Effect of time of exercise and posture on 24-h post-exercise blood pressure in young normotensive men

This study aimed to examine blood pressure (BP) response in sitting (daytime only) and supine positions for 24 h after moderate endurance exercise in the morning and afternoon in healthy and normotensive young men. Nine men with a moderate fitness level ran at 68%-69% maximal oxygen uptake for 30 min at 8:00 AM and 4:00 PM. Arterial BP was measured hourly for 24 h after each exercise and each control experiment. The positions during the measurement were supine during nighttime, and supine and sitting during daytime (7:00 AM-11:00 PM). The Profile of Mood States (POMS) test was performed before the sitting measurement. Post-exercise systolic BP (SBP) in the supine position decreased by 2-3 mmHg on average for 24 h in both exercise conditions compared to the control condition (p < 0.05). In both exercise conditions, the post-exercise SBP decrease tended to be smaller in the sitting than in the supine position, and a greater SBP decrease in the sitting position tended to relate linearly with a greater fatigue score increase. We conclude that, in young normotensive men, a bout of moderate endurance exercise both in the morning and afternoon decreases SBP in the supine position by a few mmHg on average over 24 h. In addition, post-exercise BP response during daytime appeared to vary with posture and relate to fatigue sensation.