Trends in Meeting the Physical Activity Guidelines: Muscle-Strengthening Alone and Combined With Aerobic Activity, United States, 1998-2018

Background: The National Health Interview Survey is unique among US federal surveillance systems with over 20 years of consistent assessment of muscle-strengthening and aerobic activity. The authors examined trends in the prevalence of US adults who met the muscle-strengthening (2 or more days per week) and the combined muscle-strengthening and aerobic physical activity (at least 150 min/wk of moderate-intensity equivalent activity) guidelines from 1998 to 2018. Methods: The 1998–2018 National Health Interview Survey data were analyzed. Age-adjusted prevalence of meeting the muscle-strengthening and combined aerobic and muscle-strengthening guidelines by selected respondent characteristics were estimated for each year and linear and higher-order trends were assessed. Results: From 1998 to 2018, prevalence of meeting the muscle-strengthening guideline increased from 17.7% to 27.6%, and meeting the combined aerobic and muscle-strengthening guidelines increased from 14.4% to 24.0%. All subgroups demonstrated significant increases in meeting both guideline measures over this period although trends varied across the 21 years; increasing trends were more commonly sustained in the second decade of monitoring. Conclusions: Although increasing trends in prevalence of meeting the muscle-strengthening and combined guidelines are encouraging, current prevalence estimates remain low. Opportunities exist for the continued promotion of muscle-strengthening activity using evidence-based approaches.