Last modified: Monday, June 6, 2011
IU researchers discuss barefoot running, stroke and yoga, virtual worlds and more at ACSM
Studies involving dozens of Indiana University researchers were displayed and discussed during the American College of Sports Medicine's 58th annual meeting May 31-June 4 in Denver. Below is just a sampling of the research.
Barefoot running: When to ditch the shoes
Weight loss success in a 3D virtual world
Older adults who had strokes give yoga a try
Strength in numbers: Elite athletic performance
Health disparities involving physical fitness
Stronger hips improved running mechanics, lessened knee pain
Run like a caveman? A hot issue among runners is whether running in bare feet reduces or increases the risk of injury. Stuart Warden, associate professor and director of research in the Department of Physical Therapy at Indiana University-Purdue University Indianapolis, says for some runners it could do both. The reason it could do both, Warden said, has to do with whether you grew up running in standard athletic shoes. For those who wish to switch from wearing shoes to running barefoot, there is more to do than throwing away their sneakers, Warden cautioned. Otherwise, the risk of injury could increase. "The heel cushions and arch supports within modern shoes have made our feet weaker," Warden said. "The foot has so much support in these shoes that the muscles don't need to work as much as they would otherwise and have grown weaker . . . If you transition to barefoot running slowly and run correctly, so you build up to it, you could decrease the risk of injury over the long term." Runners who suffer repeated running-related injuries and can't overcome them through rehabilitation may want to consider switching to barefoot running, Warden said. For recreational runners who are happy running in shoes and don't suffer repeated injuries, there is no need to switch, he added. "There is no point in changing something that is not broken."
- Barefoot v. running shoes: The feet of runners land differently, depending on whether one is running in bare feet or in athletic shoes with a big cushion under the heel, Warden said. The shoes encourage the runner to strike the ground with heels first. The shoes also place the foot in a down position that makes it difficult to comfortably land on the front part of the foot. Barefoot running encourages the runner to land on the forefoot or balls of the feet. Barefoot runners could land on their heels, if they chose to, but it would be painful, he noted. When the heel strikes the ground in a shoe, there is an impact force that courses up through the foot and into the body, Warden said. The prevailing theory is that the impact force is related to stress fractures and other injuries associated with running. By decreasing those forces, the risk of injury is reduced. When barefoot runners' feet strike the ground, the runner is landing on the front or middle of the foot and the heel is lowered to the ground, he noted. The impact force is less and the risk of potential injury is lower.
Warden discussed the issue in a symposium "Barefoot Running: So Easy, a Caveman Did It!" on Thursday. He is presenting with two Harvard University researchers, Daniel Lieberman and Irene Davis, who co-authored a research paper last year on the topic.
Out of this world. Participants in two weight-loss programs -- one involving traditional health club sessions and the other delivered online in a 3D virtual world -- lost similar amounts of weight and body fat, but the online contingent reported significantly greater gains in behaviors that could help them live healthier and leaner lives. "It's counter-intuitive, the idea of being more active in a virtual world, but the activities that they do in a virtual world can carry over into the real world," said Jeanne Johnston, assistant professor of kinesiology at Indiana University. "Through visualization and education, they can try activities that they had not tried before." More and more people have been turning to online weight-loss programs, but Johnston said the programs often lack important elements of human interaction. The IU researchers wanted to travel even farther into cyber space by evaluating a weight-loss program offered in a virtual-reality environment, where visitors use avatars to interact with others or the computer-simulated environment -- in this case, a simulated fitness club. "The virtual world program was at least as beneficial as the face-to-face program and in some ways, more effective," Johnston said. "It has the potential to reach people who normally wouldn't go to a gym or join a program because of limitations, such as time or discomfort with a fitness center environment."
About the study:
- For 12 weeks, members of the each weight-loss program spent at least four hours a week attending meetings at a virtual or real club. In both they learned about nutrition, physical activity, changing habits and how to benefit from social supports. The study involved overweight and obese people -- mostly women. The average age of the face-to-face group was 37. The average age of the virtual world group, which provided training in how to use the Web-based platform Second Life, https://secondlife.com/, was 46.
- The participants in each group lost a comparable amount of weight -- on average almost 10 pounds -- and saw similar decreases in body mass index and body fat. The big differences between the two groups involved behaviors. Participants in the face-to-face group reported no significant changes in any of the behaviors evaluated -- actions involving healthy eating, physical activity and sleeping habits. The virtual world participants reported positive changes in all the healthy eating and physical activity measures except the number of hours slept. "They also had more confidence in their ability to perform physical activity in difficult situations, such as bad weather, vacations, low-energy days," Johnston said.
In collaboration with Celeste De Vaneaux, creative director and CEO of Club One Island, the study was conducted by Jeanne D. Johnston, Anne P. Massey, Kelley School of Business, and Victoria S. Lee, a graduate student in kinesiology in the School of Health, Physical Education and Recreation.
