Emerging adults without a driver's license engage in more transportation-related physical activity to school/work in certain environmental contexts.

The aim was to examine the moderation effect of driving licensure status on the association between different environmental contexts and transportation-related physical activity to and from school and/or work (TPA-SW) among emerging adults. The data were from Wave 4 (n=2026, year 2013) of the NEXT Generation Health Study, an annual assessment of a nationally representative cohort across the nine U.S. Census Divisions. The outcome variable, TPA-SW, was derived from walking or cycling as modes of travel to and from school and/or work. Environmental context variables included residence, college attendance, and work status. Driving licensure status indicated whether or not participants had an independent driver's license. Poisson regression models, adjusted for potential confounders, were used to test interactions between environmental context and driving licensure. There were significant interactions between environmental context and licensure. Interaction contrasts indicated that participants who did not have a driver's license engaged in more TPA-SW than their licensed counterparts if they were living at home (β=1.10, p<0.001), not attending school (β=0.73, p<0.001), attending a technical school/community college (β=1.13, p<0.001), working 1-30 hours/week (β=0.69, p<0.001), or working 30+hours/week (β=1.12, p<0.001). Among non-workers, those without a license engaged in less TPA-SW than participants with a license (β=-0.22, p=0.05). Among emerging adults in certain environmental contexts, delayed driver licensing may result in more physical activity with the possible tradeoff of less transportation mobility.