However, leisure-time physical activity once or twice a week improves the chances of survival even more, says Kristina Sundquist, M.D., Ph.D., of the Karolinska Institutet in Stockholm.
For that reason, Sundquist says, "preventive resources among the elderly should provide more opportunities for physical activity."
The study appears in the American Journal of Preventive Medicine.
Sundquist and colleagues interviewed 3,206 people aged 65 and older, following them for 12 years or until they died.
Those who exercised occasionally reduced their chances of death before the study's end by 28 percent. Those who were physically active once a week reduced their early mortality risk by 40 percent, but exercising more frequently or more vigorously beyond that level did not improve their outcomes.
Physical activity probably keeps people alive longer because it reduces the likelihood of death from heart disease, Sundquist says.
Diabetes, hypertension and current smoking also increased risk of mortality. Obesity was not a risk factor in this group, she says.
To encourage moderate exercise among the elderly, Sundquist suggests that senior centers offer opportunities for walking or bicycling, and that doctors do more.
"Healthcare professionals should encourage elderly people to be physically active, even occasionally," she says.
The study was supported by grants from the National Institutes of Health, the Swedish Council for Working Life and Social Research, the Swedish Research Council, the Knut and Alice Wallenberg Foundation and the Stockholm County Council.
BY AARON LEVIN, SCIENCE WRITER
HEALTH BEHAVIOR NEWS SERVICE
FOR MORE INFORMATION:
Health Behavior News Service: (202) 387-2829 or www.hbns.org.
Interviews: Contact Kristina Sundquist, M.D., Ph.D., at Kristina.Sundquist@klinvet.ki.se.
American Journal of Preventive Medicine: Contact the editorial office at (858) 457-7292.
Journal
American Journal of Preventive Medicine