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 weighing, using oxygen dilution to determine residual volume. Esophageal temperature (T es ), mean skin temperature (T̄sk) , and local sweat rate ( ṁsw) 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 V̇ O2peak 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 A D/mass was lower in higher body fat individuals. T es , T̄sk , FBF, ṁsw , and the slope of ṁsw :T es 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.
Original language | English |
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Pages (from-to) | 1153-1158 |
Number of pages | 6 |
Journal | Aviation Space and Environmental Medicine |
Volume | 84 |
Issue number | 11 |
DOIs | |
State | Published - Nov 2013 |
Scopus Subject Areas
- Public Health, Environmental and Occupational Health
Keywords
- Adiposity
- Exertion
- Heat stress
- Thermoregulation.