Trends in Aerobic and Muscle-Strengthening Physical Activity by Race/Ethnicity Across Income Levels Among US Adults, 1998-2018.

Background: Although disparities in leisure-time physical activity (LTPA) participation by race/ethnicity and income are known, the combined association of these characteristics with LTPA participation is less understood. This study aims to describe trends and determine whether racial/ethnic differences in adult physical activity by income level have changed over the past 2 decades.
Methods: The authors estimated LTPA participation (outcomes: any aerobic activity, meeting the aerobic activity guideline, meeting the muscle-strengthening guideline, and meeting the combined aerobic and muscle-strengthening guidelines) among adults ≥18 years by race/ethnicity across income levels using 1998-2018 National Health Interview Survey data in 3-year aggregates. They also tested for trends, prevalence differences, and difference in differences using logistic regression.
Results: LTPA participation increased from 1998-2000 to 2016-2018 for all outcomes for non-Hispanic white, non-Hispanic black, and Hispanic adults at all income levels. Disparities narrowed for some groups but persisted between white and racial/ethnic minority groups across income levels for engaging in any aerobic activity and meeting the aerobic guideline (0.2-8.8 percentage point difference in differences). Disparities in meeting the muscle-strengthening and combined guidelines were less common.
Conclusions: Opportunities exist to ensure that adults, particularly members of lower income racial/ethnic minority groups, have support to help them participate in LTPA.