Physical activity moderates the effects of daily psychosocial stressors on ambulatory blood pressure

Abstract

Objective: Previous literature has shown an inconsistent relationship between physical activity and stressor-evoked blood pressure reactivity. Use of ecological momentary assessment (EMA) may facilitate detecting such a relationship. In this study, the moderating effects of regular physical activity on the magnitude of ambulatory blood pressure (ABP) responses to psychosocial stressors experienced in daily life were examined.

Method: Four hundred seventy-seven healthy working adults (ages 30-54) provided ABP readings and recorded their daily experiences, using electronic diaries (ED), over 4 monitoring days. Measures of momentary Task Strain (high demand, low control) and Social Conflict (rating of recent social interaction quality) were used as indices of stressor exposure, and an accelerometry device was used to create 2 indices of physical activity: weekly average and recent (30 min prior to each ED interview). Multilevel models were used to examine the moderating between- and within-person effects of physical activity on ABP fluctuations corresponding with the momentary psychosocial stressors.

Results: Weekly physical activity moderated the effects of ABP responses to Task Strain (systolic blood pressure [SBP]: p = .033; diastolic blood pressure [DBP]: p = .028) and Social Conflict (DBP: p = .020), with significant increases in SBP and DBP shown for less physically active individuals but not for more physically active individuals. Similarly, recent physical activity moderated within-person DBP responses to Task Strain (p = .025), with greater DBP increases following less active periods.

Conclusion: Our results demonstrate that weekly and recent physical activity may moderate the effects of ABP responses to daily psychosocial stress. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Figure 1.

Person-level weekly physical activity as a moderator of the relationship between Ambulatory SBP and DBP Reactivity to Task Strain. N = 463 with complete data. Figures present the data where physical activity measures are centered one standard deviation above (higher activity) and below (lower activity) the sample mean (M = 1.62, SD = 0.29). Data are further stratified by periods of task strain (high demand, low control) versus no task strain. Covariates in this model include sex, age, race, education, and 14 time-varying covariates: standing, sitting, speaking, comfort level (too cold, too hot), recent consumption of meal, snack, caffeine, alcohol, or cigarettes, self-reported physical activity (light, moderate, and vigorous), and metabolic equivalent (METs) in the prior 10 minutes.

Figure 2.

Person-level weekly physical activity as a moderator of the relationship between Ambulatory SBP and DBP Reactivity to Social Conflict. N = 417 with complete data. Figures present the data where physical activity is centered one standard deviation above (higher activity) and below (lower activity) the sample mean (M = 1.62, SD = 0.28), and Social Conflict is centered one standard deviation above (high conflict) and below (low conflict) the sample mean (M = 1.65, SD = 0.91). Covariates in this model include sex, age, race, education, and 14 time-varying covariates: standing, sitting, speaking, comfort level (too cold, too hot), recent consumption of meal, snack, caffeine, alcohol, or cigarettes, self-reported physical activity (light, moderate, and vigorous), and metabolic equivalent (METs) in the prior 10 minutes.

Figure 3.

Momentary-level recent physical activity as a moderator of the relationship between Ambulatory SBP and DBP Reactivity and Task Strain. N = 463 with complete data. Figures present the data where physical activity measures are centered one standard deviation above (higher activity) and below (lower activity) the sample mean (M = 1.62, SD = 0.71). Data are further stratified by periods of task strain (high demand, low control) versus no task strain. Covariates in this model include average weekly physical activity and 14 time-varying covariates: standing, sitting, speaking, comfort level (too cold, too hot), recent consumption of meal, snack, caffeine, alcohol, or cigarettes, self-reported physical activity (light, moderate, and vigorous) and metabolic equivalent (METs) in the prior 10 minutes.