Washington: Scientists have found that a particular gene in some elderly people may prevent them from fully reaping the health benefits of exercise.
Exercise has repeatedly been shown to reduce or slow age-related declines in physical function and is widely recommended for seniors, but the way that older people respond to exercise varies widely, researchers said.
A new study by Thomas W Buford from Department of Aging and Geriatric Research, University of Florida, studied whether the ACE I/D gene and its variations - the ID, DD, and II genotypes - impact some seniors' ability to fully reap the benefits of exercise.
Researchers followed 424 sedentary, mobility-limited seniors aged 70-89 for a year. Participants were randomly placed in a group that focused on either health education or physical activity.
The health education group received ongoing presentations on eating right, how to properly use medication, and other information on maintaining a healthy lifestyle, but did not perform exercise as part of the study.
Seniors in the physical activity group were taught a variety of strength (eg, squats and leg raises) and balance exercises and a walking programme that they were encouraged to perform both in a group setting and at home.
The researchers measured changes in walking speed and participants' ability to perform other tasks such as getting up from a chair.
They found that the physical activity intervention led to greater improvements walking speed among ID and DD genotype carriers (29.9 per cent and 13.7 per cent respectively).
However, among II genotype carriers, health education alone led to more improvements in walking speed than physical activity intervention (20 per cent vs 18.5 per cent).
In the physical activity group, II carriers also experienced smaller gains in lower body performance than those in the health education group.
These findings suggest that the ACE I/D genotype may be a significant factor in how well seniors respond to exercise, researchers said.
The study is published in the journal Physiological Genomics.