Similar Postexercise Hypotension After MICT, HIIT, and SIT Exercises in Middle-Age Adults

Abstract

Introduction: Acute bouts of moderate-intensity continuous training (MICT) and high-intensity interval training (HIIT) transiently lower systolic blood pressure (SBP) and diastolic blood pressure (DBP) in the hours after termed postexercise hypotension (PEH); however, the effects of sprint interval training (SIT) exercise have yet to be explored in middle-age adults. Although previous work has found no effect of exercise intensity on PEH, no study has compared submaximal, near maximal, and supramaximal intensities, specifically in middle-age adults where blood pressure (BP) management strategies may be of greater importance.

Purpose: This study examined the effects of MICT, HIIT, and SIT exercises on PEH in the immediate (≤2 h) and 24 h after exercise specifically in middle-age adults.

Methods: Fourteen participants (10 female; age, 46 ± 9 yr; SBP, 116 ± 11 mm Hg; DBP, 67 ± 6 mm Hg; one hypertensive, four prehypertensive, nine normotensive) had their BP measured before, immediately (15, 30, 60, 120 min), and over 24 h after four experimental sessions: 1) 30-min MICT exercise (65% maximal oxygen consumption), 2) 20-min HIIT exercise (10 × 1 min at 90% maximum heart rate with 1-min rest), 3) 16-min SIT exercise (8 × 15 s all-out sprints with 2-min rest), and 4) no-exercise control. Postexercise BP was compared with no-exercise control.

Results: PEH was similar for all exercise sessions for SBP ( P = 0.388, = 0.075) and DBP ( P = 0.206, = 0.108). Twenty-four-hour average SBP was similar for all sessions P = 0.453, = 0.069), and DBP was similar over 24 h except after MICT exercise compared with HIIT exercise ( P = 0.018, d = 1.04).

Conclusions: In middle-age adults, MICT, HIIT, and SIT exercises are effective at reducing SBP; however, the effects on DBP are smaller, and neither reductions are sustained over 24 h.