Lee will discuss "Comparison of a Face-to-Face versus Virtual World Weight Loss Program" on Friday, June 3, 8-9:30 a.m., in a poster presentation in Hall B.
Yoga helped older stroke victims improve balance, endurance. An Indiana University study that exposed older veterans with stroke to yoga produced "exciting" results as researchers explore whether this popular mind-body practice can help stroke victims cope with their increased risk for painful and even deadly falls. The pilot study involved 19 men and one woman, average age of 66. For eight weeks, they participated in a twice weekly hour-long group yoga class taught by a yoga therapist who dramatically modified the poses to meet the veterans' needs. A range of balance items measured by the Berg Balance Scale and Fullerton Advance Balance Scale improved by 17 percent and 34 percent respectively by the end of the program. But equally exciting to lead researcher Arlene A. Schmid, rehabilitation research scientist at the Richard L. Roudebush VA Medical Center in Indianapolis, was the measurable gain in confidence the study participants had in their balance. "It also was interesting to see how much the men liked it," said Schmid, assistant professor of occupational therapy in the School of Health and Rehabilitation Sciences at Indiana University-Purdue University Indianapolis. Many of the veterans wanted the study to continue or asked for a take-home exercise plan so they could continue the practice. "They enjoyed it so much partly because they weren't getting any other treatment. They had already completed their rehabilitation but felt there still was room for improvement." Statistics concerning strokes and falls are grim, with studies showing that strokes can quadruple the risk of falling and greatly increase the risk of breaking a hip after a fall. An estimated 80 percent of people who have strokes will also have some degree of impaired balance.
More about the study:
- The study participants performed poses initially while seated in chairs and then progressed to seated and standing poses. Eventually, they all performed poses on the floor, something Schmid considers significant because of a reluctance many older adults have to working on the floor. "Everything was modified because we wanted them to be successful on day one," Schmid said. "Everyone could be successful at some level." A score of less than 46 on the Berg Balance Scale indicates a fall risk. Schmid said the study participants on average began the study with a score of 40 and then improved to 47, moving them past the fall risk threshold. The study participants also showed significant improvements in endurance based on a seated two-minute step test and a six-minute walk test.
Schmid said research into therapeutic uses for yoga is "really taking off," particularly in mental health fields. Clinically, she has been watching a small trend of occupational therapists and physical therapists also becoming yoga therapists. The yoga performed in the study was modified to the extent that Schmid said it would be very difficult to find a comparable class offered publicly. Such a class should be taught by a yoga therapist who has had additional training in anatomy and physiology and how to work with people with disabilities. Schmid hopes to expand the study so she and her colleagues can explore whether such classes are effective on a larger scale.
The study was funded by the Department of Veterans Affairs, QUERI. Study coauthors are Amanda N. Gerwig and Kristine K. Miller, IUPUI and Roudebush VAMC; Nancy Schalk, Heartland Yoga Community, Indianapolis; Marieke Van Puymbroek, IU Bloomington; Peter Alterburger and Tracy Dierks, IUPUI.
Schmid presented "Preliminary Evidence of Yoga on Balance and Endurance Outcomes for Veterans with Stroke" during a poster presentation on Saturday, June 4, in the session for Fitness and Performance Testing for Posture, Stability and Balance.
Strength in numbers. Russia is known for its chess champions. China for its table tennis. The U.S. has won more than three times as many Olympic swimming medals than any other country. What makes a country an international powerhouse in a given sport? Tradition, genetics, training? An Indiana University study suggests it could come down to numbers. Larger numbers of participants in a sport produce more elite athletes in that sport. The findings have "strong implications for national sport strategic policy," the IU researchers report. "Efforts to improve performance should be focused upon maximizing participation and minimizing dropout."
About the study:
- The researchers used USA Swimming data for the study because the organization divides the country into 59 regions for competition and collects performance and participation records for each region. The researchers analyzed the data for the 50-yard freestyle event along with the number of registered swimmers in 2008 for five different age groups, ranging from the 10 and under age group to the 17-18 age group. Their statistical analysis found that participation rates are a significant predictor of maximal athletic performance in that region.
But culture could play a role. "If a sport is important to an area, there could be more support for the sport, more facilities, so more people can do it," said Andrew Cornett, a doctoral student in the Department of Kinesiology at Indiana University Bloomington.
Cornett discussed his study during a poster presentation on Wednesday, June 1. Coauthor of the study is Joel Stager, Department of Kinesiology, School of Health, Physical Education and Recreation, IU Bloomington.
