serum FFA was 0.9 muEq/ml in contrast to 0.2 muEq/ml for the rehydration condition. Serum levels of glucose increased moderately throughout the exposure (8 mg-%).