Out of 893 people around 80 years old, researchers found that the most active seniors had a lower risk of dying over the four-year study compared to those who moved the least.

"It's another strong piece of evidence that all seniors should be participating in physical activities," said Dr. Catherine Sarkisian, director of the Los Angeles Community Academic Partnership for Research in Aging.

Sarkisian, who was not involved in the new study, told Reuters Health this does not prove exercise makes people live longer. It could be that people who were healthy enough to exercise are the ones who would have lived longer anyway.

However, she said there is enough evidence to suggest that people who are more physically active are less likely to lose their memory or have to go to a nursing home, for example.

To see whether activity levels make a difference in lifespan, researchers led by Dr. Aron Buchman, a professor at Rush University Medical Center in Chicago, measured the daily activity level of local seniors, most in their late 70s and 80s, over 10 days.

The participants wore a small device on their wrists to record how much they were moving throughout the day.

The researchers then followed the group for about four years, during which a quarter of the seniors -- 212 -- died.

The seniors who were most active had about a 25 percent lower chance of dying compared to those who were least active over the four years, according to results published in the Archives of Internal Medicine.

Buchman and his colleagues wrote that the link between physical activity and a lower risk of death remained even after taking into account traits that may have affected both seniors' exercise routine and chance of dying, including mental ability, chronic health conditions and symptoms of depression.

"This suggests if you're increasing your activity -- even in your home -- it has some advantages," said Buchman.

Sarkisian thinks there is a stereotype that seniors are too old to learn new habits, but she said past studies have shown the opposite.

"Physical activity is one of the most important things that seniors can do to improve their health for the rest of their lives," she added.

People are motivated to exercise for different reasons, said Sarkisian. Some may want to exercise after seeing a friend die, become ill or fall. Others may want to exercise because of the immediate physical benefits, such as improved mood.

Older adults can check their local senior centers for exercise programs or talk to their doctors or a physical therapist for ideas, Sarkisian said. There are also programs tailored for people with physical limitations, such as those who are wheelchair bound or at an increased risk for falling.

Buchman said it can also be as simple as an older person increasing their activities around the house.

"If you can do light activity, do light activities."

SOURCE: bit.ly/wc6FXL Archives of Internal Medicine, online March 12, 2012.

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