Study: 15 minutes of exercise can help

LOS ANGELES -- Don't despair if you can't fit in the recommended 30 minutes of daily exercise. Growing evidence suggests that even half that much can help.

It's still no excuse to slack off. Regular exercise strengthens muscles, reduces the risk of some diseases and promotes mental well-being. The more exercise, the better.

But not everyone has the time or willpower. So researchers set out to find the minimum amount of activity needed to reap health benefits. The findings by a study in Taiwan suggest just 15 minutes of moderate exercise a day can lead to a longer life.

This "may convince many individuals that they are able to incorporate physical activity into their busy lives," Dr. Anil Nigam of the University of Montreal said. Nigam had no role in the research but wrote an editorial accompanying the Taiwan study published online yesterday in The Lancet.

Guidelines by the World Health Organization, the United States and other countries recommend a half-hour of moderate workout most days of the week for adults, such as brisk walking, bike riding and water aerobics.

Health groups have suggested breaking it down into smaller, more manageable chunks of time such as three 10-minute spurts a day on weekdays.

The latest study, led by researchers at the National Health Research Institutes in Taiwan, sought to determine whether exercising less than a half-hour was still helpful. About 416,000 adults were asked how much they exercised. They were then put into groups of varying activity levels and their progress was tracked for eight years on average and life expectancy projected.

Those who exercised just 15 minutes a day cut their risk of death by 14 percent and extended life expectancy by three years, compared with those who did no exercise. -- AP