Study Seeks to Learn More About Muscle Control

A researcher from the University of Delaware is looking into what exactly causes the decline in muscle control in older people with the ultimate goal of improving movement in the elderly and those with neurological disorders such as cerebral palsy.

The Problem

As people age, the neurons that convey commands from your brains to your muscles start to struggle a bit. They have to “speak” more loudly to get the muscles to act, according to Christopher Knight, UD Researcher and assistant professor at the UD College of Health Sciences.

“As a result of age-related changes in muscle and neurons, elderly people are often frustrated by poor control during precision tasks, and slowed physical responses contribute to more falls as people grow older,” said Knight.

More Study

Knight and his co-author Gary Kamen, director of the Exercise Neuroscience Laboratory at the University of Massachusetts, recently published the results of a study examining motor-unit firing rates in the Journal of Applied Physiology. Knight is now beginning a new study on motor control in the elderly.

“Muscles are the driving force behind our movements,” said Knight. “Every time they get a command from the neurons, the muscle fibers contract. In the generation of muscular force, the smallest controllable unit consists of an individual neuron and the muscle fibers it stimulates.

“We believe that our research is very important to our understanding of motor-control mechanisms in general and impaired control in patient populations.

Results

The study found lower neuron firing rates among the elderly than younger subjects, which roughly translates into a diminished ability of the muscles to respond to neuron commands, such as in movement disorders.

“The repeated contraction of muscles is essential to movements such as walking,” said Knight. “However, our muscles have a reduced capacity to contract or ‘twitch’ as we grow older. We lose fast-twitch muscle fibers as we age.”

Knight said we can already take steps to improve neuron firing rates. “After power training with weights, we see an increase in firing rates … For safety, we’re commonly advised to do things slowly when exercising, but it’s important to also do some fast exercises. You need a fast movement to prevent a fall.”

If your child or someone you know suffers from cerebral palsy, contact a cerebral palsy attorney who can help explain the rights of cerebral palsy patients.