Ades P A, Waldmann M L, Meyer W L, Brown K A, Poehlman E T, Pendlebury W W, Leslie K O, Gray P R, Lew R R, LeWinter M M
Division of Cardiology, University of Vermont College of Medicine, Burlington, USA.
Circulation. 1996 Aug 1;94(3):323-30. doi: 10.1161/01.cir.94.3.323.
Older coronary patients suffer from a low functional capacity and high rates of disability. Supervised exercise programs improve aerobic capacity in middle-aged coronary patients by improving both cardiac output and peripheral extraction of oxygen. Physiological adaptations to aerobic conditioning, however, have not been well studied in older coronary patients.
The effect of a 3-month and a 1-year program of intense aerobic exercise was studied in 60 older coronary patients (mean age, 68 +/- 5 years) beginning 8 +/- 5 weeks after myocardial infarction or coronary bypass surgery. Outcome measures included peak aerobic capacity, cardiac output, arterio-venous oxygen difference, hyperemic calf blood flow, and skeletal muscle fiber morphometry, oxidative enzyme activity, and capillarity. Training results were compared with a sedentary, age- and diagnosis-matched control group (n = 10). Peak aerobic capacity increased in the intervention group at 3 months and at 1 year by 16% and 20%, respectively (both P < .01). Peak exercise cardiac output, hyperemic calf blood flow, and vascular conductance were unaffected by the conditioning protocol. At 3 and 12 months, arteriovenous oxygen difference at peak exercise was increased in the exercise group but not in control subjects. Histochemical analysis of skeletal muscle documented a 34% increase in capillary density and a 23% increase in succinate dehydrogenase activity after 3 months of conditioning (both P < .02). At 12 months, individual fiber area increased by 29% compared with baseline (P < .01).
Older coronary patients successfully improve peak aerobic capacity after 3 and 12 months of supervised aerobic conditioning compared with control subjects. The mechanism of the increase in peak aerobic capacity is associated almost exclusively with peripheral skeletal muscle adaptations, with no discernible improvements in cardiac output or calf blood flow.
老年冠心病患者功能能力低下且残疾率高。有监督的运动计划通过改善心输出量和外周氧摄取来提高中年冠心病患者的有氧能力。然而，老年冠心病患者对有氧训练的生理适应性尚未得到充分研究。
对60例老年冠心病患者（平均年龄68±5岁）在心肌梗死或冠状动脉搭桥手术后8±5周开始进行为期3个月和1年的高强度有氧运动计划的效果进行了研究。观察指标包括峰值有氧能力、心输出量、动静脉氧差、充血小腿血流量以及骨骼肌纤维形态、氧化酶活性和毛细血管密度。将训练结果与久坐不动、年龄和诊断匹配的对照组（n = 10）进行比较。干预组在3个月和1年时峰值有氧能力分别增加了16%和20%（均P <.01）。峰值运动心输出量、充血小腿血流量和血管传导率不受训练方案的影响。在3个月和12个月时，运动组运动峰值时的动静脉氧差增加，而对照组未增加。骨骼肌的组织化学分析显示，经过3个月的训练后，毛细血管密度增加了34%，琥珀酸脱氢酶活性增加了23%（均P <.02）。在12个月时，与基线相比，单个纤维面积增加了29%（P <.01）。
与对照组相比，老年冠心病患者在接受3个月和12个月的有监督有氧训练后，峰值有氧能力成功提高。峰值有氧能力增加的机制几乎完全与外周骨骼肌适应有关，心输出量或小腿血流量没有明显改善。
