You don't need to go for the burn to shed pounds. A walk to the bus stop is as good as an intense workout for women trying to lose weight, American researchers say.

The study by John Jakicic and colleagues from the University of Pittsburgh, published in the Journal of the American Medical Association, monitored 200 overweight but otherwise healthy women aged 21 to 45 who were put on a diet and assigned to different exercise regimes.

The women lost an average of 25lb (11kg) over six months and kept the weight off for the rest of the year, regardless of how much exercise they did. They were encouraged to exercise five days a week for 40 to 60 minutes and most chose walking as their favoured physical activity. There was no significant difference in the amount of weight lost or in the level of fitness gained between the moderate group who walked normally and the vigorous group who made themselves sweat.

Another study in the same issue of the journal suggests that exercise also has a protective effect against breast cancer.