DOI: 10.1093/aje/kwh299 Physical Activity and Changes in Weight and Waist Circumference in Midlife Women: Findings from the Study of Women’s Health Across the Nation

Controversy exists regarding the extent to which age, menopausal status, and/or lifestyle behaviors account for the increased weight, fat mass, and central adiposity experienced by midlife women. To address this question, the authors longitudinally examined the relations of aging, menopausal status, and physical activity to weight and waist circumference in 3,064 racially/ethnically diverse women aged 42–52 years at baseline who were participating in the Study of Women’s Health Across the Nation (SWAN), an observational study of the menopausal transition. Over 3 years of follow-up (1996–1997 to 1999–2000), mean weight increased by 2.1 kg (standard deviation (SD), 4.8) or 3.0 % (SD, 6.5) and mean waist circumference increased by 2.2 cm (SD, 5.4) or 2.8 % (SD, 6.3). Change in menopausal status was not associated with weight gain or significantly associated with increases in waist circumference. A one-unit increase in reported level of sports/exercise (on a scale of 1– 5) was longitudinally related to decreases of 0.32 kg in weight (p < 0.0001) and 0.10 cm in waist circumferenc