Physical Activity in US Adults Compliance with the Physical Activity Guidelines for Americans

Background: To date, no study has objectively measured physical activity levels among U.S. adults according to the 2008 Physical Activity Guidelines for Americans (PAGA). Purpose: The purpose of this study was to assess self-reported and objectively measured physical activity among U.S. adults according to the PAGA. Methods: Using data from the NHANES 2005-2006, the PAGA were assessed using three physical activity calculations: moderate plus vigorous physical activity >= 150 minutes/week (MVPA); moderate plus two instances of vigorous physical activity >= 150 minutes/week (M2VPA); and time spent above 3 METs >= 500 MET-minutes/week (METPA). Self-reported physical activity included leisure, transportation, and household activities. Objective activity was measured using Actigraph accelerometers that were worn for 7 consecutive days. Analyses were conducted in 2009-2010. Results: U.S. adults reported 324.5 +/- 18.6 minutes/week (M +/- SE) of moderate physical activity and 73.6 +/- 3.9 minutes/week of vigorous physical activity, although accelerometry estimates were 45.1 +/- 4.6 minutes/week of moderate physical activity and 18.6 +/- 6.6 minutes/week of vigorous physical activity. The proportion of adults meeting the PAGA according to M2VPA was 62.0% for self-report and 9.6% for accelerometry. Conclusions: According to the NHANES 2005-2006, fewer than 10% of U.S. adults met the PAGA according to accelerometry. However, physical activity estimates vary substantially depending on whether self-reported or measured via accelerometer. (Am J Prev Med 2011;40(4):454-461) (C) 2011 American Journal of Preventive Medicine