Study points to health disparities in physical fitness. An Indiana University study that is examining disparities in physical fitness levels between older adults who are patients of safety net community health centers (CHC) and those who are members of a medically affiliated fitness center is producing stunning results. NiCole Keith, associate professor in the Department of Physical Education at Indiana University-Purdue University Indianapolis, said she expected the study to show similar physical fitness levels between the two groups. The findings, however, show that the fitness center participants performed significantly better on each of the measures when compared to the CHC particpants. The community health centers serve vulnerable populations, including those without health insurance; the medically affiliated fitness centers serve a more affluent population. Otherwise, the age and health literacy of study participants in both groups were the same. Further, the members of the medically affiliated fitness center were not exercising at the facility every week, much less every day. Generally, these fitness center members had sedentary jobs. Patients at the CHC who were employed spent a lot of time on their feet and moving about. "I expected their physical fitness levels wouldn't be different, but they are so different that it is startling," Keith said. Seven indicators of physical fitness were tested, and members of the medically affiliated fitness center scored higher than the CHC patients in every category." The overriding difference between the two groups of study participants is access to opportunities to exercise, Keith said. For patients at the CHC, there is generally no place for them to exercise. The cost of joining a fitness center is prohibitive for these patients, she added. What is of great concern, Keith said, is that low levels of physical fitness are strongly related to negative health outcomes, including increased morbidity and mortality. The distinct differences among physical fitness levels between CHC patients and members of the medically affiliated fitness center demonstrate the clear need to identify low-cost and accessible means for vulnerable populations to improve their physical fitness levels, she said. Access to health care for all populations is important, Keith said, but it is not enough if it doesn't include opportunities to exercise.
More about the study:
- The study began in May 2010 and is expected to be completed in December 2011. To date, 150 subjects have been tested for physical fitness.
- Subjects who expressed interest in learning more about their physical fitness were invited to participate. Each subject completed the Rikili and Jones Senior Fitness Test, which includes functional assessments of lower body endurance, upper body endurance, aerobic endurance, lower body flexibility, right and left upper body flexibility, and percent body fat.
Keith discussed "Disparities in Physical Fitness Between Fitness Center and Safety Net Community Health Center Members" on Saturday, June 4, during a poster presentation. Coauthors of the study include Anthony S. Kaleth and Kyle McIlrath, IUPUI.
Stronger hips improved running mechanics, lessened knee pain. Hip strengthening exercises performed by female runners not only significantly reduced patellofemoral pain -- a common knee pain experienced by runners -- but they also improved the runners' gaits, according to Indiana University motion analysis expert Tracy Dierks. "The results indicate that the strengthening intervention was successful in reducing pain, which corresponded to improved mechanics," said Dierks, associate professor of physical therapy in the School of Health and Rehabilitation Sciences at Indiana University-Purdue University Indianapolis. "The leg was going through more motion, suggesting that the (pain) guarding mechanism was reduced, and coordination or control of many of these peak or maximum angles in the leg were improved in that they were getting closer to occurring at the same time." Only in recent years have researchers begun studying the hips as a possible contributor to patellofemoral pain (PFP). This study is the first to focus on hip strength and gait changes during prolonged running. Dierks, director of the Motion Analysis Research Laboratory at IUPUI, discussed his findings on Wednesday at the American College of Sports Medicine annual meeting in Denver. The runners in Dierks' study received no training or coaching on proper running form, which makes the improvements more notable. The improvements in mechanics resembled those of uninjured runners, when muscles, joints and limbs move economically and in synch with each other.
About the study:
- The study involved four runners and a control group comprised of another four runners. Hip strength measurements and kinematic data -- minute measurements of how the women's hips, knees and shin bones moved and rotated while they ran -- were taken before and after the runners in the control group maintained their normal running schedule for six weeks. The measurements were repeated for all of the runners before and after the next six-week period in which they all performed the hip-strengthening exercises. The exercises, performed twice a week for around 30 to 45 minutes, involved single-leg squats and exercises with a resistance band, all exercises that can be performed at home. This study is part of an ongoing study involving hip exercises and PFP pain, with 10 runners successfully using the intervention.
- After the six-week program, the movement of the hips and knees in relation to each other improved for both groups of runners, demonstrating increases in joint angles between the foot, shin and thigh.
- The study used a pain scale of zero to 10, with 3 representing the onset of pain and 7 representing very strong pain -- the point at which the runners normally stop running because the pain is too great. The injured runners began the six-week trial registering pain of 7 when they ran on a treadmill and finished the study period registering pain levels of 2 or lower; i.e. no onset of pain.
PFP, one of the most common running injuries, is caused when the thigh bone rubs against the back of the knee cap. Runners with PFP typically do not feel pain when they begin running, but once the pain begins, it gets increasingly worse. Once they stop running, the pain goes away almost immediately. Dierks said studies indicate PFP essentially wears away cartilage and can have the same effect as osteoarthritis. His study participants showed many of the classic signs of PFP, the most prominent being their knees collapsing inward when running or doing a squat exercise move.
Dierks discussed "The Effect Of Hip Muscle Strengthening On Pain and Running Mechanics In Females With Patellofemoral Pain" on Wednesday, June 1. Coauthors are Rebecca L. Phipps, Ryan E. Cardinal, Peter A. Altenburger, IUPUI.