Exercise for every body

Just how much do we need to do to stay in shape? And what type of exercise is best?

According to the Central Health Education Unit of Hong Kong's Health Department, the specific type and amount of activity required to prevent weight gain have not yet been established by studies. It differs between individuals, but in general more activity increases the probability of successful weight maintenance or loss.

The Health Department offers the following weight loss tips.

For weight maintenance

International guidelines recommend that adults do 45 to 60 minutes of moderate-intensity physical activity each day, while controlling energy intake to prevent becoming overweight or obese.

A review of randomised, controlled trials in early-post-menopausal women, published in 2004 in the journal Sports Medicine, suggested that walking at least 30 minutes per day plus twice-weekly resistance exercise sessions was likely to be effective in preserving normal body weight.

If you've been sedentary, build up progressively to your goal, starting with 10 to 20 minutes every other day during the first week or two, to minimise potential muscle soreness and fatigue.

For weight loss

Overweight or obese adults are encouraged to do at least 30 minutes of moderate-intensity physical activity five or more days a week. It can be done in one session or over a few sessions lasting 10 minutes or more. Loss of 450 grams of body fat requires, in general, about 3,500 calories of energy expenditure.

Even if no weight is shed, the overweight are encouraged to increase physical activity, as it brings other health benefits, such as reduced risk of type 2 diabetes and cardiovascular disease.

Walking is excellent for overweight people - brisk walking counts as moderate-intensity physical activity for both the sedentary and overweight. Weight-bearing physical activity may be difficult for some people with a body mass index over 35, particularly those with joint problems. Try non-weight-bearing moderate-intensity physical activities, such as cycling, swimming and water aerobics.

Including muscle strengthening exercises is also suggested for a balanced exercise programme.

For maintaining weight loss

Several studies have been conducted on the role of physical activity in preventing weight regain after an initial sizeable weight loss. Although these had different designs and methodologies, all the studies focused on people who had lost 13.6 to 22.7kg and had not regained the weight after several years. The studies using self-reported physical activity and energy expenditure generally support the notion that 60 to 90 minutes of moderate-intensity physical activity each day might be necessary for weight maintenance after such large weight loss.