Written by Dr Ben Ewald and published in the Newcastle Herald.

Dr Ewald is a senior lecturer in epidemiology in the faculty of medicine and public health.

As a doctor I like to keep an eye on the latest medical research, and the thing that has impressed me the most over the last few years is the importance of physical activity in keeping people healthy.

While diet, blood pressure and not smoking are important, getting sufficient exercise is even more important to overall health than these other factors.

While the benefits of being active and fit have been known for a long time, the research done before the last five years was hampered by the difficulties of measuring total physical activity, or of measuring fitness.

While weight can be measured with only  1per cent error, physical activity has generally been measured with techniques with about 30per cent error so the research tended to underestimate its effect.

This was all changed by the release of results from the Aerobics Centre’s Longitudinal Study in which a large group of Americans had their fitness measured and were followed for  12 years.

In that group, being fit gave a 65per cent reduction in the risk of dying of any cause.

Compared to other health factors that is a huge effect.

Exercise has benefits across many health areas: it prevents osteoporosis, depression, uterine fibroids, cancers of the breast, bowel and prostate, diabetes, and heart disease.

It is an effective treatment, among other things, for osteoarthritis, back pain, chronic fatigue, emphysema, and heart failure.

These benefits are available at any age, so even the  elderly can benefit from daily physical activity.

If exercise was a pill, we would give it to everyone, and you can be sure that the pharmaceutical industry is hard at work to develop a pill that mimics the benefits.

The reason that this matters is that most people in Australia do not do enough physical activity.

In the National Health Survey only 41per cent report doing the recommended 30 minutes of activity on at least five days a  week.

Research done with movement recorders, however, has shown that people drastically over-report in surveys and the proportion actually achieving this dose of exercise is likely to be less than 10per cent.

With exercise being so important, but so many people missing out on its benefits, the total effect on the health of Australians is enormous.

It’s worth examining some of the reasons I hear for not doing more physical activity.

“I don’t like running”: Getting hot and sweaty is not necessary; moderate exercise such as walking has many health benefits.

“I tried exercising but I didn’t lose any weight so I stopped’’: There is a health benefit from exercise even without weight loss. If you are overweight it is much better to be fit than unfit. Put the other way around, you can starve yourself thin but you can’t starve yourself healthy.

“I’m too busy’’: People who work long hours then have family responsibilities may have trouble finding the time for “exercise” so have to be creative about building physical activity into their work and home routine.

Active transport (walking, cycling) to work or shopping is an excellent option for the time poor. It gets the job done and a bit of physical activity is a beneficial side effect.

“I can’t do it since my knees wore out’’: Exercise is a good treatment for knee pain but may need supervision by an exercise physiologist. Ask your doctor.

In recognition of the many practical and motivational barriers people face in undertaking enough physical activity, my colleagues and I at the University of Newcastle are running a trial of coaching by exercise physiologists to help sedentary people become more active. The NewCoach trial is open to people aged 18 to 100, recruitment is via participating general practitioners and will continue throughout 2013.

If you’re looking for a way to get started, here are some things you could do:

● Walk or cycle to work. If it’s too far, walk the last kilometre. Instead of meeting for coffee, meet for a walk.

● When taking kids to sport don’t just stand there, run around the perimeter.

● Have a back-up plan for bad weather. If it’s too hot or too wet for outdoor activity have an indoor alternative.

● Buy a pedometer and aim for 8000 steps every day.

● If you have a chronic health condition, join a HeartMoves class. Watch the video clip ‘23 and a half hours’ by Dr Mike Evans.