The majority of men and women in Great Britain do not take enough physical activity for a health benefit. A sedentary lifestyle is probably more common than any other classic cardiovascular risk factor - smoking, hypertension, raised blood cholesterol or obesity. Physically inactive people in Great Britain have about double the risk of heart attack and an increased risk of stroke compared with those who are moderately to vigorously active. These higher levels of activity are also associated with a 50% reduction in the likelihood of dying after a heart attack. Physical inactivity plays a critical role in the development of overweight/obesity and non-insulin dependent diabetes mellitus and there are important links with blood pressure, thrombogenesis and mobility and possibly lung function. After a heart attack a programme of physical activity in those who have been previously inactive reduces the chances of re-infarction. There is a strong case for promoting physical activity in men and women at all ages including the elderly, with reduction in all cause mortality at whatever age a more physically active lifestyle is adopted.

How much physical activity?

The perceived message for many years has been that physical activity must be vigorous and 'sporty', with a goal of 20-40 minutes activity on at least three days in the week. While this may be appropriate for those who are already active, it is unrealistic and discouraging for the majority who are currently inactive. There is now good evidence that regular and frequent aerobic physical activity at a moderate intensity is protective against heart attacks. It would be highly desirable if everyone could aim for an average of 30 minutes moderate activity on at least five days of the week, with reference to their doctor if any medical condition is present. Walking is the best exercise for ordinary people doing ordinary activities.

Moderate intensity activity makes you feel warm and slightly out of breath e.g brisk walking (about 4 mph), cycling, gardening, swimming and dancing. Sedentary people should start at a low level and very gradually increase their activity in duration, frequency and intensity.

Are there any risks?

The presence of ischaemic heart disease (angina, previous heart attack) is not a contra-indication. These patients should take physical activity within the limits of angina or breathlessness and avoid extremely cold weather and trying to walk through chest pain. There is some evidence that vigorous activity in hypertensive subjects may increase the risk of heart attack, particularly those with other risk factors present, but such subjects benefit considerably from moderate activity. Unaccustomed or erratic physical exertion, particularly if vigorous may be hazardous in middle-age and the sedentary should first move to low levels of activity and gradually increase as their fitness to do so improves.