Empowering seniors: researchers seek to increase strength and mobility in the elderly

American Fitness, Nov-Dec, 2003

As they grow older, many people find tasks they used to take for granted, such as putting groceries away or lifting their grandchildren, become increasingly difficult due to aging muscles losing their ability to generate power and force. A group of University of Michigan researchers aims to reverse this trend by investigating ways to boost muscle power and speed of movement in the elderly. The project is funded in part by a three-year, $3.8 million grant from Michigan's Life Sciences Corridor.

Headed by Bruce Carlson, director of the U-M Institute of Gerontology and professor of cell and developmental biology, the team is using muscle biopsies to examine muscle fibers at the molecular level and implementing instrumentation to measure weight-training success in participants. A group of 96 subjects, ranging in age from the 20s to over 70, began training this spring.

While weight training is known to increase muscle strength, scientists are seeking a better understanding of the process by using new methods to analyze the biological changes weight training elicits. Ultimately, analysis at the cellular level should provide insight into the most effective strategies to maintain and restore strength as well as increase speed of movement. Speed of movement is as important as strength because faster movement can help prevent certain types of falls among the elderly, Carlson explains.

This study is unique because, in contrast to most studies on aging muscle, the training techniques focus on increasing both strength and speed of movement. Also, training results are recorded at levels ranging from whole body measures to single muscle fiber fragments' ability to contract. Since strength and speed improvements involve not only muscles, but also how the brain communicates with them, the exercise studies' analysis should include how the whole body functions, Carlson says.

Researchers are conducting two types of weight training over a 12-week period--one designed to build strength, the other to improve both strength and speed of movement. Before and after the training period, researchers take thigh muscle biopsies to analyze strength and other characteristics of the muscle fiber. A key question is what kind of approach best builds strength and speed. Nell Cole, president of Bio-Logic Engineering, which makes instrumentation to measure muscle power, is collaborating with the team to help answer that question. Researchers hope to build exercise programs that reduce the likelihood of falling and promote overall physical well-being and quality of life. Many people in the aging field believe exercise is the key to better health and a more active lifestyle as people age.

Researchers from across U-M's campus, each bringing a different expertise and approach, are collaborating on the project. For example, Jeffrey Horowitz and Nell Alexander study how to make people stronger, while James Ashton-Miller studies people's gaits and the factors that lead to falling as they age. Paul Cederna, a plastic surgeon, takes samples of muscle fibers and gives them to John Faulkner, a physiologist who analyzes them at the individual fiber level. Researchers are still seeking participants. If you are interested in participating, contact Linda Nyquist at (734) 936-6078. For more information on the study, contact Colleen Newvine at (734) 647-4411 or cnewvine@umich.edu.

Reprinted by kind permission of the University of Michigan.