Washington People: Gammon Earhart

Reviving freedom of movement with tango

Gammon Earhart (black pants) dances the tango with Stephen Berra, a patient with Parkinson’s disease. On the left are Parkinson’s patient Don Burr and his wife, Karen Burr. Earhart’s research demonstrates the benefits of tango dancing on patients with Parkinson’s. (Credit: Robert Boston)

Gammon Earhart stumbled across the practice of physical therapy by accident.

While in high school, she thought she wanted to become a special-education teacher, so she participated in a program at a school for children with disabilities near her hometown of Oxford, Pa.

“When I saw the children working with physical therapists, that’s what sparked my interest in PT as a career,” said Earhart, PhD, a professor in the Program in Physical Therapy at Washington University School of Medicine in St. Louis. “I saw such a big difference in the kids when they were in class compared with when they were in therapy. In therapy, the freedom of movement was so different – the kids lit up. So I decided I wanted to do that.”

Little did she know then just how much freedom of movement would mean to her in her career. Arguably Earhart’s most significant contributions as a professor of physical therapy have been her studies demonstrating the benefits of tango dancing on patients with Parkinson’s disease.

But long before she arrived at that point, she had to maneuver another career-focused crossroads.

While finishing her bachelor’s degree in psychobiology at Arcadia University in Pennsylvania, she found herself torn between pursuing a master’s in physical therapy at Arcadia — or setting her sites on a PhD in ecology, with a focus on turtles.

She had developed an interest in turtles while in middle school, “and it started with Saturday Night Live,” she said. “There was an animated feature called ‘Tippi Turtle,’ and he was a bit of a prankster. I thought it was really funny, so I’d go around the house singing the theme song while bobbing my head and making a funny face.”

It resulted in the nickname “Turtle” from her dad. The nickname still endures.

Earhart’s fascination went beyond fictional turtles, however. While at her father’s hunting cabin in rural Pennsylvania, she would observe turtles in the wild, measure and track them and keep notes in a journal. The next year, she would try to determine if the turtles she saw were the same she’d seen the year before.

Then, during the summer between her sophomore and junior years in college, she went to Guyana for a sea turtle conservation project. There, she monitored a nesting area and took newly laid eggs to a safe place to protect them from predators and poachers.

“We also educated the local people, who were dependent on the turtles or their eggs for food,” she said. “We taught them how to raise chickens as alternative food sources. We would also have groups of children from the local villages spend a week on the beach with us so they could get an appreciation for the turtles’ nesting process,” she said.

Gammon Earhart talks with Yvonne Schraut, a participant in an exercise trial, as Schraut walks on a treadmill for the study. (Credit: Robert Boston)
Earhart ultimately decided she wanted to work with people, so she opted for the physical therapy track and enrolled in Arcadia’s master’s program in physical therapy. She still had the urge to do research, so her mentor and neuroscience professor at Arcadia, Becky Craik, introduced her to Paul Stein, professor of biology in Arts & Sciences at Washington University in St. Louis.

The introduction resulted in an unlikely merging of two of her greatest interests.

“Becky knew I loved turtles, and she knew Paul was using turtles as a model for spinal cord control of movement,” Earhart recalled. “That introduction led me to apply to the Movement Science PhD program here.”

Earhart’s thesis was a combination of two turtle studies and two human studies. Her first two years were spent working solely with Stein in his biology lab, using turtle models to research what the spinal cord can do in terms of movement control when it is completely isolated from the brain and brain stem.

The following two years, she split her time between Stein’s lab and the lab of Amy Bastian, PhD, then assistant professor of physical therapy (now a professor of neuroscience and neurology at Johns Hopkins University). In Bastian’s lab, her focus shifted back to people — specifically, the human cerebellum’s role in walking, both in healthy people and those with cerebellar damage.

For her postdoctoral work, Earhart headed west to Oregon Health and Science University for more studies of walking, focusing on how people adapt their walking patterns when they encounter unusual situations.

“We had people walk on a rotating treadmill, which looks like a giant turntable,” she said. “Then we asked the participants to walk in a straight line, and we found they couldn’t; the process forces them to turn.”

In July 2004, Earhart brought her research back to Washington University’s Program in Physical Therapy, where her work with Parkinson’s disease patients began.

“Turning is something people with Parkinson’s disease are particularly troubled by,” she explained. “They try to make a turn but sometimes get stuck and feel like their feet are glued to the floor. This can lead to falls and consequences related to falls.”

The next year, at an annual meeting of the Society for Neuroscience, she was led, so to speak, to the dance floor. There, she saw an abstract from Canadian researchers focused on frail, elderly individuals randomly assigned to either walk in a group for exercise or learn to dance the tango. The findings indicated that those assigned to dance had improved their walking more than the walking group.

Madeleine Hackney, PhD ’09, a professional dancer-turned-graduate student, had begun working in Earhart’s lab, and the two decided to try a pilot study incorporating the tango for people with Parkinson’s.

The outcomes of the pilot study showed that, when compared with a group of people who had taken a traditional exercise class, there were more significant improvements regarding balance and walking among the people in the tango group.

Subsequent studies also have shown that tango-dancing participants experience improvements that are as good as or better than those who exercise using other forms of dance, such as the waltz, fox trot or other alternative approaches, such as tai chi.

The most important finding resulted from a study in which people with Parkinson’s danced the tango twice a week for a year. Participants were evaluated before they started dancing and then again after three, six and 12 months. This group was compared with another group of people who had Parkinson’s but did no exercise during the same time period.

Earhart and her husband, Paul Markowitz, and son, Maelon, while on a ziplining adventure. (Credit: Courtesy of G. Earhart)
“We noted that at three months and then again at six and then 12 months, the people who were participating in tango dancing were improving instead of deteriorating, which is unexpected for people with a neurodegenerative disease like Parkinson’s,” said Earhart, who is also a professor of anatomy and neurobiology and neurology. “That suggested we were potentially modifying the trajectory of the disease’s progression with participation in the tango exercise program. That could have very positive ramifications.”

Earhart is continuing her tango studies but has included a neuroimaging component to see what parts of the brain may be affected by dancing compared with other forms of exercise.

Her ongoing work involves neuroimaging and imagined walking tasks in people with Parkinson’s who experience freezing of gait.

She finds her work most satisfying after a study concludes, when she sees how therapy has helped people – just like she did when she was in high school, observing kids with disabilities in therapy.

“It is rewarding to know that people are directly benefiting from participating in the exercise interventions we offer and wonderful to hear participants’ stories relating how involvement in our research has enhanced their quality of life.”

Meanwhile, freedom of movement seems to have become a theme for Earhart that extends beyond her work.

She has a black belt in karate, an activity she grew interested in while watching her then-4-year-old son, Maelon, take karate classes. “After about a year, I decided I would take classes, too,” she said.

Soon after, her husband, Paul Markowitz, PhD, joined in. Now, Maelon, 10, and his parents each have a black belt.

In addition, the family enjoys ziplining, as well as hiking and camping in state parks throughout Missouri and Illinois.

“There is nothing quite like a family walk in the woods,” Earhart said, “especially one where we happen to spot a turtle.”