University of Florida, Department of Aging and Geriatric Research, Gainesville, FL 32611-0107, USA.
Am J Clin Nutr. 2009 Nov;90(5):1336-42. doi: 10.3945/ajcn.2009.27659. Epub 2009 Sep 9.
Change in body composition, specifically loss of fat-free mass and gain in fat mass, in older adults is a major pathway leading to the onset of functional decline and physical disability.
The objective was to determine the association of activity-related energy expenditure with change in body mass and composition among older men and women.
Total energy expenditure (TEE) was assessed over 2 wk by using the doubly labeled water method in 302 community-dwelling older adults aged 70-82 y. Resting metabolic rate (RMR) was measured by using indirect calorimetry, and the thermic effect of meals was estimated at 10% of TEE. Activity energy expenditure (AEE) was calculated as [TEE(0.9) - RMR]. Total body mass, fat-free mass (FFM), and fat mass (FM) were assessed by dual-energy X-ray absorptiometry annually over a mean (+/-SD) of 4.9 +/- 1.3 y.
In multivariate models adjusted for baseline age, smoking status, and race, men and women had a decline (in kg/y) in body mass (men: -0.34, 95% CI: -0.71, 0.02; women: -0.45, 95% CI: -0.71, -0.19) and FFM (men: -0.48, 95% CI: -0.67, -0.29; women: -0.14, 95% CI: -0.026, -0.03). No changes (in kg/y) were observed in FM (men: 0.14, 95% CI: -0.10, 0.38; women: -0.28, 95% CI: -0.49, -0.07). In men and women, higher AEE at baseline was associated with greater FFM. The average change in these outcomes (ie, slope), however, was similar across tertiles of AEE.
These data suggest that accumulated energy expenditure from all physical activities is associated with greater FFM, but the effect does not alter the trajectory of FFM change in late life.
老年人身体成分的变化，特别是无脂肪质量的损失和脂肪质量的增加，是导致功能下降和身体残疾的主要途径。
本研究旨在确定与老年人身体质量和成分变化相关的与活动相关的能量消耗。
通过双标记水法在 302 名年龄在 70-82 岁的社区居住的老年人中，每两周评估一次总能量消耗（TEE）。间接测热法测量静息代谢率（RMR），并估计 TEE 的 10%为膳食的热效应。活动能量消耗（AEE）计算为[TEE（0.9）-RMR]。每年通过双能 X 射线吸收法评估总体质量、无脂肪质量（FFM）和脂肪质量（FM），平均（+/-SD）为 4.9+/-1.3 年。
在调整基线年龄、吸烟状况和种族的多变量模型中，男性和女性的体重（男性：-0.34，95%CI：-0.71，0.02；女性：-0.45，95%CI：-0.71，-0.19）和 FFM（男性：-0.48，95%CI：-0.67，-0.29；女性：-0.14，95%CI：-0.026，-0.03）均下降。FM （男性：0.14，95%CI：-0.10，0.38；女性：-0.28，95%CI：-0.49，-0.07）无变化（kg/y）。在男性和女性中，基线时较高的 AEE 与更大的 FFM 相关。然而，这些结果的平均变化（即斜率）在 AEE 的三分位数中相似。
这些数据表明，所有体力活动的累积能量消耗与更大的 FFM 相关，但该影响不会改变老年人晚期 FFM 变化的轨迹。
