True or false? It is necessary to engage in vigorous, continuous exercise to reap health benefits... Many would agree with this statement, but research on physical activity shows that even moderate activity, done in short bouts of 8 to 10 minutes, yields substantial health benefits.

A recent article in the prestigious Journal of the American Medical Association seeks to dispel this common misconception. The authors, whose names read like a who's who of physical activity research, make the following recommendation: "Every adult should accumulate 30 minutes or more of moderate-intensity physical activity on most, preferably all, days of the week."

Whereas earlier recommendations called for three 20-minute sessions of vigorous physical activity every week, this recommendation emphasizes the benefits of moderate activity. Moderate activity is the equivalent of 30 minutes of brisk walking every day. At a brisk pace, an average adult can walk between 2.5 to 3 kilometres in a half hour. That's about twice as fast as a leisurely stroll.

The new recommendation also reflects recent research showing how the total energy expenditure is more important than the actual length of the workouts. Therefore, it is possible to do a few short sessions of 8 to 10 minutes to reap the same health benefits as a continuous 30-minute workout.

This has significant implications. For example, it means that since physical activity can be accumulated in several short periods, it is a lot easier to fit into a busy schedule. Simple activities such as the following add to the total energy expenditure:

• walking instead of driving short distances (a definite plus for the environment)
• doing calisthenics or pedaling a stationary cycle while watching television
• walking or running 10-15 minutes during lunch hour
• taking the stairs instead of the elevator
• gardening, doing housework, raking leaves, mowing the lawn (without a tractor!)
• playing with the children.

As long as these activities are done at an intensity comparable to that of brisk walking, adequate health benefits will accrue. People who prefer leisurely strolls to brisk walking need not worry, however. The secret then is to do the activity more often, for longer periods, or both.

In the same vein of thought, individuals who don't engage in any physical activity can begin with a few minutes every day, gradually building up to 30 minutes a day. Those who are active some of the time can strive to adopt a more frequent pattern of physical activity.

With a little effort every day, it is possible to combine the comfort of a sedentary lifestyle, where everything is at our fingertips, with the benefits of an active lifestyle, where a world of health is at our toetips.