Post-exercise recovery of autonomic cardiovascular control: a study by spectrum and cross-spectrum analysis in humans

Abstract

The recovery of the baseline autonomic control of cardiovascular activity after exercise has not been extensively studied. In 12 healthy subjects, we assessed the time-course of recovery by autoregressive spectrum and cross-spectrum analysis of heart period and systolic blood pressure during the 3 h after the end of 20 min of steady-state exercise at 50% (light workload, LW) and 80% (moderate workload, MW) of the individual's anaerobic threshold. The electrocardiogram and non-invasive blood pressure were simultaneously recorded during 10 min periods in the sitting position, at rest before exercise, and at 15, 60 and 180 min of recovery after exercise. At 15 min we observed a persistent tachycardia and relative hypotension; after MW, at 60 min heart rate was still slightly higher. Spectrum and cross-spectrum analysis showed, at 15 min, an increase in the low frequency component of systolic blood pressure, a reduction in the high frequency component of heart rate (larger in MW), and a decrease in baroreceptor sensitivity. After 60 and 180 min none of these parameters was significantly different from those at rest, although, in MW, some subjects still displayed signs of sympathetic activation after 1 h. We concluded that, after 15 min of recovery, the cardiovascular reflexes were blunted, that sympathetic nerve activity was still enhanced, and that the tone in the vagus had not fully recovered. Only the persistent vagal restraint seemed to be exercise intensity-dependent. For complete restoration of autonomic control after LW 1 h of rest was sufficient, and just enough after MW.

Effects of aerobic training intensity on resting, exercise and post-exercise blood pressure, heart rate and heart-rate variability

“…The current results show an elevated HR during the first 45 min of recovery compared with pre-exercise rest values, which is consistent with previous data, [36][37][38] but in contrast to Perini et al 18 With regard to the spectral components of HRV, we observed that the relative LF component in the recovery period was not different from pre-exercise rest values, [37][38][39] whereas the HF component during the recovery period was slightly lower than control. 37,38 We have not assessed HRV during exercise, but in an earlier study 40 in which we measured HRV during submaximal exercise (up to 40% of maximal workload), we found a slight increase of the relative LF component from 34 to 41%, and a pronounced decrease in the relative HF component from 32 to 9%. The slightly reduced HF component recorded post-exercise in comparison with the pre-exercise stage may indicate that parasympathetic withdrawal contributes to autonomic control of the post-exercise tachycardia.…”

Autonomic response to exercise as measured by cardiovascular variability

“…Published articles on the effect of exercise on the ANS as measured by HRV and BPV are summarised in three categories: the response of the ANS measured during a bout of exercise, 3,5,14,16,26,29,37,42,43,51 and directly after a bout of exercise (recovery measurements), 3,9,[22][23][24]28,40,49 and the long-term effect of regular exercise on the ANS. 4,8,[10][11][12][13]15,17,18,[19][20][21]25,27,[30][31][32][34][35][36]38,39,45,47 The results of 10 articles on ANS response measured during exercise are shown in Table I.…”

Heart rate variability is related to training load variables in interval running exercises

“…In addition, increased exercise intensity has been found to have an effect on HRV after exercise, both during early (Casties et al 2006;Goldberger et al 2006;Martinmäki & Rusko, 2008) and later recovery (Buchheit et al 2007a;Gladwell et al 2010;Parekh & Lee, 2005;Saboul et al 2015;Seiler et al 2007;Terziotti et al 2001).…”