Health: Is 30 minutes a day enough?

30 November 2007

The government changed its emphasis on physical activity guidelines from vigorous activity to moderate in the 1990s. The ‘something is better than nothing’ method has been recently criticised by exercise physiologist Dr Gary O’Donovan for its ‘one-size-fits-all’ approach.

Gary O’Donovan, lecturer in sport and exercise medicine, University of Exeter.

‘It is important to stress that 30 minutes of moderate-intensity physical activity per day is associated with considerable health benefits, including a 30 to 50 percent reduction in the risk of diabetes, heart disease and mental illness. But clubs need to employ qualified and experienced health and fitness professionals to enable people of all ages to make the transition from couch potato to brisk walker, and, where appropriate, from brisk walker to formal exerciser.

The challenge facing scientists and the fitness industry is to better characterise ‘moderate-intensity’ in individuals of different functional capacities and different training histories. We must also describe the dose-response relationship between exercise and health without frightening off couch potatoes. Moderate activities are those that demand around 40 to 60 percent of one’s aerobic capacity, which is equivalent to 12-13 on Borg’s RPE scale. Many untrained middle-aged individuals will find brisk walking a moderate intensity activity. However, the same individuals will find brisk walking ‘light’ after a few weeks and will need to include other activities such as walking uphill, jogging, and, with time, running.

Health clubs will be rendered obsolete if the fitness industry does not promote the fact that, for most people, formal aerobic exercise offers greater health benefits than walking, gardening, stair-climbing and other ‘lifestyle’ activities.’

*Article taken from ‘Leisure Opportunities’ – Issue number 464.