Moderate to high levels of exercise are associated with higher resting energy expenditure in community-dwelling postmenopausal women

Postmenopausal women experience an age-related decline in resting energy expenditure (REE), which is a risk factor for energy imbalance and metabolic disease. Exercise, by association with greater lean tissue mass and other factors, has the potential to mediate REE decline, but the relationship between exercise and REE in postmenopausal women is not well characterized. This study tests the hypothesis that exercise energy expenditure (EEE) is positively associated with REE, opposing the effects of age and menopause. The study tests this hypothesis in a cross-sectional sample of healthy postmenopausal women (N = 31, aged 49 - 72 years) with habitual exercise volumes at or above levels consistent with current clinical recommendations. Subjects kept four weeks of exercise diaries quantifying exercise activity, and were measured for body composition, maximal oxygen uptake, and REE. Multiple regression analysis was used to test for relationships between EEE, age, body composition, and REE. EEE and lean tissue mass (fat-free mass: FFM; and fat-free mass index: FFMI) exhibited significant, positive relationships with REE. The relationship between REE and EEE remained significant even after controlling for lean tissue mass. These results support the hypothesis that exercise is positively associated with REE, counter to the negative effects of age and menopause, and indicate a continuous relationship between exercise and REE across the moderate-to-high exercise range. Exercise at levels at and above current clinical guidelines may, in part, ameliorate risk for energy imbalance and metabolic disease through a positive relationship with REE