Differential Effects of Twice vs. Four Times Weekly Combined Exercise Training in Aging Adults With Hypertension: A Randomized Clinical Trial.

Current exercise guidelines emphasize a total weekly volume of exercise (i.e., 150 min/week), but the optimal weekly frequency remains uncertain. Therefore, this randomized clinical trial aimed to compare the effects of combined resistance and aerobic training either two or four times per week, at the same total weekly volume, on office and ambulatory blood pressure in older adults with hypertension. Participants were randomized to exercise training performed either twice per week (CT2, n = 49) or four times per week (CT4, n = 49), for 12 weeks. Primary outcome was 24-h ambulatory BP; secondary outcomes included office BP and physical fitness, assessed at baseline and post-intervention. Of the 98 randomized participants (66% women; mean age 64 ± 7 years), all were included in the intention-to-treat analysis, whereas 63 were retained for the per-protocol analysis after excluding those with low adherence (< 80%) or missing post-intervention data. Although no significant differences between groups were observed in office and ambulatory BP in the intention-to-treat analysis, office systolic (-8 mmHg, p = 0.001) and diastolic BP (-3 mmHg, p = 0.001) reduced in CT4 (-8 mmHg, p = 0.001), and systolic BP decreased in CT2 after training (-4 mmHg, p = 0.032). In the per-protocol analysis, office systolic BP was lower in CT4 than CT2 after training (-6 mmHg, p = 0.049). CT4 demonstrated significant reductions in 24-h systolic (-4 mmHg, p = 0.012) and diastolic BP (-2 mmHg, p = 0.010) after training. Cardiorespiratory fitness improved in CT4 (Δ = 8%, p < 0.001) but not in CT2. Our findings suggest that higher weekly frequency may optimize blood pressure management in hypertension, although these additional benefits appear to be dependent on high protocol adherence. Trial Registration: ClinicalTrials.gov Identifier: NCT04218903.