Research Suggests Increased Lower Body Strength Promotes Independent Lives for Seniors

July 7, 2010

A recent study done by a collaboration of researchers from Wake Forest University (WFU) and Wake Forest University Baptist Medical Center (WFUBMC) suggests that a significant number of residents living in retirement communities have deficits in lower body strength, a key indicator in estimating how independent seniors may remain in the future. A follow-up study found a resistance exercise program was effective at improving muscle strength within six weeks. 

The study, conducted by investigators in the Department of Health and Exercise Science at WFU and the Department of Geriatric Medicine at WFUBMC, was developed in conjunction with Homestead Hills, a Winston-Salem, N.C.-based retirement community, and the Center on Aging at WFUBMC. Through a partnership with Homestead Hills’ parent company, researchers from the Center evaluated the physical function of approximately 230 older adults living in retirement communities throughout the Southeast.   

The researchers, including Jack Rejeski, Ph.D., Tony Marsh, Ph.D., Shannon Mihalko, Ph.D. and Jeff Williamson, M.D., M.H.S., found a high proportion of participants had deficits in lower extremity strength. The follow-up study by Rejeski, Marsh, and Mihalko measured the impact of lower-body strength training on muscle strength and physical function in those residents. All 29 seniors who participated were Homestead Hills members and the participants were randomized into two groups: a control group whose members maintained their normal daily routine, and a progressive resistance exercise group which met for about 30 minutes, three times a week for six weeks. 

To develop a baseline, all 29 adults were evaluated at the beginning and end of the six-week intervention. Their lower-body strength and physical function were measured by a one repetition, maximum strength test for both the leg extension and leg curl, a timed 400 meter walk test and the Short Physical Performance Battery which tests walking speed, balance and lower- limb strength.

The progressive resistance exercise group completed a variety of exercises designed to increase leg strength. Residents wore weighted vests for resistance while performing toe raises and step-ups on an aerobic step, and used strength training equipment for leg extension and flexion exercises. 

Adults who participated in the lower-body strength training exercises had an average increase in leg extension strength of 51 percent and an average increase in leg curl strength of 31 percent, while the strength of those in the control group did not change.   

Participants such as Roburta Trexler, a retired physical therapist, also reported increased confidence in their walking ability.

“I feel like I’m definitely making some improvements,” Trexler said, while resting in between exercises inside Homestead Hills’ wellness center. “When I walk across the floor, I feel more secure, and I plan to continue with the exercises because I would like to walk with a feeling of confidence, improve my posture and stand up without hurting.” 

Lower body strength is vitally important because it is a key determinant of mobility which allows older adults to perform activities of daily living such as bathing, dressing and getting in and out of bed without the help of a caregiver. Research suggests that strength-training exercises also improve balance, helping participants reduce their chance of falling which may lead to disability, hospitalization and other negative complications. 

Ruth Kessler, a member of the progressive resistant exercise group, is all too familiar with the side-effects of a catastrophic fall. The Homestead Hills member fractured her left femur two years ago, and the recovery has been long and difficult.

“At the beginning of the six-week period, it was extremely difficult for me to get up from a seated position,” Kessler said. “After I finished the sessions, I progressed from lifting 40 pounds to lifting 70 pounds with my leg curls, and I can do five chair-stands now when I couldn’t even do one before.” 

At the end of the six-week intervention, the control group was offered six weeks of training, and the participants in the exercise group were encouraged to continue with the resistance exercise program. Due to popular demand, Homestead Hills Wellness Coordinator Sandi Griswold is planning to extend the program indefinitely. 

“Once members found out they were in the control group and saw the results their counterparts were having, they couldn’t wait for the end of the first six weeks so they could get started,” Griswold says with a laugh. “Their enthusiasm is contagious, and with all the information WFU and WFUBMC have collected, the program is a way to not only improve our members’ lives but also to better the lives of thousands of seniors across North Carolina.” 

The Department of Health and Exercise Science and the Center on Aging will use the data collected at Homestead Hills to recommend that providers develop senior wellness programs which emphasize preventative, affordable exercises that help older adults live healthier, more independent lives. In addition to the partnership with Senior Living Communities, pilot grants from the WFUBMC Translational Science Institute and the WFUBMC Claude D. Pepper Older Americans’ Independence Center supported the study. 

Homestead Hills’ member Sally Bost agrees that preventative wellness programs are beneficial for seniors and thinks the amount of effort people put into the program is directly related to the benefits they will receive. The 76-year-old also thinks retirement communities are a good solution for older adults because of the combination of peer support and senior-focused amenities. 

“I needed the encouragement of my friends and fellow members to keep myself honest in my exercise,” Bost said. “It’s too easy to say, ‘Oh you’re getting older, this is what you should expect.’ But I say, ‘No way! You can’t quit just because you’re older!’”

Media Relations

Jessica Guenzel: news@wakehealth.edu, 336-713-4587

Bonnie Davis: bdavis@wakehealth.edu, 336-713-1597