Total Energy Expenditure and Functional Status in Older Adults: A Doubly Labelled Water Study

Area of Science:

• Gerontology
• Human Physiology
• Nutritional Science

Background:

• Higher total energy expenditure (TEE) in free-living conditions is associated with reduced mortality in older adults.
• Good physical and functional test performance indicates a positive functional prognosis.
• The relationship between TEE and functional test performance in older adults remains unclear.

Purpose of the Study:

• To investigate the association between TEE, measured via doubly labeled water, and functional test performance in older adults.

Main Methods:

• Cross-sectional study involving 56 older adults.
• Functional status assessed using gait speed, 6-minute walk test, and handgrip strength.
• Total energy expenditure (TEE) measured using the doubly labeled water method; physical activity monitored via accelerometry.

Main Results:

• Higher TEE correlated with better performance in gait speed (r=0.266, p=0.047), 6-minute walk test (r=0.424, p=0.001), and handgrip strength (r=0.478, p=0.000).
• Multivariate analysis indicated TEE was associated with 6-minute walk test performance (ß=1.790, p=0.044) and fewer sedentary events (ß=6.389, p=0.038), adjusted for sex and fat-free mass.

Conclusions:

• Older adults with poorer functional status (lower gait speed, 6-minute walk test performance, and handgrip strength) may have lower TEE.
• Stimulating increased TEE is important for preventing health problems linked to low energy expenditure in older populations.