GENETICS MAY PLAY ROLE IN EFFECTIVENESS OF EXERCISE

The way people respond to exercise varies widely within the general population. However, within family members, such differences in responses are less dramatic. These observations have lead researchers to believe that genetics plays a role in the effect that exercise can have on the individual

PORTLAND, ME--The way people respond to exercise varies widely within the general population. However, within family members, such differences in responses are less dramatic. These observations have lead researchers to believe that genetics plays a role in the effect that exercise can have on the individual.

Tuomo Rankinen, Ph.D. is an instructor in the Human Genomics Laboratory at Pennington Biomedical Research Center in Baton Rough, LA. Dr. Rankinen will summarize the current knowledge of the role that genetic factors can play in exercise, and will discuss familial blood pressure responses to endurance training during the American Physiological Society’s intersociety meeting, being held September 20-23, 2000 in Portland, ME.

Background: The HERITAGE Family Study (Health, Risk Factors, Exercise Training and Genetics) is the first family-based exercise study ever undertaken. The project began in l992 after earlier research pointed to evidence that some individuals who exercise only lose weight while  others who exercise not only lose weight but improve their heart rates and gain additional benefits that lead to a reduction in risk for certain conditions (e.g., diabetes and cardiovascular disease). 

Since the HERITAGE study began, 750 subjects from 200 families have been studied in five centers throughout the US and Canada. The families are nearly identically split: 99 are of Caucasian descent and 101 are of African descent. More than 70 articles dealing with research gleaned from the HERITAGE group have been published to date.

About the Study: Participants in the study being discussed by Dr. Rankinen underwent 20 weeks of identical bicycle ergometer training in a strictly supervised environment. The participants were evaluated during both pre- and post-training on such factors as oxygen consumption, heart rate, blood pressure, certain respiratory factors, as well as cardiovascular and diabetes risk factors. During Phase Two of the study the researchers are combining the health statistics with the genetic data gathered from blood samples of each volunteer.

Dr. Rankinen and his colleagues have observed that people who exercise can be categorized as either “high-“ or “low-“ responders. While everyone responds to exercise in some way, no one responds in the same way and to the same degree.. The indications are, however, that members of the same family respond to exercise in a similar manner. Genetic factors may be responsible, but shared environmental influences may also play a role.

According to Rankinen, there are individuals who gain benefits from exercise more easily than others do. His research focuses on what causes one person to reap significant benefits while another does not.  With that understanding will come training programs and devices that are tailored to meet each individual’s unique needs.

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Exercise physiology research seeks to understand biological processes that underlie human performance in order to develop exercise strategies can be tailored to improve health and fitness for everyone. Understanding how exercise contributes to improved health is particularly important because many Americans fail to exercise regularly, which contributes to rising incidences of conditions such as heart disease, diabetes, certain cancers, obesity, muscle wasting, and osteoporosis. Exercise physiology has shown that exercise is beneficial and can be safely undertaken not just by healthy people and Olympic athletes, but also by many special populations, such as the frail elderly and individuals suffering from chronic and debilitating conditions. Exercise physiologists examine biological questions with broad implications, such as how muscles adapt to exercise and how cells sense and respond to increased energy needs. Exercise physiology research on human performance has shown that athletes should be well-hydrated when they complete and should seek frequent fluid replacement during endurance events. Athletes in long-distance events should drink fluids with a fixed concentration of glucose, should be acclimatized to heat before competition and are likely to perform better when competitions are scheduled in the early or late hours of the day. Exercise physiology research has proven the advantages to athletes -- particularly swimmers -- of tapering their training before competition and has shown that following specific power and strength training principles enhances performance. Exercise physiology research has also demonstrated that women are physiologically capable of running the marathon without detriment to their health and well being. The American Physiological Society is devoted to fostering scientific research, education, and the dissemination of scientific information about how the body and its organ systems function. By providing a spectrum of physiological information, the Society plays a significant role in the progress of science and the advancement of knowledge.

Editor’s Note: For further information, or to schedule an interview with Dr. Rankinen, contact Donna Krupa at 703.527.7257; cell: 703.967.2751; or at djkrupa1@aol.com. Or log on to the APS website for further information.