Influence of Theobromine on Heat Production and Body Temperatures in Cold-Exposed Humans: A Preliminary Report.

摘要

One of the most successful class of drugs employed to enhance cold tolerance in animals appears to be the methylxanthines. Indeed, methylxanthines such as caffeine, theophylline and theobromine have been shown to increase heat production, delay hypothermia and thus improve cold tolerance in animals. In humans, theophylline and caffeine (taken in combination with ephedrine) have similarly been shown to improve cold tolerance. Whether theobromine could enhance tolerance to cold in humans, is not known. The influence of theobromine was thus investigated in eight healthy young male subjects during two semi-nude exposures to cold air (3h, 7C, 1 m/s wind speed). The ingestion of theobromine produced two different types of responses, as shown by a significant interaction between the effect of group and the effect of drug treatment on the rate of decrease in mean body temperatures. The present results are interpreted as indicating that the ingestion of theobromine in subjects capable of producing a relatively high metabolic response to the cold, significantly improves cold tolerance by increasing heat production, mainly from a greater lipid utilization. Keywords: Core temperature, Carbohydrate, Cold air, Energy substrates, Heat production, Heat losses, Hypothermia, Lipid, Metabolism, Oxygen consumption, Protein, Skin temperature. (kt)