Explore Magazine Volume 3 Issue 1


Out Of The Locker Room, Into The Laboratory
UF's Department of Exercise and Sport Sciences reflects the evolution of the discipline from the gymnasium to the laboratory.

By Joseph Kays

When Robert Singer began his academic career in the early 1960s, some of the disciplines he now supervises as chair of UF's Department of Exercise and Sport Sciences didn't even exist.

"When I started college, all I really wanted to be was a gym teacher," says Singer. And the academic structure of higher education was ideally suited to Singer's ambitions.

"I think my own experience embodies the changing nature of the field," Singer says. "Just as I was going through graduate school, my discipline began evolving from one that primarily prepared physical education teachers and coaches to one that focused on all aspects of physical well-being."

Singer, too, evolved from a successful collegiate basketball and baseball player and aspiring phys ed teacher into one of the country's foremost experts on sport psychology and motor behavior. A past president of the International Society of Sport Psychology and the American Academy of Kinesiology and Physical Education, Singer now chairs one of the top four exercise and sport sciences departments in the country.

By the time the fitness boom of the early 1970s hit, this evolution was well under way and by the mid 1980s, many colleges and universities were revising their curricula and even their names. The University of Florida changed the name of its College of Health, Physical Education and Recreation to the College of Health and Human Performance in 1985.

Singer says the department's close relationships with UF's intercollegiate athletic program and the colleges of medicine, engineering, liberal arts and sciences, health professions and business have all helped to strengthen its position in the field.

"Another boost for this field was the development of big-time sports programs at the college and professional level," Singer says. "When the general public saw sport scientists helping college and pro athletes, they realized what might be available to help their game.

"If Michael Jordan wears Nikes, everybody wants to wear Nikes," Singer continues. "If (Atlanta Braves pitcher) John Smoltz uses a sport psychologist, weekend warriors think about using a sport psychologist."

In fact, sport psychologist Jack Llewellyn, who is credited with turning Smoltz's career around, is a former doctoral student of Singer's.

Today, the laboratories and centers housed within the Department of Exercise and Sport Sciences are testament to this new emphasis. With titles like Exercise Physiology Laboratory, Motor Behavior Laboratory and Biomechanics Laboratory, the emphasis has clearly shifted to the science of exercise and personal well-being.

In addition, the department administers the renowned Center for Exercise Science, under the direction of Dr. Michael Pollock. The center, whose research findings are regularly cited in both scholarly and popular publications, is managed under a collaborative agreement between the colleges of health and human performance and medicine.

Exercise Physiology Laboratory

Scott Powers' laboratory rats are the only motivation the UF professor of exercise physiology needs to exercise regularly and take antioxidant vitamins daily.

"When you compare the damage from heart attacks in trained and untrained rats, you can't help but be convinced that regular exercise and dietary antioxidants like Vitamins E and C help to protect the heart," Powers says. "If we all live long enough, there is an excellent chance that we are going to experience heart blockage at some time. When this happens, our only hope is to limit the damage that occurs to the heart muscle."

With grant support from the American Heart Association-Florida, Powers' research team has been investigating the potential benefits of both regular exercise and dietary antioxidants in protecting the heart against injury during heart attacks.

The research team has induced blockages, known as ischemia, in the left coronary artery of experimental rats following 10 weeks of treadmill exercise. Sedentary rats served as controls.

"During the 20 minutes the artery was blocked, blood pressure in the trained animals declined only slightly, whereas blood pressure in the sedentary rats dropped dramatically," Powers says, pointing to a graph that illustrates the wide gap in blood pressures between the trained and untrained animals during the simulated heart attack. "The hearts in the trained rats just kept pumping along in spite of the blockage."

While there have been numerous epidemiological studies suggesting a positive connection between exercise and heart health, experimental studies in this area are few. Powers believes this is the first research to comprehensively examine how trained and untrained hearts perform in the body in response to a simulated heart attack.

"We are now trying to explain why exercise training provides the heart with protection during a heart attack," he says. "By determining the mechanism responsible for this exercise-induced cardiac protection, we can then develop clinical strategies to better protect the heart against this type of insult."

In addition to studying the role exercise plays in the heart's ability to withstand damage, Powers' research team - which includes exercise physiology associate Professor Stephen Dodd, Dr. Michael Cicale of UF's College of Medicine, physical therapy Professor Danny Martin and graduate students Haydar Demirel, Karyn Ward, Jeff Coombes, Andy Shanely and Heather Vincent - is studying the role antioxidants play in heart health.

