Captopril Does Not Potentiate Post-Exercise Hypotension: A Randomized Crossover Study

To evaluate whether captopril (3 x 50 mg/day) potentiates post-resistance exercise hypotension (PREH) in hypertensives (HT), 12 HT men received captopril and placebo for 4 weeks each in a double-blinded, randomized-crossover design. On each therapy, subjects underwent 2 sessions: Control (C - rest) and Resistance Exercise (RE - 7 exercises, 3 sets to moderate fatigue, 50 % of 1 RM-repetition maximum). Measurements were taken before and after 30-60 min (Post1) and 7 h (Post2), and ambulatory blood pressure (BP) was monitored for 24 h. There were no differences in PREH characteristics and mechanisms between the placebo and captopril periods. At Post1, systolic/diastolic BP decreased significantly and similarly after RE with both therapies (Placebo = -13 +/- 2/ -9 +/- 1 mmHg vs. Captopril = -12 +/- 2/ -10 +/- 1 mmHg, P < 0.05). RE reduced cardiac output in some subjects and systemic vascular resistance in others. Heart rate and cardiac sympathetic modulation increased, while stroke volume and baroreflex sensitivity decreased after RE (Placebo: + 13 +/- 2 bpm, + 21 +/- 5 nu, -11 +/- 5 ml, -4 +/- 2 ms/mmHg; Captopril: + 13 +/- 2 bpm, + 35 +/- 4 nu, 17 +/- 5 ml, -3 +/- 1 ms/mmHg, P < 0.05). At Post2, all variables returned to pre-intervention values. Ambulatory BP was similar between the sessions. Thus, captopril did not potentiate the magnitude and duration of PREH in HT men, and it did not influence PREH mechanisms.