Effects of aerobic exercise on ambulatory blood pressure responses to acute partial sleep deprivation: impact of chronotype and sleep quality

Blood pressure (BP) follows a circadian rhythm intertwined with the sleep-wake cycle. Acute partial sleep deprivation (PSD; sleep ≤6 hours) can increase BP, associated with increased cardiovascular risk. Acute exercise can reduce BP for up to 24-hours, a phenomenon termed post-exercise hypotension. The present study tested whether aerobic exercise could mitigate the augmented 24-hour ambulatory BP caused by acute PSD. Twenty-four young otherwise healthy adults (22 ± 3 years; 14 females; self-reported chronotypes: 6 early/10 intermediate/8 late; Pittsburgh sleep quality index: 17 good/7 poor sleepers) completed a randomized crossover trial where, on different days, they slept normally (2300-0700 hours), restricted sleep (0330-0700 hours [PSD]), and cycled for 50-minutes (70-80% predicted heart rate maximum) before PSD. Ambulatory BP was assessed every 30 minutes until 2100 hours the next day. Acute PSD increased 24-hour systolic BP (control: 117±9 mmHg, PSD: 122±9 mmHg, P<0.001) and prior exercise attenuated (exercise + PSD: 120±9 mmHg, P=0.04 vs. PSD), but did not fully reverse this response (exercise + PSD, P=0.02 vs. control). Subgroup analysis revealed that the 24-hour systolic BP reduction following exercise was specific to late types (PSD: 119±7 vs. exercise + PSD: 116±6 mmHg, P<0.05). Overall, habitual sleep quality was negatively correlated with the change in daytime systolic BP following PSD (r=-0.56, P<0.01). These findings suggest that the ability of aerobic cycling exercise to counteract the hemodynamic effects of acute PSD in young adults may be dependent on chronotype, and that habitual sleep quality can predict the daytime BP response to acute PSD.