Antioxidants are chemicals that neutralize a damaging form of oxygen molecule, called a free radical. Free radicals contain an unpaired electron which makes them reactive and dangerous, resulting in cellular injury and even cell death. Indeed, many scientists now believe free radicals could be the cause of certain types of cancer, heart disease and even aging itself.

"Heart cells deprived of blood and oxygen undergo a chemical alteration that makes them vulnerable to the creation of free radicals when blood flow is restored," Powers says. "While antioxidants do not improve heart performance during the ischemia, when blood flows through again, the damage to the heart muscle is significantly less."

Future research will determine if the combination of exercise and dietary antioxidants provides even more protection to the heart against damage incurred during a heart attack.

Powers' team also is investigating the problem of weaning patients who cannot breathe for themselves, such as those recovering from surgery or suffering respiratory failure, from mechanical ventilators.

Powers and his research team have shown that prolonged mechanical ventilation weakens the diaphragm muscle that controls inhaling and exhaling. Powers believes diaphragm weakness may be a major factor in the inability to wean patients from the machines.

With funding from the American Lung Association-Florida, the researchers are now trying to determine what causes the diaphragm to weaken so dramatically.

"It's no fun to be on a ventilator, and it's a terrible economic burden. So what's wrong? Why is it so hard to wean people off of them?" Powers asks.

Physicians have long attributed the problem to atrophy of the diaphragm muscle, but Powers' research demonstrates the diaphragm weakness can occur within 18 hours after the patient is put on the ventilator.

"Atrophy just doesn't happen that fast. We could put a cast on your bicep today and it will not have significantly atrophied by tomorrow. It takes days, not hours or minutes," Powers says.

Initially, Powers' team is focusing on a specific biochemical change that causes the diaphragm to weaken.

"Our ultimate goal is to determine the mechanism responsible for ventilator-mediated respiratory muscle weakness and develop a clinical strategy to prevent or correct the problem," he says.

Motor Behavior Laboratory

Luvenia Crum was born and raised in the South, and until she suffered a stroke 17 months ago, she could often be found preparing traditional Southern foods like cornbread or fried okra.

But the cerebrovascular accident in Crum's brain created a roadblock in the route between the motor cortex of her central nervous system and her arm, disrupting the signals that controlled her muscles. The result was paralysis in her left arm that made it difficult or impossible for her to perform such simple daily tasks as slicing vegetables.

Fortunately for Crum, researchers at UF's Motor Behavior Laboratory were looking for people with just her type of paralysis to serve as subjects in an experimental therapy.

James Cauraugh has always been interested in motor control and "elegant movement."

"Understanding and trying to explain motor actions is fascinating to me," says Cauraugh, director of the Motor Behavior Laboratory in the Department of Exercise and Sport Sciences. "From a motor control perspective, there is nothing more beautiful than the way Michael Jordan moves a basketball from his right hand to his left while flying under the basket to execute a reverse lay-up."

But while he has worked with elite athletes during his career, Cauraugh gains the most satisfaction from helping people learn or relearn basic movement skills. Especially gratifying, he says, is helping people disabled by diseases like stroke, Parkinson's disease and polio reacquire basic movement skills.

With pilot funding from the Office of Research, Technology and Graduate Education's Opportunity Fund, Cauraugh and colleagues Kathye Light and Andrea Behrman from the College of Health Professions and William Triggs of the College of Medicine are applying that interest in motor behavior to helping stroke patients like Crum.

The research team is in the process of testing a dozen stroke patients to determine if biofeedback-triggered electrical muscle stimulation can help a patient's neuromuscular system develop an alternative route between their central nervous system and their muscles. Specifically, they are trying to improve the wrist extension control of people who had a stroke more than a year ago.

"The theoretical basis of biofeedback-triggered neuromuscular stimulation is that alternative motor pathways can be recruited and activated to assume the function of pathways that were damaged by the stroke," Cauraugh says.

Researchers have found that, following a stroke, the paralyzed muscles do not receive sufficient electrical impulses to trigger a muscle contraction and subsequent movement.

Cauraugh has worked with the Dutch medical electronics firm Danmeter on the development of a device called an Automove 800, which simultaneously monitors electrical activity in the affected muscles and then triggers neuromuscular electrical stimulation to help the patient complete the movement.

The device constantly adjusts the target threshold - when the electrical stimulation kicks in - based on whether a patient successfully completes a wrist movement.

"Individuals are constantly challenged to increase their muscle activity voluntarily," Cauraugh says, "because the Automove unit continually raises the threshold level for stimulation after a successful trial."

