1 Department of Mathematics and Statistics, Concordia University, 1455 de Maisonneuve Blvd West, Montreal, QC H3G 1M8, Canada; PERFORM Centre, Concordia University, 7200 Sherbrooke St West, Montreal, QC H4B 1R6, Canada. Electronic address: lisa.kakinami@concordia.ca.
2 Department of Mathematics and Statistics, Concordia University, 1455 de Maisonneuve Blvd West, Montreal, QC H3G 1M8, Canada.
3 Department of Economics, Concordia University, 1455 de Maisonneuve Blvd West, Montreal, QC H3G 1M8, Canada.
4 Department of Epidemiology, Biostatistics and Occupational Health, McGill University, 1020 Pine Ave West, Montreal, QC H3A 1A2, Canada.
5 Centre de recherche du CHU Sainte-Justine, 5757 Ave Decelles, Montréal, QC H3S 2C3, Canada; INRS-Armand-Frappier Institute, 531 Boul des Prairies, Laval, QC H7V 1B7, Canada.
6 Research Centre of the Centre Hospitalier de l'Université de Montréal (CRCHUM), 900 St Denis St, Montreal, QC H2X 0A9, Canada; École de santé publique, Université de Montréal (ESPUM), PO Box 6128, Downtown Station, Montreal, QC H3C 3J7, Canada.

The objective of this study was to determine whether the relationship between income and leisure-time physical activity (LTPA) persists after accounting for a person's utilitarian PA (all non-LTPA), sociodemographic characteristics and transportation PA. Data were from eight cycles (1999-2014) of the nationally representative samples of the US adult population from the National Health and Nutrition Examination Survey (n = 35,239). Whether the poverty income ratio (0-1.3, 1.3-1.86, 1.86+ [reference]) was associated with minutes of LTPA (moderate, vigorous) after stratifying for utilitarian PA (sedentary, light, moderate, and vigorous) was assessed in multiple linear regressions adjusted for age, sex, race, education, marital status, weight status, hours worked, and minutes of transportation-related PA in the past week. Likelihood of meeting national physical activity recommendations was also assessed in multiple logistic regressions adjusting for the covariates described. For both sedentary and light utilitarian PA levels, compared to the reference, persons living in households of the lowest poverty income ratio were consistently associated with approximately 17-30 less minutes of moderate LTPA minutes per week, and 20-25 less minutes of vigorous LTPA across all survey cycles. Compared to the reference, the likelihood of meeting national PA recommendations was approximately 31-55% less for these households. The known association between lower income and lower LTPA persist, but is the most persistent and consistent for those with less active utilitarian (such as sedentary) lifestyles. Interventions aimed at increasing LTPA among people with low income and sedentary utilitarian lifestyles whether or not they are in the workforce are particularly needed.