AUSTIN, Texas—Resistance training can reverse the adverse effects of hormone loss, endurance training helps the heart withstand a heart attack and weight training stops the decrease of blood flow to the legs as one ages, research by three University of Texas at Austin kinesiology professors has revealed.
The findings were announced at the American Physiological Society’s 2004 Intersociety Meeting, titled “The Integrative Biology of Exercise” and held in Austin.
“This meeting represented the cutting edge of science and researchers’ attempts to understand how exercise helps molecules, cells, organs and organisms function properly,” said Dr. Ed Coyle, a professor in the Department of Kinesiology and Health Education. “Our department has an exceptionally strong research group in this area, with six faculty members and 40 graduate students conducting studies on a very wide array of related topics. Our program is a recognized model for the power of integrative biology.”
Dr. Roger Farrar, a faculty member in the Department of Kinesiology and Health Education and a presenter at the conference, has done research on how one can continue to build muscle even as one ages and sees a decrease in particular hormones. Knowing that certain hormones are necessary to build and maintain muscle bulk, Farrar wanted to see what would occur if a subject underwent resistance training and experienced a decrease in the desired hormones.
Experimenting with genetically altered mice, Farrar discovered that if the animals were pushed with resistance training, their muscles adapted and compensated despite a deficit of IGF-I in the blood. Although there was a reduction in the circulating levels of this IGF-I in the blood, resistance training induced the muscle itself to produce IGF-I, and the muscle produced normal increases in mass in response to the resistance-training regimen.
“Most every scientist who was at the conference is looking at the cellular mechanics of what occurs during exercise, the cellular adaptations that occur in skeletal muscle when someone goes through endurance training, resistance training or is inactive,” said Farrar. “If we can discover and understand exactly what happens when we exercise, we can, for example, substitute those changes with a pill or drug that could maybe achieve or enhance these health benefits. This is especially important in members of an aging population that may be mobility impaired.”
Dr. Hiro Tanaka, a kinesiology faculty member and presenter, also has done research related to resistance training and the effects of aging on physical performance. Tanaka conducted studies of young, middle-aged and elderly adults to determine the impact of resistance training on blood flow to the legs.
“Any physical task involves physical expenditure of energy,” said Tanaka. “During exercise, the energy-burning is supported by blood that gets to the tissues. As one gets older, the amount of blood going to the legs decreases and impairs physical performance, but I discovered that regular weight training causes this decrease in blood flow to the legs not to occur. There were clear health benefits to the resistance training.”
Dr. Joe Starnes, a kinesiology faculty member whose area of expertise and interest is cardio-protection, presented results from experiments in which he subjected endurance-trained rats to two different kinds of heart stresses and then examined the effects on the heart.
“A heart attack was one of the two kinds of stresses we tested, and when we simulated a heart attack in a rat that had completed a program of endurance training, the heart held up much better,” said Starnes. “However—and this was unexpected and a big surprise—if the stress was in the form of free radicals in the blood, the exercise-trained heart was actually less resistant than the sedentary heart.”
Free radicals are a by-product of the cellular processes of burning fuel and are potentially harmful to the body.
Dr. Starnes reported that changes in the distribution and quantity of the enzyme nitric oxide synthase within the endurance-trained heart play a role in how it responds to specific stresses. This information is likely to be valuable in the treatment and management of cardiovascular disease, which has an economic impact of $368.4 billion in the United States according to the American Heart Association.
In addition to having Farrar, Tanaka and Starnes present research findings at the intersociety meeting, the Kinesiology and Health Education Department also hosted a reception for all conference attendees. About 200 members went to the reception and were given tours of the department’s labs, as well as the university’s sport facilities.
“Our department is quite well-known among exercise physiologists,” said Farrar, “and many of the scientists were anxious to see our laboratories and talk to us about our research. All in all, this event was a wonderful opportunity for us to show off our work and network with some very distinguished and accomplished researchers. Some of our graduate students were able to meet these scientists, discuss their research and make valuable contacts for research opportunities in the future, and three of our department’s former doctoral students gave talks on how they pursued careers that built upon what they learned here at UT.”
The intersociety meeting, which occurs every four years, drew about 650 renowned scientists and researchers from around the world and represented members of the American Physiological Society, American College of Sports Medicine and Canadian Society for Exercise Physiology.
During the course of the three-day meeting, there were 12 symposia, representing 50 international speakers and papers, as well as 330 volunteered papers presented in poster sessions.
For more information contact: Kay Randall, College of Education, 512-232-3910.
