Characteristics of post-exercise responders versus non-responders following aerobic or isometric exercise in physically inactive adults of African and South Asian descent with high-normal blood pressure or grade I hypertension

Objective To investigate interindividual variability in post-exercise hypotension (PEH) and to characterize cardiovascular and autonomic differences between responders and non-responders following aerobic and isometric exercise in adults of African and South Asian descent with elevated blood pressure (BP).Methods Physically inactive adults of African and South Asian descent living in Suriname (18–65 years) with high-normal BP or grade I hypertension participated in a randomized controlled crossover trial. In this randomized cross-over trial, 47 adults (50.1 ± 10.8 years; 38% male) with high-normal blood pressure or grade I hypertension completed three conditions: aerobic exercise (30 min at 40–60% heart rate reserve), isometric handgrip exercise, and a non-exercise control. Ambulatory BP was assessed over 24 hours. PEH was defined as the net effect: (post-exercise – pre-exercise) – (post-control – pre-control). Participants were classified as responders if daytime BP decreased ≥5 mmHg. Arterial stiffness, cardiac, and autonomic parameters were assessed.Results Following aerobic exercise, 46% of participants were classified as systolic responders compared with 28% after isometric exercise. No baseline differences were observed in demographic or clinical characteristics between responders and non-responders, suggesting that PEH variability may reflect underlying physiological rather than clinical differences. Aerobic responders demonstrated greater reductions in aortic augmentation index (−19.4% vs −10.9%, p = 0.05), larger increases in stroke volume (+8.1 vs −5.3 mL, p = 0.05) and cardiac output (+1.54 ± 1.89 vs +0.58 ± 1.60 L/min, p = 0.009), and more favorable autonomic recovery. Among all variables, only the change in cardiac output was associated with PEH magnitude (r = −0.46, p = 0.006). No consistent physiological differences were observed following isometric exercise.Conclusion PEH following aerobic exercise is characterized by a distinct responder phenotype associated with greater reductions in aortic augmentation index and favorable cardiac adaptations. These findings highlight substantial interindividual variability in BP responses and support the need for individualized exercise strategies in hypertension management