Kasch F W, Wallace J P
Med Sci Sports. 1976 Spring;8(1):5-8.
The reported decline in Physical Working Capacity (PWC) max is from 9-15 percent during the ages of 45 to 55 years. The use of vigorous physical activity to prevent this decline and to possibly protect against fatal myocardial infarction has been suggested. The purpose of this study was to investigate the effect of an endurance type exercise program on the maximal PWC of middle-aged men during a 10 year span. Sixteen men, initially 32-56 years (M-44.6), were trained with running or swimming at an intensity above 60 percent of VO2 max during a 10 year period. The average weekly running distance was 15 miles (25 km). The criterion for PWC was directly measured VO2 using the Douglas Bag/Scholander technique. No changes were observed in body weight, resting heart rate (HR), or resting blood pressure (BP). Maximal HR declined 7 beats per minute in 10 years. Pulmonary ventilation (STPD) increased approximately 18 percent. Mean VO2 max was essentially unchanged, 3.376 and 3.303 1/min STPD. VO2 max related to body weight was 43.7 initially and 44.4 ml/min-kg after 10 years. It was concluded that the usual 9-15 percent decline in PWC or VO2 max from age 45 to 55 years can be forestalled by regular endurance exercise. The results may have implications for protecting against heart attacks.
据报道，45至55岁期间，最大身体工作能力（PWC）会下降9%至15%。有人建议通过剧烈体育活动来预防这种下降，并可能预防致命性心肌梗死。本研究的目的是调查一项耐力型运动计划在10年期间对中年男性最大PWC的影响。16名男性，初始年龄为32至56岁（平均44.6岁），在10年期间进行跑步或游泳训练，强度高于最大摄氧量（VO2 max）的60%。平均每周跑步距离为15英里（25公里）。PWC的标准是使用道格拉斯袋/斯科兰德技术直接测量VO2。体重、静息心率（HR）或静息血压（BP）均未观察到变化。10年内最大心率每分钟下降7次。肺通气量（标准温度和压力干燥空气）增加了约18%。平均最大摄氧量基本未变，分别为3.376和3.303升/分钟（标准温度和压力干燥空气）。与体重相关的最大摄氧量最初为43.7，10年后为44.4毫升/分钟·千克。研究得出结论，45至55岁期间PWC或最大摄氧量通常9%至15%的下降可以通过定期耐力运动来预防。这些结果可能对预防心脏病发作有启示意义。
