Running to save your life

Press, 9 August 1985, Page 14

Running to save your life

DENIS DWYER, information officer, Canterbury Hospital Board, puts the case on running for health.

In Christchurch, and round much of the world in recent years, thousands of runners are taking to the streets and parks, and often going in fun runs, half marathons, and marathons. Studies of the effects of running on health are also under way now.

One important measure of health is blood pressure. The higher the blood pressure the more work the heart has to do. High blood pressure is a major cause of hardening or narrowing of the arteries.

There have been several studies of the effect of exercise — and jogging in particular — on blood pressure. Most studies indicate an increase in fitness is followed by a fall in blood pressure. A Californian study of 1977, for example, examined two groups — middle-aged male and female joggers who were averaging 64km of running a week, and considerably more sedentary age-matched community “control” subjects. But the runners did differ from control subjects in levels of obesity, and possibly other relevant factors.

An Australian study presented in 1984 showed that increased physical activity for one month lowered the blood pressure of all those in the group. Impressive evidence that weight loss in itself lowers blood pressure was given in an Israeli study of 1978. Of 81 hypertensives who went

on a four-month diet and lost an average of 9.5 kg, 79 had a significant fall in blood pressure.

The National Heart Foundation of New Zealand, commenting on exercise in general, says that vigorous physical activity, particularly during leisure, reduces the risk of fatal and nonfatal coronary heart disease events.

Also, that regular exercise increases high density lipoproteins which are thought to protect against coronary heart disease, and that those who exercise regularly are more likely to be non-smokers, leaner in build, and to have lower blood lipids and blood pressure.

The foundation sounds a note of caution that vigorous physical activity does not confer absolute protection against coronary heart disease. Sudden death and myocardial infarction has occurred, it says, in welltrained runners. But while there is the occasional runner who drops dead from a heart attack and is newsworthy, it says, there are hundreds of thousands who run regularly to improve their physical fitness and reduce the risks of a heart attack who don’t make the headlines. This was confirmed in a study of British civil ser-

vants. It showed that the risk of fatal heart attack in those undertaking vigorous sporting activities was 40 per cent that of the subjects not undertaking vigorous exercise.

Those not fit are advised to start their exercise programme at a suitably low level, and

build up gradually. The wisdom of this advice would appear to be confirmed by a study of the incidence of death during jogging in Rhode Island, from 1975 to 1982 which found that deaths per hours of jogging were highest in men aged 30 to 39 years, and decreased with increasing age.

Perhaps this reflects men in their 30s trying to do too much and too soon, whereas those who are older have adapted better to their capabilities. The effect of running on lower limbs has also been studied.

At a symposium held in Sydney in June this year, Dr Brian Corrigan and Dr Bain Shenstone of the Rheumatology Department of Concord Hospital, Sydney, presented a paper on hip and groin problems in runners. The current world-wide

involvement in running has brought with it, they say, an increase in overuse injuries of the lower limb. In their experience the hip and groin injuries account for up to 10 per cent of all such running injuries.

Rather strangely, they say, they appear to be more common in the more elite runner than in the jogger. At the same symposium, Dr Michael Mira and Dr Suzanne Abraham, of the University of Sydney, presented a paper on amenorrhoea in female runners. Amenorrhoea — the absence or abnormal stoppage of the monthly flow of blood — occurs most commonly, they found, amongst runners and ballet dancers, and less frequently amongst swimmers.

It occurs in a small proportion of the women undertaking endurance training. Women runners more likely to develop amenorrhoea are those with low body weight, and a low proportion of body fat, or those who have a marked decrease in body weight at the onset of training.

The prevalence of exercise induced amenorrhoea increases with increased

training distance, and is most common in those who run more than 80km a week. Amenorrhoea is not a reliable method of birth control. Whether athletic amenorrhoea should be treated is unclear they say, and whether continued athletic amenorrhoea over many years results in osteoporosis is not known.

Their study also found that in younger women the age of menarche may be delayed. On the other hand, they said, the benefits of aerobic training for women are many: an increase in bone density with possible protection against osteoporosis in the postmenopausal years, a possible reduction in cardiovascular disease, lessening of menstrual flow, release of hostility and anxiety, and an increased feeling of physical and mental well being. Dr Shailer Weston, senior casualty officer of the Canterbury Hospital Board, is himself a keen runner, and has run many half marathons.

He advises beginning runners to have a medical check-up especially if they are over 35, to build their programme up gradually, to always warm up beforehand, to have appropriate footwear and well-fitting clothes to avoid chafing, and not to become obsessive and let running dominate their lives.

His predecessor as senior casualty officer, Dr Duncan Scott, aged 67, has been a runner for the last 20 years. When he started, he says, joggers were regarded as at best eccentrics even though they ran only a mile or so. In recent years he has been

running between 50 and 60 km a week.

Most people are capable of running, he says, but it is not some people’s thing. Runners should go at the rate that suits them and find by perseverance what they can do. To get benefits a certain amount of dedication is needed.

The professor of medicine in the Christchurch Clinical School of Medicine, Don Beaven, is in favour of gentle jogging if it is enjoyable, but believes walking would probably be of benefit to more people. So each person must find what form of exercise is most appropriate. Activities, says the National Heart Foundation, which make you sweat or puff and pant for 20 minutes or more at a time — including running, cycling, swimming and long steady walks — will help to make you fit. Golf, bowls, and active gardening are all worth while, but may not achieve quite the same training effect.

A fit person enjoys life better, can cope better with stresses and strains, is less likely to pull or damage muscles or tendons with strenuous physical activity, has fewer heart attacks than others, and has a better chance of recovery. “But perhaps the effect of regular running on general health is of less importance than its undoubted effect on mood,” says Dr Weston.

“Most runners will say that not only are they fitter but they are more cheerful, optimistic and generally happier and some doctors consider it is a good treatment for mild depression. Certainly the cares of the world seem to diminish when the track suit is donned, the running shoes put on and the pavements pounded — if you don’t believe this why not try it?"