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

Purpose 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. Methods Nineteen MetS patients (55.2 +/- 7.3 years, 6 women) entered the study. Eight of them were normotensive and eleven hypertensive according to MetS threshold (>= 130 mmHg for SBP and/or >= 85 mmHg for DBP). In the morning of 3 separated days, they underwent a cycling exercise bout of HIIT (> 90% of maximal heart rate, similar to 85% VO2max), or a bout of isocaloric moderate-intensity continuous training (MICT; similar to 70% of maximal heart rate, similar to 60% VO2max), or a control no-exercise trial (REST). After exercise, ambulatory blood pressure (ABP; 14 h) was monitored, while subjects continued their habitual daily activities wearing a wrist-band activity monitor. Results No ABP differences were found for normotensive subjects. In hypertensive subjects, systolic ABP was reduced by 6.1 +/- 2.2 mmHg after HIIT compared to MICT and REST (130.8 +/- 3.9 vs. 137.4 +/- 5.1 and 136.4 +/- 3.8 mmHg, 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 +/- 2.8 mmHg, respectively). Motion analysis revealed no differences among trials during the 14-h. Conclusion 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.