More moderate-intensity physical activity and less prolonged sedentary time are associated with better very short-term systolic blood pressure variability in healthy adults.

Whole-day movement guidelines for improving health, recommend that adults engage in at least 150 min week of moderate-to-vigorous aerobic physical activity and limit their sedentary time. In young adults, higher systolic blood pressure variability (BPV) is a precursor for the development of hypertension. The impact of habitual activity that comprises (inter)national guidelines on BPV is unclear. We tested the hypothesis that less habitual physical activity and greater sedentary time would be associated with larger BPV. Ninety-two normotensive participants [age: 19-38 years, body mass index (BMI): 23.6 ± 3.3 kg/m, 44♀] wore an activPAL monitor on their thigh for 7.0 ± 0.3 days. Ten minutes of supine systolic arterial pressure was measured via finger photoplethysmography (115 ± 11 mmHg). Beat-by-beat systolic BPV was measured using the average real variability index (1.1 ± 0.6 mmHg). Relationships between habitual activity outcomes and BPV were assessed via multiple regressions adjusted for age, sex, and BMI. Moderate-intensity physical activity (average: 36 ± 19 min day; β = -0.010, p = 0.02) and time spent in sedentary bouts >1-h (245 ± 134 min day; β = 0.002, p < 0.001), but not light-intensity activity, vigorous-intensity activity, standing time, sedentary breaks, or time spent in sedentary bouts <1-h (all, p > 0.10) were predictors of systolic BPV. Higher moderate physical activity and lower prolonged sedentary time were associated with attenuated systolic BPV responses in young adults. These findings highlight the cardiovascular benefits of habitual activity among younger adults and suggest that simple strategies such as reducing long periods of uninterrupted sitting and increasing moderate-intensity physical activity may be efficacious for reducing the risk of developing or delaying the onset of hypertension.