DOI 10.1007/s00421-006-0257-yORIGINAL ARTICLE Post-resistance exercise hypotension, hemodynamics, and heart rate variability: inXuence of exercise intensity

Abstract The occurrence of post-exercise hypoten-sion after resistance exercise is controversial, and its mechanisms are unknown. To evaluate the eVect of diVerent resistance exercise intensities on post-exercise blood pressure (BP), and hemodynamic and auto-nomic mechanisms, 17 normotensives underwent three experimental sessions: control (C—40 min of rest), low- (E40%—40 % of 1 repetition maximum, RM), and high-intensity (E80%—80 % of 1 RM) resistance exer-cises. Before and after interventions, BP, heart rate (HR), and cardiac output (CO) were measured. Auto-nomic regulation was evaluated by normalized low-(LFR–Rnu) and high-frequency (HFR–Rnu) components of the R–R variability. In comparison with pre-exer-cise, systolic BP decreased similarly in the E40 % and E80 % (¡6 § 1 and ¡8 § 1 mmHg, P < 0.05). Diastolic BP decreased in the E40%, increased in the C, and did not change in the E80%. CO decreased similarly in all the sessions (¡0.4 § 0.2 l/min, P < 0.05), while systemic vascular resistance (SVR) increased in the C, did not change in the E40%, and increased in the E80%. Stroke volume decreased, while HR increased after both exercises, and these changes were greater in the E80 % (¡11 § 2 vs. ¡17 § 2 ml/beat, and +17 § 2 vs. +21 § 2 bpm, P < 0.05). LFR–Rnu increased, while ln HFR–Rnu decreased in both exercise sessions. In conclusion: Low- and high-intensity resistance exer-cises cause systolic post-exercise hypotension; how-ever, only low-intensity exercise decreases diastolic BP. BP fall is due to CO decrease that is not compen-sated by SVR increase. BP fall is accompanied by HR increase due to an increase in sympathetic modulation to the heart