What types of activities and activity levels are appropriate for general health and wellbeing?

This answer is brought to you by many of the Australian nutrition professionals who regularly contribute to a nutrition email discussion group.

For most of the time that humans have been on Earth there has been no need for anyone to be advised to 'be physically active'. Our forebears, who were 'hunters and gatherers', did not have the luxury of being able to choose to be active or sedentary - not if they wanted to eat, anyway! After hundreds of thousands of years of required activity, most people (at least in Western countries) are now free to be inactive if they so wish. The advent of aeroplanes, trains, cars, electric windows, remote controls, computer work stations and so on has meant that the vast majority of Australians can now choose to be largely sedentary and still live (or at least exist!)

A few people still do have active occupations (eg, labourers, infantry soldiers, professional sportspeople); for such people there is still no choice but to be physically active. For the remainder (the vast majority of the population) physical activity is an 'optional extra' that requires a conscious choice to be made. 

The motivations to be active can vary: some people choose to be active for general health; for others the motivation may be physical fitness, weight control, social contact or simply sheer enjoyment. In this FAQ the currently-recommended levels of activity for general health are discussed. Other FAQs in this series discuss activity in relation to weight control and in relation to physical fitness.

How much exercise is necessary for general good health? Certainly, very high levels of exercise are associated with low levels of blood cholesterol, body weight, blood pressure and so on, even when the diet is extremely high in fat. For example, people who trek across Antarctica while pulling sleds weighing about 200 kg invariably finish their expeditions weighing less and with improved blood cholesterol/blood pressure. This occurs despite eating a diet that provides over 50% of its energy from fat, and much of that as saturated fat.

Many people believe that you have to exercise like Antarctic expeditioners or run marathons to derive a benefit from exercise. This is not correct. The results of many studies in the West strongly support the belief that moderate physical activity is protective against a wide range of diseases - especially diabetes, stroke, colon cancer, and breast cancer. It is also likely that moderate physical activity has some positive benefit on the risks of stroke and osteoporosis (chalkiness of the bones) and it is believed to foster social and mental well-being. For example, exercise has been used successfully as an adjunct in the treatment of mild, chronic depression.

The Active Australia Campaign recommends that for general health, 'You only have to exercise regularly, not seriously'. That is, the exercise doesn't have to be very high level and it doesn't have to be taken in 'one hit'. Rather, if you find it more convenient, you might prefer to take part in several short (eg, ~10 minute) periods of activity through the day, adding up to ~30 minutes of accumulated moderately-vigorous activity. If, however, you want to 'get it over and done with', it is suggested that you do one bout of ~30 minutes of moderately-vigorous activity on most days.

This raises the question 'what constitutes "moderately-vigorous activity"?'. Perhaps the most appropriate answer is 'any activity that causes you to start breathing a little harder than normal and causes your heart to start beating noticeably faster than usual'. If your breathing rate is elevated to the extent that you can still talk normally (just), but you cannot sing, you are exercising at about the right level of intensity. The activity of choice will depend on the availability of facilities, personal preferences, age and capabilities. Examples of suitable activities that you can do on your own include:

Walking: Good for nearly everyone because it is 'weight bearing' and hence likely to be protective against osteoporosis in the legs, hips and (to some extent) in the spine.

Swimming: Good for people who are carrying a lot of extra body fat (and for everyone else who can swim), but water activities do require access to a pool or to the sea.

Bike riding: Something that can be conducted either outside in the fresh air, or in the privacy of your home (on a stationary bike).

Non-competitive activities that are conducted in an organised, structured manner may be good for people who struggle to find the time (or self-motivation) to be active. Classes in aqua-aerobics for the unfit, the elderly or beginners; martial arts; jazzercise; aerobics; circuit training and so on are widely available. Similarly, dance classes are becoming very popular and cater for people of all ages. Organised activities such as these have social benefits, too.

Other suitable forms of exercise (depending on your age and skill level) include the traditional organised sports such as tennis, golf, netball, basketball, indoor cricket, softball and so on. There are now many organised social competitions in these and similar sports that cater for people over a wide range of ages and skill levels.

In addition to ~30 minutes of moderately-vigorous activity on most days, it would also be appropriate to include in your activity program some resistance activity and flexibility training (eg, stretching) for promotion of general health. Resistance training assists with maintaining strength and muscular endurance. This is especially important for older people because our muscles lose strength with ageing. Resistance exercise is the only form of activity that will slow down the rate of loss of strength. Callisthenics (eg, pushups, situps, chinups, flexed arm hang) and weight training are appropriate forms of resistance training.

Unless you are aware of the dangers involved in doing callisthenics or weight training inappropriately, and are confident that you can avoid those dangers, it may be a good idea to get professional advice from a personal trainer or at your local gym on how you can safely and effectively include resistance training in your lifestyle. A suitable weekly schedule might be (for example) four days of brisk walking, swimming or bike riding for a total of 30 minutes per day, 10 minutes of callisthenics on one day and 20 minutes of light weight-training on another.

Long, slow stretches are suggested as being the most appropriate form of flexibility training that you can do alone. Yoga is another popular form of activity that promotes psychological health at the same time as enhancing flexibility. Similarly, Tai chi (which also combines some of the benefits of exercise and meditation in the one activity) can help with flexibility and relaxation.

Above all, the recommendation is to make exercise a part of your day. In addition to your daily 30 minutes of accumulated activity and/or resistance training, to assist with energy expenditure and to promote general health you can:

• Use stairs in preference to escalators or elevators (lifts);
• Walk short distances (eg, to the corner shop for the Saturday newspaper or a litre of milk) rather than drive;
• If it is safe (ie, if bike paths exist to keep you away from cars and other heavy traffic) ride a bike to work;
• Take the dog for a walk in the park or simply make a habit of going for a walk after dinner (in summer) or before dinner (winter) each fine evening;
• Use non-power gardening tools such as hedge clippers and edge trimmers;
• Turn some of the backyard into a vegetable garden using shovel, fork, rake and wheelbarrow;
• If you burn firewood, have it delivered unsplit and then split it yourself with an axe.

The World Health Organisation has recently proposed the adoption of the following definition: 'Health is a dynamic state of complete physical, mental, spiritual and social well-being and not merely the absence of disease or infirmity'. Daily moderate physical activity can assist with improving all these aspects of overall health.

For more information Nutrition Australia recommends:

• Eating Activity, Sport and You

Back to Frequently Asked Questions Index

[Date issued: August 1999]

Disclaimer: This material is provided on the basis that it constitutes advice of a general nature only. It is not intended to replace the advice of a physician or a dietitian.