Author(s): BOULLOSA, D., WALTER-DA-SILVA-BARBOSA, G., OLIVEIRA-JUNIOR, S.A., MÜLLER, P.T., Institution: UNIVERSIDAD DE LEÓN, Country: SPAIN, Abstract-ID: 2629

INTRODUCTION:
Short sprint interval training (sSIT; ≤10-s efforts) is a time-efficient strategy known to induce rapid physiological adaptations. However, its cardiovascular effects in hypertensive adults remain unclear. This study examined the impact of a 2-week sSIT intervention (6 sessions) on cardiopulmonary and hemodynamic responses in hypertensive (HT) compared with normotensive (NT) adults.
METHODS:
Hypertensive (Stage 1; 29–63 yrs) and normotensive (27–59 yrs) adults completed six supervised cycling-based sSIT sessions over two weeks. A graded cardiopulmonary exercise test (starting at 25 W with 20 W·min⁻¹ increments) was performed before and after the intervention. Variables included rating of perceived exertion (RPE), peak oxygen uptake (VO₂peak), peak power output (Wpeak), and ventilatory efficiency (VE/VCO₂). Cardiovascular responses were assessed at rest and at a fixed submaximal workload (65 W), including heart rate (HR), blood pressure (BP), and rate-pressure product (RPP). Sprint load corresponded to 80% of pre-intervention Wpeak. Data were analyzed using two-way repeated-measures ANOVA (group × time).
RESULTS:
Peak power output (Wpeak) increased significantly in hypertensive (HT) participants only (interaction p=0.018), whereas VO₂peak showed no significant group × time interaction. Resting HR decreased in HT but not in NT (interaction p=0.016). Resting systolic BP decreased modestly in both groups (p=0.043), without interaction effect. At the fixed submaximal workload (65 W), HR was significantly reduced in HT only (interaction p<0.001). Peak VE/VCO₂ increased in HT, with no significant change in NT (interaction p=0.024). RPE for legs at peak exercise increased in HT but not in NT (interaction p<0.001).
CONCLUSION:
Six sessions of sSIT elicited rapid performance and cardiovascular adaptations in hypertensive adults without changes in VO₂peak. The reduction in resting and submaximal HR suggests improved cardiovascular regulation and reduced cardiac demand during exercise, while the increase in Wpeak indicates enhanced maximal work capacity. The observed increase in peak VE/VCO₂ and leg RPE likely reflects greater tolerance to high-intensity metabolic stress. These findings highlight the potential of low-volume sSIT as a time-efficient strategy to improve cardiovascular responses in hypertensive individuals.