Purpose: This study aimed to examine physical activity (PA) as a protective measure of health outcomes among sexual minority (SM) and heterosexual adults. Methods: Using data from the 2018 National Health Interview Survey, differences in key health outcomes between three groups (heterosexual, SM, and "other") and the mediating effects of PA were explored. Chi-square tests were used to examine group differences. Multinomial logistic regression models were fit to examine associations between PA and health outcomes (body mass index [BMI], psychological distress, health status, and use of alcohol, cigarettes, and e-cigarettes). Results: Compared with heterosexual respondents, "other" adults had higher levels of BMI above 24.9 and were less active; SM respondents had elevated levels of alcohol use, smoking, binge drinking, and psychological distress, and reported worse overall health status. Unadjusted models showed that PA served as a protective factor for BMI above 30 and health status for all groups. PA was also protective for BMI below or above 18.5-24.9, smoking, psychological distress, and health status for both heterosexual and SM groups. Alternatively, PA behaved as a risk factor for alcohol use and binge drinking for all groups. Adjusted modeling removed PA as a risk factor for light alcohol use and binge drinking for SM respondents and added a protective factor for e-cigarette use for heterosexual respondents. Conclusion: This study adds to current literature on health disparities affecting SM populations and the health benefits associated with PA. Further research is needed to explore tailored PA intervention for SM populations and those who mark "other," "something else," "don't know," or refuse to answer questions on sexual orientation.
Keywords: LGB; National Health Interview Survey; physical activity; sexual minority adults.