Metabolic and thermal responses of women during cooling in water

Abstract

The metabolic and thermal responses of 10 young women, 3 lean (21–24% fat) and 7 obese (29–41% fat), were measured during head-out immersion in a stirred water bath maintained at 20°C. Continuous measurements of heat production (M), rectal (Tre, esophageal (Tes), and skin temperatures were obtained. The rate and magnitude of the increase in M and decrease in core temperatures were significantly greater in the lean than the obese group. Tissue insulation values for lean women were similar to those reported for diving and nondiving Korean women in 30°C water. Lean women with 22% body fat have a larger SA/mass ratio than men of comparable body fat content and cool at a greater rate. It is concluded that SA/mass as well as body fatness and size must be considered in the overall metabolic and thermal responses to cold exposure.