Objective: In this pilot clinical study we investigated the effect on blood pressure (BP) of two community-based exercise training programs of high (HIT) vs. low-moderate intensity (LMIT) in hypertensive individuals receiving at least one antihypertensive drug.
Methods: The study included two phases of physical exercises based on 1-h session, 3 days/week for 12 and 16 weeks, respectively, separately by a 7-week resting period. Each phase was preceded by a four-week conditioning training period. According to the average maximal heart rate at baseline, participants were randomized to HIT (80-90%), LMIT (50-70%) or no-exercise (control). Heart rate was monitored during workout and BP profiles were registered by ambulatory BP monitoring at the beginning and end of each phase.
Results: Of 60 individuals randomized, 44 completed the study (HIT, n = 10; LMIT, n = 16; controls, n = 18). BP levels were significantly reduced after the second phase for both LMIT (SBP -3.1 mmHg, DBP -2.4 mmHg) and HIT (SBP -10.8 mmHg, DBP -8.3 mmHg). Similar levels of improvement were also found in daytime and night-time BP. Mean attendance of the prescribed training sessions was 87.4 ± 6.2% for HIT and 87.4 ± 5.3% for LMIT during the first phase and 84.1 ± 5.0% and 85.2 ± 5.9% during the second phase, respectively (p = 0.047).
Conclusion: Both HIT and LMIT exercise training programs reduced BP but the HIT modality showed a lower rate of compliance with proposed training schedule. Intensity of training should be individually prescribed to improve tolerance to more high intensity exercises.
Keywords: blood pressure monitoring; hypertension; physical exercises; primary care; training intensity.