Indiana University       Research & Creative Activity      September 2001 • Volume XXIV, Number 2

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What's the secret to staying on
our toes when we grow old? Get physical.

Lives in the
Balance

by Erika Knudson

Imagine a 70- or 80-year-old person carefully traversing a tightrope or standing sure-footed on a steel beam high above a construction site. For that matter, picture that older person walking across a just-mopped kitchen floor, leaning forward, and lifting a gallon of milk out of the refrigerator.

Whether the older person’s activity is extraordinary or everyday, personal safety and well-being hang in the balance, literally. With that first step onto the kitchen floor, a complex choreography of signals and responses enters the brain’s stage, arabesques through the spinal cord, and lands in the body’s muscle fibers. As David Koceja’s research on balance and posture control in older adults demonstrates, how quickly those signals are sent, whether they make it to your muscles—and whether you are ultimately standing, swaying precariously, or sprawled across the floor—are determined not just by the aging process, but also by your level of activity and fitness.

In his Motor Control Research Laboratory at IU Bloomington, Professor of Kinesiology David Koceja studies how older adults use, and lose, their sense of balance. Photo © 2001 Tyagan Miller

Koceja, professor of kinesiology in the IU Bloomington School of Health, Physical Education and Recreation, has a full complement of analogies, similes, and metaphors to describe his research into the complexities of balance, aging, and activity. His comparisons range from choreography to a bag of large and small marbles, from a car trip in a blizzard to the structure of the universe.

The plot is something like this: every muscle in the body has a corresponding set of neurons in the spinal cord, and the communication between muscle and neuron is precisely choreographed. When muscles are inactive, Koceja says, the brain stops sending signals to them.

“Let’s look at an extreme example—say your arm is in a cast,” he says. “Those muscles would immediately stop working. You’d try to use them after the cast came off, and your brain would say, ‘We haven’t done this in a long time, and we’re not going there.’”

Aging and inactivity cause motor neurons to go dormant. To return to the choreography analogy, it’s as if one of the dancers in a pas de deux suddenly stopped on the stage and forgot how to lift his partner up in the air.

There are three systems of the central nervous structure that control balance—visual, vestibular (controlled by the inner ear), and it’s reflexes. Working in the Motor Control Research Laboratory in the basement of the HPER building, Koceja and his graduate assistants use strategically placed electrodes to test the response of neurons and muscles in each of the systems of balance. They use the results of these tests to evaluate older adults’ balance and postural control. If the tests show that one or more of a subject’s balance systems is malfunctioning, Koceja says, he recommends interventions, and “the number one intervention is physical activity.”

Because the central nervous system has the ability to retrain neurons, an inactive person can regain use of dormant neurons and muscles—and thus, improve balance—through physical activity. In Koceja’s research comparing spinal control of balance in older and younger adults, funded by a National Institutes of Health grant, people who did strength training three times a week for five weeks got 40 percent stronger and were able to significantly regain their physical stability and balance.

“If the nerves in your body spend 40, 50, 60 years not doing anything, your brain stops calling on them,” Koceja says. “But if you start a training program, it’s remarkable how quickly the brain remembers those nerves.”

In some situations, motor neuron function can be completely lost. This is the case with stroke patients, for example. But it’s like a trip to the airport during a bad snowstorm, says Koceja: “You have to get to the airport, and the main road is totally snowed in. Can you get there? You could if you took another road.

The ancient Chinese discipline of T'ai Chi is one fothe most effective activities for older addults seeking to improve or restore their sense of balance. Photo Barbara Hawkins.

“Say you’ve had a stroke and part of your central nervous system is damaged,” he continues. “At first you can’t use your right hand. But you can try a lot of other neural paths to try to get there. The brain has an almost unlimited capacity, based on the situation and the need.”
The key to the neuromuscular map of balance is variety of activity. The interventions that Koceja prescribes for inactive older adults with poor balance range from T’ai Chi to weight training to water sports. In some cases, Koceja designs special balance programs in which clients walk on foam, climb up ramps, and traverse balance beams.

As he rocks back and forth, demonstrating a balance board—a scooter-sized square of wood with a half-sphere rocker on the bottom—Koceja says that any level of exercise will help. “But after a certain point,” he adds, “you need to do more specific work directed at retraining the neurons and muscle fibers associated with balance.”

That little square of rocking wood can get older adults rolling toward independence, freedom, a richer social life—in short, the ability to do what they want. “If you’re afraid of breaking a hip,” says Koceja, “you can become immobilized. If you don’t feel safe going for a walk, you’re trapped inside the house, and that affects your quality of life.”

By now, the ideal routine for maintaining good balance and postural control—and thus, a good quality of life as you age—is common knowledge: exercise at least three times a week, including aerobic exercise, a flexibility (stretching) regimen, and some strength training.

“And maintain that through life. Why not? It’s free!” says Koceja, 43, who plays golf, bikes to work in the summer, and walks a lot. (Until a recent knee injury put him out of commission, Koceja was also a serious runner; he’s completed both the Chicago and the Milwaukee marathons.)

Even older adults who have led inactive lifestyles can adopt this routine if they work up to it. “You can gradually regain a high level of fitness—beginning with slow walking and building up to strength training,” Koceja says. “The exciting part about the work that we’re doing is that people will recover. The problem is motivation.”

Koceja’s mission to motivate older adults to lead more active lives takes him and his graduate students to the Meadowood retirement community on the IUB campus and a local center for senior citizens, where they give talks and seminars based on their research findings. In a developing partnership with Bloomington Hospital Rehabilitation Services, they offer balance screenings for elderly patients in rural areas. And they do screenings at the local YMCA twice a year. Koceja is also hopeful that the YMCA will offer a balance class in the future.“They do cardiac rehab there, and have a lot of people concerned with their balance,” he says.

Koceja’s ongoing research includes investigating the effects of Parkinson’s disease on the neurological paths that determine balance and postural control and working with HPER colleagues Janet Wallace and Vassilios Vardaxis to determine the efficacy of exercise in improving nerve function in diabetes patients. But perhaps the most important outgrowth of all his work is offering information and inspiration to the people who need it.

“Getting this information to practitioners and patients is so crucial,” Koceja says. “We’re doing a decent job in Bloomington of linking our research with people in the community. But I still think a lot of people aren’t getting this information, and I want to do everything I can to change that.”

Koceja is passionate about his research because he sees it making a direct impact.

“There’s definitely a meaningfulness in having something to do with making a person’s quality of life better,” he says. “I love the people I work with. I want to be 90 years old and have as good a disposition as my research subjects.”

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