Ambulatory blood pressure reduction following 2 weeks of high-intensity interval training on an immersed ergocycle

Background. - Hypertension guidelines recommend moderate-intensity continuous training (MICT) for the primary or secondary prevention of hypertension. However, alternative modalities, such as high-intensity interval training (HIIT) on dry land or in water, have been studied less widely. Aim. - To assess chronic blood pressure (BP) response to a 2-week training programme involving six sessions of either MICT or HIIT performed on dry land or HIIT performed in an immersed condition, in participants with baseline office systolic/diastolic BP (SBP/DBP) >= 130/85 mmHg. Methods. - We randomly assigned 42 individuals (mean age 65 +/- 7 years; 52% men) with baseline office SBP/DBP >= 130/85 mmHg to perform six 24-minute sessions on an ergocycle (three times a week for 2 weeks) of either MICT on dry land, HIIT on dry land or HIIT in a swimming pool, and assessed BP responses using 24-hour ambulatory BP monitoring. Results. - While 2-week MICT and HIIT on dry land modified none of the 24-hour average haemodynamic variables significantly, immersed HIIT induced a significant decrease in 24-hour BP (SBP -5.1 +/- 7.3 [P= 0.02]; DBP -2.9 +/- 4.1 mmHg [P= 0.02]) and daytime BP (SBP -6.2 +/- 8.3 [P= 0.015]; DBP -3.4 +/- 4.0 mmHg [P= 0.008]), and slightly improved 24-hour and daytime pulse wave velocity (PWV) (24-hour PWV -0.17 +/- 0.23 m/s [P= 0.015]; daytime PWV -0.18 +/- 0.24 m/s [P= 0.02]). Conclusion. - HIIT on an immersed stationary ergocycle is an innovative method that should be considered as an efficient non-pharmacological treatment of hypertension. As such, it should now be implemented in a larger cohort to study its long-term effects on the cardiovascular system. (C) 2019 Elsevier Masson SAS. All rights reserved.