Is Physical Activity Associated with Patterns of Stress-Related Brain Activity and Daily Life Stress Reactivity in Midlife Adults?

The purpose of this research project is to answer three questions. First, we are attempting to replicate our previous finding (Thomas et al., 2019) which showed that people who are more physically activity show attenuated blood pressure responses to daily life stress compared to those who are not. Second, we are examining, for the first time, whether those who are more physically active also show patterns of attenuated stress-related brain activation. And third, we will be examining whether attenuated patterns of stress-related brain activation account for any association seen between physical activity and attenuated blood pressure responses to daily life stress (that is, whether the observed association between physical activity and stress responses can be indirectly explained by associations involving stress-related brain activation). We will be examining these questions in a sample of midlife adults (ages 28-56). The following hypotheses will be tested. • H1: Across individuals, those who engage in more physical activity during daily life will exhibit smaller changes in ambulatory blood pressure when they are exposed to daily life stress, compared to those who are more relatively sedentary. • H2: Across individuals, those who engage in more physical activity during daily life will also exhibit a pattern of brain activation during stress which is consistent with a smaller magnitude of stress-related responding. • H3: Across individuals, the association between daily physical activity and stress-related ambulatory blood pressure reactivity will be partially accounted for (i.e., statistically mediated by) the pattern of stress-related brain activation that characterizes those who engage in more physical activity.