1. Body Fatness, Body Core Temperature, and Heat Loss During Moderate-Intensity Exercise.
- Author
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LIMBAUGH, JAYME D., WIMER, GREGORY S., LONG, LYNN H., and BAIRD, WILLIAM H.
- Subjects
HUMAN body composition ,OBESITY ,BODY temperature ,HEAT losses ,EXERCISE intensity ,TEMPERATURE effect - Abstract
Purpose: This study examined the influence of body fatness on body core temperature and heat loss responses during moderate-intensity exercise. Methods: Nine men with lower body fat and eight men with higher body fat, matched for aerobic fitness, completed 1 h of recumbent cycling at the same absolute intensity in a warm environment (30°C, 40% RH). Percent body fat was measured by hydrostatic weigh-ing, using oxygen dilution to determine residual volume. Esophageal temperature (?
es ), mean skin temperature (Tsk ), and local sweat rate (msw ) were measured at rest and continuously during exercise while forearm blood flow (FBF) was measured at rest and every 10 min during exercise. Results: The lower body fat and higher body fat groups were successfully matched for aerobic fitness, removing the influence of body fatness, given that Vo2peak was 50.72 ± 7.34 and 50.43 ± 5.01 ml · kg LBM-1 · min-1 , respectively. When compared to lower body fat individuals, % body fat, body surface area (AD ), and body mass were higher and AD / mass was lower in higher body fat individuals. Tes , Tsk , FBF, msw , and the slope of msw :Tes were not different between groups. Metabolic heat production was similar between the lower body fat (299.7 ± 40.5 W · m-2 ) and higher body fat (288.1 ± 30.6 W · m-2 ) subjects, respectively. Dry and evaporative heat loss, as well as heat storage during exercise, were not different between groups. Conclusion: These data suggest that there is no effect of body fatness on body core temperature or heat loss responses during moderate-intensity exercise in a warm environment. [ABSTRACT FROM AUTHOR]- Published
- 2013
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