Results from the National Health Interview Survey show that between 2008 and 2013, the percentage of people meeting the Department of Health and Human Services 2008 Physical Activity Guidelines for Americans increased for all age groups. Respondents defined as meeting both aerobic-activity and muscle-strengthening guidelines reported moderate-intensity physical activity for ≥150 minutes per week, vigorous-intensity physical activity for ≥75 minutes per week, or an equivalent combination of moderate- and vigorous-intensity activity, and engaging in physical activities specifically designed to strengthen muscles at least twice per week. 

The percentage of adults aged ≥18yrs who met the aerobic-activity and muscle-strengthening guidelines increased from 18.2% in 2008 to 20.8% in 2013. Adults aged 18–44yrs were the most likely to meet the aerobic-activity and muscle-strengthening guidelines, and those aged ≥65yrs were the least likely in both 2008 and 2013. For all age groups, the percentage meeting the guidelines increased from 2008 to 2013.