Postexercise Hypotension After Moderate-Intensity Continuous and High-Intensity Interval Exercise

Abstract

Moderate-intensity exercise has been shown to lower blood pressure (BP) in the postexercise setting. However, the effects of shorter, high-intensity interval exercise sessions on postexercise hypotension (PEH) are unknown. PURPOSE: To compare postexercise BP responses after moderate-intensity continuous exercise and two different types of high-intensity interval exercise. METHODS: Eleven healthy subjects (10 male, 1 female; Age = 25.5 + 3.7 years; VO2peak = 44.9 + 7.5 ml/kg/min; SBP = 124.4 + 20.9 mmHg, DBP = 67.6 + 6.9 mmHg) underwent, in randomized order, one control (CON) trial and three exercise conditions on a cycle ergometer: moderate-intensity continuous exercise [MOD; 80% HRmax for 30 min], aerobic interval exercise [AIE; 4 × 4-min bouts at 90-95% HRmax separated by 3 min of active recovery], and sprint interval exercise [SIE; 6 "all-out" 30-sec sprints (Wingate tests) separated by 4 min active recovery]. Seated BP was measured with an automated oscillometric BP cuff prior to the start of exercise and at 15-min intervals for 3 hr postexercise. Mixed model analysis was used to examine the differences in blood pressure following the exercise bouts. Post-hoc testing was carried out to examine pair-wise comparisons. RESULTS: All exercise conditions resulted in a significant PEH. The mean (+SD) SBP during the 3-hr postexercise period was significantly (p< 0.05) lower after AIE than CON (-6.4 + 0.9 mmHg), MOD (-4.1 + 0.9 mmHg), and SIE (-3.7 + 0.9 mmHg). SIE and MOD resulted in equivalent and significant SBP reductions as compared to CON (-2.7 + 0.9 and -2.3 + 0.9 mmHg; p < 0.05). Mean DBP during the 3-hr postexercise period was also lower (p< 0.05) after AIE compared to CON (-3.6 + 0.6 mmHg), MOD (-2.8 + 0.6 mmHg), and SIE (-1.6 + 0.6 mmHg); DBP was also lower after SIE compared to CON (-1.9 + 0.6 mmHg). CONCLUSIONS: Aerobic interval exercise resulted in superior reductions in both SBP and DBP as compared to SIE and MOD for up to three hours postexercise. AIE was well tolerated and may be a useful exercise strategy to help lower BP in otherwise healthy young adults. Extremely high-intensity sprint-type exercise (e.g., Wingate) is not necessary to maximize PEH.