Post-concurrent exercise hemodynamics and cardiac autonomic modulation

Abstract

Concurrent training is recommended for health improvement, but its acute effects on cardiovascular function are not well established. This study analyzed hemodynamics and autonomic modulation after a single session of aerobic (A), resistance (R), and concurrent (A + R) exercises. Twenty healthy subjects randomly underwent four sessions: control (C:30 min of rest), aerobic (A:30 min, cycle ergometer, 75% of VO(2) peak), resistance (R:6 exercises, 3 sets, 20 repetitions, 50% of 1 RM), and concurrent (AR: A + R). Before and after the interventions, blood pressure (BP), heart rate (HR), cardiac output (CO), and HR variability were measured. Systolic BP decreased after all the exercises, and the greatest decreases were observed after the A and AR sessions (-13 ± 1 and -11 ± 1 mmHg, respectively, P < 0.05). Diastolic BP decreased similarly after all the exercises, and this decrease lasted longer after the A session. CO also decreased similarly after the exercises, while systemic vascular resistance increased after the R and AR sessions in the recovery period (+4.0 ± 1.7 and +6.3 ± 1.9 U, respectively, P < 0.05). Stroke volume decreased, while HR increased after the exercises, and the greatest responses were observed after the AR session (SV, A = -14.6 ± 3.6, R = -22.4 ± 3.5 and AR = -23.4 ± 2.4 ml; HR, A =+13 ± 2, R =+15 ± 2 vs. AR =+20 ± 2 bpm, P < 0.05). Cardiac sympathovagal balance increased after the exercises, and the greatest increase was observed after the AR session (A = +0.7 ± 0.8, R = +1.0 ± 0.8 vs. AR = +1.2 ± 0.8, P < 0.05). In conclusion, the association of aerobic and resistance exercises in the same training session did not potentiate post-exercise hypotension, and increased cardiac sympathetic activation during the recovery period.

Continuous and Accumulated Bouts of Cycling Matched by Intensity and Energy Expenditure Elicit Similar Acute Blood Pressure Reductions in Prehypertensive Men

“…Regarding postexercise cardiac autonomic control, our findings agree with previous reports (13,14,39,43), since the HRV spectral analysis indicated that during recovery from continuous and accumulated cycling bouts, sympathetic activity (LF band) increased while parasympathetic activity (HF band) decreased, resulting in higher sympathovagal balance (LF:HR ratio) concomitant with a reduction in blood pressure (see Figures 1 and 2). Moreover, the acute reductions in blood pressure following CONTIN and INTER2 were negatively correlated with changes in sympathovagal balance, meaning that the greater the magnitude of PEH, the greater the increase in relative sympathetic activity (see Figure 3).…”

“…Changes in autonomic cardiac control, as measured by heart rate variability (HRV) and reflecting beat-tobeat changes in HR and the sympathovagal interaction obtained by the variation of both instantaneous HR and R-R intervals within the cardiac cycle (42), seem to influence blood pressure after exercise (7,43). It is known that blood pressure is determined by the relationship between cardiac output (Q) and systemic vascular resistance (SVR), cardiac (central) or vascular (peripheral) mechanisms that reflect changes in central regulation (8), leading to attenuation of the blood pressure response in the postexercise recovery.…”

“…Some studies suggest decreased sympathetic activity and increased parasympathetic activity concomitant to PEH (33), while others suggest a compensatory increase in sympathetic activity would occur to offset the blood pressure reduction and baroreflex resetting (13,14,39,43), or that no changes would occur (3,32). The extent to which PEH accompanies a shift in cardiac autonomic balance therefore remains unclear and requires further investigation.…”

Influência do grupamento muscular na recuperação da frequência cardíaca após o exercício resistido

“…The exercise intensity is one of the most investigated variables and which mostly influences on the cardiovascular responses during the RE 8,20 . The intensity used in the present study (80% of 1RM), despite being recommended for muscle strength improvement in weight lifters and individuals experienced in resistance training 1 , it promotes higher alteration in the autonomic balance 8 , leading to slower REC-HR 9 . However, even in the high intensity, other factors may alter the autonomic responses and, in the present study, it was observed that the muscle group also influences on these responses.…”

“…Despite the benefits of RE practice, the acute metabolic and mechanical stimulus which occurs during a RE session promotes cardiovascular stress and alteration in the cardiac autonomic balance; that is, decrease of vagal activity and increase of cardiac sympathetic activity [7][8][9] . These responses increase heart rate (HR) with the aim to meet the increased blood demand in the active musculature.…”