We aimed to compare prolonged hypotension following moderate-intensity continuous exercise (MICE), high-intensity interval exercise (HIIE) in dry land or HIIE in immersed condition, using 24-h ambulatory blood pressure monitoring (ABPM).Design and method:
Forty-two individuals (Table 1) suffering from hypertension or with a baseline blood pressure (BP) > = 130/85 mmHg (systolic/diastolic, SBP/DBP), were randomly assigned to performing one of the three following exercises on a stationary cycle: MICE (24-min at 50% peak power output (PPO)) or HIIE in dry land (two sets of 10-min with phases of 15-sec at 100% PPO interspersed by 15-sec of passive recovery) or HIIE in up-to-the-chest immersed condition. ABPM and ambulatory pulse wave velocity (PWV) were assessed during the 24-h after.Results:
While MICE modified none of the 24-h average hemodynamic variables, dryland HIIE induced a 24-h BP decrease (SBP: −3.6 ± 5.7 / DBP: −2.8 ± 3.0 mmHg, P < 0.05) and, to a much greater extent, immersed HIIE (SBP: −6.8 ± 9.5 / DBP: −3.0 ± 4.5 mmHg, P < 0.05). The one condition that modified 24-h PWV was immersed HIIE (−0.21 ± 0.30 m/s, P < 0.05).Conclusions:
HIIE performed on a stationary cycle in immersed condition, appeared more effective than HIIE in dry land and MICE in improving 24-h ABPM. In addition, cycling in water alleviated 24-h arterial stiffness.