Istituto di Ricovero e Cura a Carattere Scientifico San Raffaele Pisana, Rome, Italy.
Int J Cardiol. 2013 Jun 20;166(2):334-9. doi: 10.1016/j.ijcard.2011.10.082. Epub 2011 Nov 9.
Heart Rate Variability (HRV) and Baroreflex Sensitivity (BRS) are impaired in patients with Chronic Heart Failure (CHF) and carry negative prognosis. Exercise training improves these parameters. However, the relationship between exercise training with HRV and BRS has been investigated without regard for individual training loads. We tested the hypothesis that in CHF patients changes in HRV and BRS are dose-response related to individual volume/intensity training load (TL).
Twenty patients with stable postinfarction CHF under optimal medical treatment were randomized to either aerobic continuous training (ACT) or aerobic interval training (AIT) for 12weeks. Individualized TL was monitored by the Training Impulses (TRIMPi) method, which was determined using the individual HR and lactate profiling determined during a treadmill test at baseline. HRV (standard deviation of mean R-R interval) and BRS were assessed at rest and 3weeks apart, throughout the study.
HRV, BRS and R-R interval increased significantly with training, being very highly correlated to the dose of exercise with a second-order regression model (r(2) ranged from 0.75 to 0.96; P<0.001), resembling a bell-shaped in the ACT, and an asymptotic-shaped curve in the AIT groups, respectively. These changes were accompanied by a significant increase in functional capacity. No significant differences were detected between ACT and AIT in any variable.
These results suggest that improvements in HRV and BRS by exercise training in CHF patients are dose related to TL in a non-linear fashion on an individual basis, with optimal results at moderate doses of exercise.
心率变异性（HRV）和压力反射敏感性（BRS）在慢性心力衰竭（CHF）患者中受损，并且具有负面预后。运动训练可以改善这些参数。然而，对于个体训练负荷，运动训练与 HRV 和 BRS 的关系尚未得到充分研究。我们假设，在 CHF 患者中，HRV 和 BRS 的变化与个体的容量/强度训练负荷（TL）呈剂量反应关系。
20 名在最佳药物治疗下稳定的梗死后 CHF 患者随机分为有氧运动持续训练（ACT）或有氧运动间歇训练（AIT）组，进行 12 周的训练。通过 Training Impulses（TRIMPi）方法监测个体 TL，该方法使用基线时跑步机测试中确定的个体 HR 和乳酸廓清来确定。在整个研究过程中，分别在休息时和 3 周后评估 HRV（平均 R-R 间隔的标准差）和 BRS。
HRV、BRS 和 R-R 间隔随训练而显著增加，与运动的剂量高度相关，具有二阶回归模型（r²范围为 0.75 至 0.96；P<0.001），在 ACT 组中呈钟形，在 AIT 组中呈渐近形曲线。这些变化伴随着功能能力的显著提高。在任何变量中，ACT 和 AIT 之间均未检测到显著差异。
这些结果表明，在 CHF 患者中，运动训练对 HRV 和 BRS 的改善与 TL 呈非线性剂量相关，在中等运动剂量下效果最佳。
