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A research study published in the July 12, 2006, issue of the Journal of the American Medical Association (JAMA) shows that daily activity can have a positive impact on life expectancy in older adults. It was previously known that exercise had a positive effect on life expectancy. This study also shows that those who are active in their daily routine, even in non-exercise activities, are also getting positive benefits.

This study, conducted by Todd M. Manini, Ph.D., and his colleagues at the National Institute on Aging in Bethesda, Md., was designed to determine the association of what the researchers called “free-living activity energy expenditure” and death rates. The study looked at a group of 302 high-functioning, community-dwelling seniors ranging in age from 70 to 82.

In this study, the researchers measured energy expenditure over a two-week period using sophisticated processes of tracking certain isotopes of hydrogen and oxygen as eliminated from the body as carbon dioxide. This process determined the amount of energy expenditure and, therefore, the activity of the individual. The 302 participants were followed on average for just over six years. Over this period, 55 participants (18.2 percent) died. The researchers then compared the activity levels of all participants to see if there was a correlation between death rates and activity levels.

The results showed that, after adjusting for other factors, higher levels of activity energy expenditure and physical activity were indeed associated with a lower risk of death. When the researchers categorized activity levels of the participants into three groups, they found that the risk of death was only 12.1 percent in the group with the highest level of activity energy expenditure. The group in the middle third, relative to activity level, had a 17.6 percent risk of death. However, the group in the bottom third level of activity had a 24.7 percent risk of death. Statistically, this meant that those with the highest level of activity had a 69 percent better chance of survival than those with the lowest activity.

The authors of this study commented, “Our study suggests that any activity energy expenditure in older adults can help lower mortality risks.” They continued, “Efforts to increase or maintain free-living activity energy expenditure will likely improve the health of older adults.” In the study, they concluded, “Objectively measured free-living activity energy expenditure was strongly associated with lower risk of mortality in healthy older adults. Simply expending energy through any activity may influence survival in older adults.”