Feelings of energy are associated with physical activity and sleep quality, but not adiposity, in middle-aged postmenopausal women

Objective: Feelings of fatigue and low energy are widespread among middle-aged women and have been shown to negatively affect quality of life. The aim of the present study was to examine the associations among adiposity, physical activity, and feelings of fatigue and energy in postmenopausal women. Methods: Postmenopausal women (N = 74; mean [SD] age, 58.9 [3.8] y) were assessed for adiposity (via dual-energy x-ray absorptiometry), steps per day, minutes of moderate to vigorous physical activity per day (via an accelerometer), prior week intensity of psychological vigor (via the Profile of Mood States-Short Form), and prior month frequency of energy feelings (via the vitality scale of the 36-item Medical Outcomes Survey-Short Form). Sleep quality was measured using the Pittsburgh Sleep Quality Index, depression was measured using the Beck Depression Inventory-II, and perceived stress was measured using the Perceived Stress Scale. Results: Adiposity was negatively related to steps per day (r = -0.55, P < 0.05) and minutes of moderate to vigorous physical activity per day (r = -0.48, P < 0.05). Adiposity was not significantly related to vigor, vitality, or any other psychological measures. Greater vitality was associated with lower total number of medications (r = -0.31, P < 0.01), more steps per day (r = 0.28, P < 0.05), and higher minutes of moderate to vigorous physical activity per day (r = 0.37, P < 0.01). Prior week feelings of vigor were unrelated to any variable of interest. Regression analyses revealed that minutes of moderate to vigorous physical activity per day independently explained 8% of the variance in vitality, whereas sleep quality was also a significant predictor of vitality (both P < 0.05). Conclusions: Engaging in recommended amounts of moderate to vigorous physical activity per day is associated with higher monthly frequency of energy feelings, regardless of adiposity status, in middle-aged postmenopausal women.