Stein P K, Ehsani A A, Domitrovich P P, Kleiger R E, Rottman J N
Division of Cardiology, Washington University School of Medicine, St Louis, MO, USA.
Am Heart J. 1999 Sep;138(3 Pt 1):567-76. doi: 10.1016/s0002-8703(99)70162-6.
To determine the effect of exercise training on cardiac autonomic modulation in normal older adults by using analysis of heart rate variability.
The exercise group consisted of 7 men and 9 women aged 66 +/- 4 years. The comparison group consisted of 7 men and 9 women also aged 66 +/- 4 years.
Heart rate variability was determined from 24-hour Holter recordings before and after 12 months of supervised exercise, which consisted of 3 months of stretching and 9 months of 5 hours/week aerobic exercise at approximately 70% of maximal oxygen uptake. Heart rate variability was measured at baseline and 12 months later in the comparison group, who had not changed their usual activity level.
In the exercise group maximal oxygen consumption increased from 1.8 +/- 0.5 L/min to 2.2 +/- 0.7 L/min (P <.05). The standard deviation of normal interbeat intervals increased from 126 +/- 21 ms to 142 +/- 25 ms. Mean nighttime heart rate decreased from 67 +/- 6 beats/min to 63 +/- 5 beats/min. Increased fitness level had little effect on indexes of heart rate variability, which reflect parasympathetic or mixed sympathetic/parasympathetic modulation of heart rate. There was no change in heart rate or heart rate variability in the comparison group.
Exercise training increases total heart rate variability in normal older adults. The most marked alterations are in nocturnal heart rate. Heart rate variability is stable over a 1-year period in older adults who do not alter their activity level.
通过心率变异性分析，确定运动训练对正常老年人心脏自主神经调节的影响。
运动组由7名男性和9名女性组成，年龄为66±4岁。对照组由7名男性和9名女性组成，年龄也为66±4岁。
在12个月的监督运动前后，通过24小时动态心电图记录来测定心率变异性。该运动包括3个月的伸展运动和9个月每周5小时、约为最大摄氧量70%的有氧运动。对照组未改变其日常活动水平，在基线和12个月后测量心率变异性。
运动组的最大摄氧量从1.8±0.5升/分钟增加到2.2±0.7升/分钟（P<.05）。正常心动周期间期的标准差从126±21毫秒增加到142±25毫秒。夜间平均心率从67±6次/分钟降至63±5次/分钟。体能水平的提高对反映心率副交感神经或交感神经/副交感神经混合调节的心率变异性指标影响不大。对照组的心率和心率变异性没有变化。
运动训练可增加正常老年人的总心率变异性。最显著的变化是夜间心率。在未改变活动水平的老年人中，心率变异性在1年期间保持稳定。
