Exercise in general, and running in particular, helps to ward off disability in old age and may even extend life, according to a study that has taken more than 20 years to complete. The notion that exercise is good for you has been around for a long time, but the new study, carried out at Stanford University and published in this month's Archives of Internal Medicine, is one of the first to test its veracity over an extended period.

In 1984 Eliza Chakravarty and her colleagues surveyed 284 members of a nationwide running club as well as 156 healthy individuals recruited as controls from university faculty and staff. All the participants were older than 50 when the study began and all were required to complete an annual questionnaire giving details of exercise frequency, body mass index and disability.

After 19 years, 15 per cent of the runners had died compared with 34 per cent of the control group. The runners consistently showed lower levels of disability as they approached their 90s. The researchers say their findings support the idea that moderate to vigorous activity at all ages improves length and quality of life.

一项耗时20多年才完成的研究显示，总体而言运动，尤其是跑步，有助于防止老年能力丧失，甚至可能延长寿命。运动有益于身体的理念已经存在了很长时间，但斯坦福大学(Stanford University)进行的此项新研究，是最先在一段较长的时期内验证其真实性的研究之一。该研究发表在8月的《内科学文献》(Archives of Internal Medicine)上。

1984年，伊莱扎•切克拉瓦蒂(Eliza Chakravarty)和她的同事对一个全国性跑步俱乐部的284名成员以及作为对照从大学教职员工中招募来的156名健康个人进行了调查。所有参与者在研究开始时年龄都超过50岁，所有人每年都必须完成问卷调查，提供运动频率、身体质量指数(body mass index)和能力丧失的详细资料。

19年后，跑步者中有15%的人去世，对照组中则有34%的人去世。在接近90岁时，跑步者一直表现出较低的能力丧失程度。研究者表示，他们的发现支持了这样一种观点，即在任何年龄段，中等至激烈程度的运动都有助于延长寿命、提高生命质量。