PITTSBURGH – A 20-minute brisk walk around the neighborhood each day could significantly help older adults maintain their ability to walk, according to the results of the longest-running randomized clinical trial evaluating physical activity in the elderly.
The University of Pittsburgh was one of eight field centers that recruited and monitored trial participants. The much-anticipated findings will be presented today at the annual meeting of the American College of Sports Medicine in Orlando and concurrently published in the Journal of the American Medical Association. This study was funded by the National Institutes of Health (NIH).
“Doctors have long suspected that maintaining or starting physical activity is important in promoting good health as we age,” said Anne Newman, M.D., M.P.H., principal investigator on the study and chair of Pitt Graduate School of Public Health’s Department of Epidemiology.
“But until this study, we didn’t have the proof necessary to say that daily exercise, sustained over several years, truly can prevent loss of mobility. Doctors can now feel confident that moderate physical activity improves the independence and mobility of older adults.”
Newman and her fellow investigators, coordinated by Marco Pahor, M.D., director of the University of Florida’s Institute on Aging, obtained those results through the Lifestyle Interventions and Independence for Elders, or LIFE study. This study recruited and followed 1,635 sedentary men and women — 216 from Pittsburgh — aged 70 to 89.
Newman, a geriatrician, supervised the Pittsburgh arm of the LIFE study. For the national study, she chaired the ancillary studies review committee and wrote the outcome procedures for cardiovascular events and the procedures for participant medical clearance at enrollment and for return after illness.
The study showed that prescribed daily physical activity would prevent older adults’ loss of mobility, defined in the study as the inability to walk 400 meters, or about a quarter of a mile. That is approximately equal to a trip from a parked car to a grocery store or a walk through a neighborhood.
Moderate physical activity helped aging adults maintain their ability to walk at a rate 18 percent higher than older adults who did not exercise. It also resulted in a 28 percent reduction in people permanently losing the ability to walk easily.
“This large impact on reducing persistent disability is important,” said Newman. “Beyond simply maintaining mobility, this shows that we can repair a deficit through physical activity.”
When recruited to the study, participants could walk a quarter mile within 15 minutes, but were at risk for losing that ability. Low physical performance can be a predictor of early death and higher hospitalization rates. Patients with low physical performance are not often recruited to large studies, making it difficult to give research-backed medical recommendations.
“These are people who are patients we see every day. This is why this study is so important: It includes a population that is typically understudied,” said Pahor.
The participants were randomly sorted into two groups. For two years, the first group walked 150 minutes per week and did strength, flexibility and balance training. Twice each week, they visited field centers, which kept them on track with their exercise. The second group attended health education classes and performed stretching exercises. This phase of the study occurred between February 2010 and December 2013.
Research technicians assessed study participants every six months, checking their ability to walk, their body weight, blood pressure and pulse rate, among other measurements. The staff was not told which participants were assigned to physical activity or to the education classes.
At Pitt, nearly two dozen researchers, students, technicians, nurses and exercise physiologists ensured the trial and data collection ran smoothly. All eight field centers regularly communicated with one another to share tips for encouraging participants to stay in the study.
The researchers noted that there is still a vast amount of data available from the study that needs to be analyzed, including looking at the effects of physical activity on the participants’ cognitive function. The research team also plans to determine how physical activity affected the participants’ physiological, social and biologic factors.
In addition to Pitt and the University of Florida, LIFE study field centers include Northwestern University, Pennington Biomedical Research Center, Stanford University, Tufts University, Wake Forest University and Yale University.
In Pittsburgh, primary faculty on the LIFE study are Stephanie Studenski, M.D., Ph.D., Bret Goodpaster, Ph.D., Nancy Glynn, Ph.D., and Oscar Lopez, M.D., all of, or formerly of, the University of Pittsburgh.