The results of the trial to date have been encouraging, and Cauraugh is hopeful that challenging neuromuscular systems to "detour" around damaged pathways with devices like the Automove will become an established part of rehabilitation in occupational and physical therapy for stroke patients.

For Luvenia Crum, the treatments she received as a subject in Cauraugh's research project already have enabled her to resume some of her favorite activities, including cooking.

Biomechanics Laboratory

The illustration on Jeff Bauer's computer monitor speaks volumes about his diabetic patient's foot problems.

Drawing on feedback from a state-of-the-art insole pressure monitor placed inside the patient's shoe, Bauer has created a graphical map of the way the patient's foot hits the floor, and it's not normal.

"Diabetes often results in vascular constriction, especially in the lower extremities," Bauer says. "As blood flow diminishes, nerves die off and the patient's feet become numb. When they can't feel their feet, diabetics typically change the way they walk, putting too much pressure on certain parts of the sole. This pressure literally pushes the bone through the soft tissue of the foot, causing ulcers, which often result in partial or total amputation of the foot."

Bauer helped engineer the controller unit for the Parotec Insole System as part of his doctoral research at Penn State University. That system is now one of the central instruments used at the Biomechanics Laboratory in UF's Department of Exercise and Sport Sciences. Although widely used in Europe, UF's system is one of only two currently in operation in the United States.

The researchers are collecting normal walking patterns and comparing them against the patterns of people whose walking pattern has been disrupted in some way.

Bauer, his students and colleagues have used the array of sensors in the thin insole on such diverse groups of subjects as golfers, javelin throwers and police officers. But it is the device's potential to help diabetics, post-polio patients and other high-risk populations that most excites him.

"This is a very important tool," Bauer says, "because many Americans will develop some sort of foot-related disability at some point in their lives."

"A lot of times, patients don't even believe their walking style is abnormal until you show them on the monitor," Bauer says. "Often, that's all that is needed to get them to adjust their stride."

Ultimately, Bauer and the insole manufacturer, German-based Paromed Medzintechnik, hope to develop a portable home version of the device that can be programmed to give patients biofeedback when they walk incorrectly during their daily activities.

"We can program the insole to alert a patient when pressure on different parts of the feet reaches a certain level," Bauer says. "We hope that this kind of biofeedback will help them modify the way they walk."

Another initiative of the Biomechanics Lab has special significance to Bauer.

"I've been playing tennis much of my life," says the former member of Penn State's intercollegiate tennis team, "and I've had tennis elbow for years.

"Tennis elbow is kind of like a migraine," he continues. "People often don't understand the pain you're in because there is nothing bleeding or broken."

By electronically monitoring the way healthy and injured tennis players grip their rackets, Bauer has been able to show that tennis players with elbow injuries compensate for their injury by gripping the racket tighter, tensing the muscles of their lower arm in anticipation of the ball's impact.

" Tension is the wrong thing to use," Bauer says. "It's like gripping a baseball bat tighter on a cold day. It stings more when you hit the ball."

Bauer says only 5 percent of the people who get tennis elbow, known medically as lateral epichondyle tendonosis, are tennis players, so this research has implications far beyond the tennis court.

"This research has applications to many work-related injuries that involve damage to the elbow in some way, such as construction work and truck driving," Bauer says.

With a grant from the United States Tennis Association, Bauer and his colleagues are evaluating how various types of elbow braces work to alleviate tennis elbow.

"Elbow braces have been used in tennis for a hundred years and they seem to work, but nobody really understands why," Bauer says. "Our research indicates that braces ease the initial pain, so a player doesn't begin the destructive spiral of changing his or her mechanics, gripping the racket harder and making the problem worse."

Through the USTA grant, Bauer is exposing volunteer subjects to 20 different combinations of mechanically induced vibrations while wearing different elbow braces.

"We use a mechanical vibrating machine to create quantifiable vibrations against the face of the tennis racket," he says. "We are attempting to identify the frequencies of vibrations that seem to cause the most pain, and then tune the braces to dampen those frequencies."

 Jeff Bauer, Assistant Professor, Department of Exercise and Sport Sciences, (352) 392-0584, jbauer@nervm.nerdc.ufl.edu

James Cauraugh, Associate Professor, Department of Exercise and Sport Sciences, (352) 392-0584, jcaura@hhp.ufl.edu

Scott Powers, Professor, Department of Exercise and Sport Sciences, (352) 392-0584, spowers@hhp.ufl.edu

Robert Singer, Professor and Chair, Department of Exercise and Sport Sciences, (352) 392-0584, rsinger@hhp.ufl.edu

Related web sites: http://www.hhp.ufl.edu/ess/    http://www.hhp.ufl.edu/