Keim N L, Belko A Z, Barbieri T F
USDA, ARS, Western Human Nutrition Research Center, Presidio of San Francisco, CA 94129, USA.
Int J Sport Nutr. 1996 Dec;6(4):356-69. doi: 10.1123/ijsn.6.4.356.
Energy expenditure (EE) was measured at specific steady-state work rates to determine if body fat percentage or gender was associated with exercise EE, substrate oxidation, or work efficiency. Body fat percentage (leaner vs. fatter men, 9-15% vs. 20-25% fat; leaner vs. fatter women, 16-24% vs. 32-48% fat) was not related to work efficiency or submaximal EE. Fatness affected substrate oxidation in men but not in women. Compared to fatter men, leaner men had higher fat oxidation (6.7 +/- 1.6 vs. 1.4 +/- 2.0 mg.kg fat-free mass [FFM]-1.min-1; p < .01) and lower carbohydrate oxidation (26.6 +/- 4.2 vs. 39.3 +/- 5.0 mg.kg FFM-1.min-1; p < .01) at 60% VO2max. When men and women of similar fatness and relative aerobic capacity were compared, men had higher EE measured as kilojoules per minute but similar rates of EE and substrate oxidation per kilogram of FFM at 40-60% VO2max. It was concluded that body FFM, not fatness, is a determinant of exercise EE, whereas fatness is associated with differences in exercise substrate oxidation in men. Along with aerobic fitness, gender and fatness should be considered in future studies of exercise substrate oxidation.
在特定的稳定工作强度下测量能量消耗（EE），以确定体脂百分比或性别是否与运动EE、底物氧化或工作效率相关。体脂百分比（较瘦与较胖男性，体脂率9 - 15% 与20 - 25%；较瘦与较胖女性，体脂率16 - 24% 与32 - 48%）与工作效率或次最大运动EE无关。肥胖影响男性的底物氧化，但不影响女性。与较胖男性相比，较瘦男性在60%最大摄氧量（VO2max）时脂肪氧化更高（6.7 ± 1.6 与1.4 ± 2.0毫克·千克去脂体重[FFM]-1·分钟-1；p < 0.01），碳水化合物氧化更低（26.6 ± 4.2与39.3 ± 5.0毫克·千克FFM-1·分钟-1；p < 0.01）。当比较体脂和相对有氧能力相似的男性和女性时，在40 - 60% VO2max时，男性以每分钟千焦衡量的EE更高，但每千克FFM的EE和底物氧化速率相似。得出的结论是，身体的FFM而非肥胖是运动EE的决定因素，而肥胖与男性运动底物氧化的差异有关。在未来关于运动底物氧化的研究中，除了有氧适能外，还应考虑性别和肥胖因素。
