EFFECTS OF DIET AND EXERCISE ON ENERGY-EXPENDITURE IN POSTMENOPAUSAL WOMEN

The purpose of this study was to determine the effect of a 24-wk diet + exercise (DE) or diet-only program on basal metabolic rate (BMR), bo ne mineral density (BMD), energy expended during daily activities, mus cle strength, and maximal oxygen consumption (VO(2)max) in 40 postmeno pausal women. Daily energy need was determined by measuring BMR and as sessing physical activity with 8-d self-reported activity records. The DE group consumed 2092 kJ/d less than the daily energy need and walke d and performed strength-training exercises during which they expended an additional 837 kJ/d. The two diet-only groups consumed either 2092 kJ/d (D-2092) or 2929 kJ/d (D-2929) less than the daily energy need. BMD, BMR, muscle strength, VO(2)max, and energy expended during lying, sitting, standing, and walking were measured at baseline and after 12 and 24 wk of treatment. A significant decrease in BMR and energy expe nded during sitting and walking occurred in all groups, with no signif icant differences observed among groups. Although the declines in BMR were significant, they were small and may not have been physiologicall y relevant. No changes in BMD or VO(2)max occurred, whereas strength i ncreased significantly in the DE group. The results showed that postme nopausal women significantly improved their body composition over a pe riod of 6 mo without experiencing a large decline in BMR, BMD, or sele ct components of energy expenditure.