Association between physical activity and bone mineral density in postmenopausal women: a cross-sectional study from the NHANES 2007–2018

BACKGROUND: Physical activity (PA) is generally encouraged for the treatment of osteoporosis. However, epidemiological statistics on the level of physical activity required for bone health are scarce. The purpose of this research was to analyze the association between PA and total spine bone mineral density (BMD) in postmenopausal women. METHODS: The research study included postmenopausal women aged ≥ 50 from the National Health and Nutrition Examination Survey. The metabolic equivalent (MET), weekly frequency, and duration of each activity were used to calculate PA. Furthermore, the correlations between BMD and PA were investigated by multivariable weighted logistic regression. RESULTS: Eventually, 1681 postmenopausal women were included, with a weighted mean age of 62.27 ± 8.18 years. This study found that performing ≥ 38MET-h/wk was linked to a lower risk of osteoporosis after controlling for several covariates. Furthermore, the subgroup analysis revealed that the connection between total spine BMD and moderate-to-vigorous PA was more obvious among postmenopausal women aged < 65 years or individuals with normal BMI (< 25 kg/m(2)). CONCLUSION: Physical activity ranging from moderate to vigorous was linked to higher total spine BMD in postmenopausal women. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13018-023-03976-2.