Association between exercise patterns and bone mineral density in postmenopausal African American women: The HASAAW study

According to the National Osteoporosis Foundation, 5% of African American women over 50 years of age have osteoporosis and an additional 35% have osteopenia, which puts them at risk for osteoporosis and fractures. Weight-bearing exercise has been shown to maintain bone mineral density (BMD) in white women, but little research has been reported in African American women. According to the CDC only 29% of African American women aged 45-64 are meeting their recommendations that adults engage in 30 minutes of exercise 3-5 days per week. The purpose of this study was to determine if reported weight-bearing exercise is associated with better BMD in community-dwelling African American women.

Data are from the Health Assessment Survey of African American Women (HASAAW), a cross sectional study conducted in Southern California from 1992-1999. There were, 337 postmenopausal African American women, mean age 62 years, mean BMI 29, of whom 5% had osteoporosis (BMD < -2.5). Most were sedentary white collar workers, but 22% percent were in an organized exercise program and 8% reported weight-training exercise. Hierarchal linear regression analysis indicated that being in an organized exercise program was significantly associated with increased total hip BMD, while weight lifting in the last 2 weeks was significantly associated with increased lumbar spine BMD (p < 0.05). Future research should be conducted on BMD and exercise in African American women, to determine the optimal types and amount of physical activity needed to maintain or increase BMD at the hip and spine.