Role of structured physical activity in preventing or delaying mobility disabilities in older adults

www.wfubmc.eduMar 19 2010

Wake Forest University Baptist Medical Center, together with Wake Forest University, will play a key role in a new study that seeks to determine whether a program of structured physical activity can prevent or delay major mobility disabilities in older adults.

The six-year study, called the Lifestyle Interventions and Independence for Elders, or LIFE, will be the largest study to date that looks at ways to prevent mobility disability in seniors. When completed, funding for the project is expected to total more than $60 million from the National Institute on Aging (NIA), including $29.5 million in federal stimulus funds from the American Recovery and Reinvestment Act of 2009.

"This study represents an important milestone in aging research," said Stephen B. Kritchevsky, Ph.D., director of the Medical Center's J. Paul Sticht Center on Aging. "In many ways the LIFE study is the capstone of 20 years of our program's exercise-related research."

Many studies have shown that regular exercise improves physical performance. The U.S. Department of Health and Human Services recommends that adults engage in at least 150 minutes of moderate-intensity or 75 minutes of vigorous-intensity aerobic activity each week, as well as muscle-strengthening activities.

Still, little is known about whether exercise can actually help prevent major mobility disability, defined as the inability to walk a quarter of a mile, or four blocks.

For older adults, staving off disability could help them maintain their physical independence and enhance the quality of their later years.

"Older adults value their independence as much as any aspect of their lives and mobility is absolutely central to the preservation of independence," said Tony Marsh, Ph.D., associate professor in Health and Exercise Sciences at Wake Forest University. "This study is important because it will determine whether the loss of mobility, we typically observe in older adults, can be prevented."

The randomized controlled trial will follow 1,600 sedentary adults ages 70 to 89 and at risk of mobility disability at eight institutions around the country.

Primarily, the study seeks to gauge whether there are long-term effects of physical activity interventions on major mobility disability. Investigators will also examine the effects of physical activity on a number of factors, including cognitive function, serious fall injuries, disability in basic activities of daily living, cardiovascular events, hospitalization and nursing home admission. They will also examine quality-of-life measures such as depression symptoms, sleep quality, stress and satisfaction with life.

In addition, the project will assess the cost effectiveness of walking programs for the elderly, and whether the money spent on such programs can help reduce medical expenses for injuries and illness that might otherwise result from lack of adequate physical activity.

"As people age, it is particularly critical that they take an active, personal role in their health care," said W. Jack Rejeski, Ph.D., Thurman D. Kitchin Professor of health and exercise science at Wake Forest. "The LIFE study is the largest effort to date to promote this philosophy and to teach people how they can improve the quality of their lives. Wake Forest is excited to play a major role in the study and to provide this opportunity for older adults in the Triad region."

The Medical Center, with researchers from the Sticht Center and the Department of Health and Exercise Sciences at Wake Forest University, will have a study field site headed by Kritchevsky and Marsh. The Medical Center's Department of Biostatistical Sciences will serve as the study's overall data management and analysis center. The University of Florida (UF) will serve as the overall coordinating center. The Wake Forest team and UF will join Northwestern University, Pennington Biomedical Research Center (a campus of the Louisiana State University system), Stanford University, Tufts University, the University of Pittsburgh and Yale University as study field sites.

Enrollment of 200 local study participants begins this month. Eligible participants will be randomly assigned either to take part in a moderate-intensity physical activity or a health education program on successful aging. Individuals will be followed for up to three-and-a-half years.