Ambulatory blood pressure response to a bout of HIIT in metabolic syndrome patients.

Abstract

The effectiveness of exercise to lower blood pressure may depend on the type and intensity of exercise. We study the short-term (i.e., 14-h) effects of a bout of high-intensity aerobic interval training (HIIT) on blood pressure in metabolic syndrome (MetS) patients. Nineteen MetS patients (55.2±7.3years, 6 women) entered the study. Eight of them were normotensive and eleven hypertensive according to MetS threshold (≥130mmHg for SBP and/or ≥85mmHg for DBP). In the morning of 3 separated days, they underwent a cycling exercise bout of HIIT (>90% of maximal heart rate, ~85% VO2max), or a bout of isocaloric moderate-intensity continuous training (MICT; ~70% of maximal heart rate, ~60% VO2max), or a control no-exercise trial (REST). After exercise, ambulatory blood pressure (ABP; 14h) was monitored, while subjects continued their habitual daily activities wearing a wrist-band activity monitor. No ABP differences were found for normotensive subjects. In hypertensive subjects, systolic ABP was reduced by 6.1±2.2mmHg after HIIT compared to MICT and REST (130.8±3.9 vs. 137.4±5.1 and 136.4±3.8mmHg, respectively; p<0.05). However, diastolic ABP was similar in all three trials (77.2±2.6 vs. 78.0±2.6 and 78.9±2.8mmHg, respectively). Motion analysis revealed no differences among trials during the 14-h. This study suggests that the blood pressure reducing effect of a bout of exercise is influence by the intensity of exercise. A HIIT exercise bout is superior to an equivalent bout of continuous exercise when used as a non-pharmacological aid in the treatment of hypertension in MetS.