Research Sheds New Light On How "Abs" Function

WHEN IT COMES TO ABDOMINAL MUSCLES, NOT ALL FIBERS ARE CREATED EQUAL, UB RESEARCH REVEALS
Discovery will lead to new strategies for muscle rehabilitation and strengthening

CINCINNATI - Physical therapy researchers at the University at Buffalo have shown for the first time that abdominal-muscle fibers have a specific division of labor, with different fibers answering the call to action, depending on the task.

The findings in this preliminary study shed new light on how the abdominal muscles function during breathing and other tasks, and point to the need for new therapies that enlist the appropriate specific muscle fibers for maximum rehabilitation.

"We used to think that all abdominal-muscle fibers played an equal role in all tasks the abdominals perform, such as moving and breathing," said Frank J. Cerny, Ph.D., UB associate professor of physical therapy and exercise science and lead author on the study. "Knowing that sit-ups strengthen the abdominals, we may have recommended sit-ups as a therapy to improve breathing capability.

"Now we know that doing sit-ups is not going to help with breathing, but a therapy such as breathing against resistance would. We know that with abdominal muscles, therapy must be very specific to the task, because few muscle fibers perform multiple tasks."

Cerny presented the results of the study here today (May 30, 1996) at the annual meeting of the American College of Sports Medicine.

Cerny and colleagues arrived at their findings by inserting wires directly into the abdominal muscles of three subjects and analyzed the activity of single motor units within the internal oblique and transversus abdominis muscles during three activities.

The findings likely are specific to abdominal muscles, Cerny said, because abdominals are used for the essential task of breathing and experience different demands than other muscles in the body. Researchers have tried to determine if fibers of other muscles are task-dependent, with varied results, he said.

Using the results of this study, UB researchers will measure abdominal-muscle activity in a larger group of people, and begin work on refining muscle rehabilitation therapies to fit the specific task.

Also participating in the research were Threethambal Puckree, UB doctoral candidate in exercise science who has since received the degree, and Beverly Bishop, Ph.D., UB Distinguished Teaching Professor of physiology.