Accelerometer-derived moderate-to-vigorous-intensity physical activity: sex differences in health benefits and health equivalence between the sexes: a prospective cohort study

Background Current physical activity guidelines are sex-neutral despite well-recognized physiological sex differences. Previous studies have reported sex differences in associations between moderate-to-vigorous-intensity physical activity (MVPA) and several health outcomes. However, sex differences in these associations and the health equivalence of MVPA between the sexes remain incompletely understood across a broad range of outcomes. Sex differences in associations between moderate-to-vigorous-intensity physical activity (MVPA) and numerous health outcomes, and the health equivalence of MVPA between the sexes, remain unexplored. We aimed to identify sex differences in associations of MVPA with mortality and incident diseases, and to quantify the health equivalence of MVPA between the sexes. Methods Sex-specific associations of MVPA with all-cause, cardiovascular disease (CVD), and cancer mortality, and with incident diseases were examined using Cox and Fine-Gray models. Sex differences were tested using likelihood ratio tests comparing models with and without sex-by-MVPA interaction terms. The health equivalence of MVPA between the sexes was quantified for the selected outcomes. Results Among 86,196 individuals (43.1% male), 5,195 deaths occurred over a median 7.93-year follow-up. For mortality, sex differences were identified in the associations of MVPA with all-cause, CVD, and cancer mortality, with median male-to-female MVPA duration ratios of 0.90, 1.37, and 0.71, respectively. For disease incidence, no sex differences remained significant after correction for multiple testing. Among incident diseases with nominally significant sex differences, MVPA was significantly associated with 12 in women only and 4 in both sexes. Exploratory health equivalence analyses yielded median male-to-female MVPA duration ratios of 2.02, 2.59, 1.87, and 1.73 for coronary atherosclerosis, other unspecified chronic ischemic heart disease, chronic airway obstruction, and gastroesophageal reflux disease, respectively. Conclusion For mortality, significant sex differences were identified in the associations of MVPA with all-cause, CVD, and cancer mortality. For disease incidence, no significant sex differences were identified after correction for multiple testing. The health-equivalence estimates, based on model-predicted weekly MVPA durations, should be interpreted cautiously as exploratory findings and require independent validation.