Moderate aerobic training improves autonomic cardiovascular control in older women

The decline in the cardiovascular autonomic regulation in advanced age is considered a risk factor for several cardiovascular diseases. We tested, on eleven healthy untreated women aged 60-70 years, whether a six-month period of group-based training exerts positive effects on this age-associated decline. Before and after training, ECG and arterial pressure (Finapres) were recorded in supine position. We calculated mean values +/- SEM of R-R period (RR), systolic (SAP) and diastolic (DAP) arterial pressure, as well as, by autoregressive spectral analysis methods, low (approximately 0.1 Hz) and high (respiratory) frequency oscillations of RR (LF(RR), HF(RR)) and SAP (LF(SAP), HF(SAP)), and the baroreflex sensitivity (BRS). Training induced statistically significant changes (p < 0.05 by paired t-test): increase in RR (mean +/- SEM) from 894 +/- 41 to 947 +/- 31 ms and in heart rate variability (HRV) by 25 %, decrease in DAP from 75.8 +/- 3.0 to 70.8 +/- 2.2 mmHg, no change in SAP. LF(RR) and LF(SAP) increased by more than 100%, while BRS by 32%. We suggest that the increase in BRS might be responsible for the observed bradycardia and higher LF(RR). An improved modulation, rather than an increase, in tonic sympathetic activity, is also suggested. A specific program of moderate aerobic training is adequate to increase the BRS and the HRV in older women.