Exercise: How much is enough?

Quite possibly more than you think, according to a recent study published in the journal Archives of Internal Medicine.

In addition to limiting calories, overweight and obese women may need to exercise as much as 55 minutes a day for five days per week to sustain a weight loss of 10 per cent over two years, the report says.

This is at the high end of the Health Canada physical activity guide which calls for 30 to 60 minutes of moderate physical activity per day most days of the week.

While most health experts agree that 30 minutes of moderate exercise five times a week reduces the risk for cardiovascular disease and other illnesses, when it comes to keeping off unwanted pounds, recommendations are often confusing and contradictory. Recently revised U.S. guidelines, for example, suggest that previously overweight people may need 60 to 90 minutes of daily exercise to keep the pounds off.

An hour a day keeps weight gain away

"We did the study because of the whole confusion about this issue," study leader John Jakicic of the University of Pittsburgh told CanWest. "Once you lose it, how do you keep that weight off long-term?"

The study followed 201 overweight and obese women to calculate the amount of exercise needed to sustain a weight loss of 10 per cent or more of initial body weight over two years. The women ranged in age from 21 to 45 years and had body mass index readings between 27 to 40.

Study participants were told to eat between 1,200 and 1,500 calories a day and were assigned to four groups, each with a different activity level. They also received advice on modifying their eating and exercise habits as well as telephone support from the research team over the two-year period.