Elderly joggers remained fit and active for longer than non-runners and were half as likely to die prematurely, scientists found.

They were also less likely to succumb to a range of age-related illnesses, including heart disease, cancer and neurological disorders.

The study, which spanned more than 20 years, began in 1984 when many experts feared the emerging craze for jogging might cripple pensioners with arthritis and orthopaedic injuries.

The U.S. research, published in the journal Archives of Internal Medicine, showed the opposite happening.

Professor James Fries, from the University of California at Stanford, said: 'The study has a very pro-exercise message. If you had to pick one thing to make people healthier as they age, it would be aerobic exercise.'

The study compared the progress of 284 members of a nationwide running club and 156 healthy but non-running individuals.

All were 50 or older at the start of the study.

Over the years, they filled in annual questionnaires asking about their ability to perform everyday activities such as walking, dressing, getting out of chairs, and gripping objects.

After 19 years, 34 per cent of the non-runners had died compared with 15 per cent of the runners.

Although both groups were more disabled by the end of the study, the runners remained in good health for longer.

Professor Fries said: 'Runners' initial disability was 16 years later than non-runners.  By and large, the runners have stayed healthy.'

Running not only appeared to slow the rate of heart and artery related deaths, but was also associated with fewer early deaths from cancer, neurological disease, infections and other causes.

There was also no evidence that runners were more likely to suffer osteoarthritis, contrary to the predictions of the 1980s.

'Running straight ahead without pain is non-harmful,' said the professor, who as well as being a runner is a mountaineer and an 'out-door adventurer'.

The researchers, whose findings appear in the journal Archives of Internal Medicine, believe regular exercise can reduce disability and death by improving the health of heart and arteries, strengthening bones, and reducing inflammation.

Running may also increase aerobic capacity - the ability to generate energy using oxygen - boost the immune system and improve thinking, learning and memory functions, they said.

They wrote: 'Our findings of decreased disability in addition to prolonged survival among middle-aged and older adults participating in routine physical activities further support recommendations to encourage moderate to vigorous physical activity at all ages.

'Increasing healthy lifestyle behaviours may not only improve length and quality of life but also hopefully lead to reduced health care expenditures associated with disability and chronic diseases.'

(Source: DailyMail)