Study Finds Method to Bulk Up Muscle During Bed Rest

People go to the hospital to get well, but with long visits come risks. Among them is muscle wasting caused by days, or weeks, spent lying down and sitting. The average patient bounces back over time but for weaker individuals, particularly the frail elderly, extended inactivity can be a tipping point that leads to a spiraling decline in health.

A new study led by Micah Drummond, Ph.D., assistant professor of physical therapy at University of Utah College of Health, has found a way to keep muscles from deteriorating during bed rest. A combination of supplementing diet with extra protein, and electrically stimulating the tissue with a device commonly used in physical therapy, halted the damage.

Study participants who did not receive the two treatments lost four percent - or nearly one pound - of leg muscle. By contrast, the newly developed regimen prevented muscle loss. The results were published in the journal, Rejuvenation Research.

Volunteers, healthy men and women between the ages of 60 to 80, spent five days in the Center for Clinical and Translational Science Clinical Services Core facility. During that time they lay in bed for most of the day, and CCTS nursing staff helped them with needs requiring them to get up, including trips to the bathroom.

Half of the volunteers received the two interventions, each based on a scientific understanding of how muscles work. Previous research has shown that both an influx of protein and muscle contractions cause cells to build more proteins, a step critical for maintaining muscle.

Drummond’s team jump started the physiological process by having participants consume a customized protein drink and administering mild electric shocks to major muscle groups in the thigh three times each day. The latter was performed by neuromuscular electrical stimulators: inexpensive cuffs that transmit carefully controlled electrical impulses to an arm or leg.

The one-two punch made a noticeable impact. “You could see the difference,” remarked Drummond. “Participants that didn’t undergo the therapy definitely had smaller thighs.”

There were changes at the cellular level, too. The interventions blocked signs of muscular atrophy, including MAFbx, a molecule involved in protein breakdown, and Myostatin, an inhibitor of muscle growth.

Counterintuitively, even though treatment boosted muscle mass, muscle strength still declined. “If we could find a way to preserve both muscle mass and function, then that would help some patients immensely,” explains Drummond.

Retaining mass alone could have its own benefits. In addition to providing movement and might, muscles perform other functions such as helping keep blood sugar levels in check. Drummond will explore those potential benefits in continuing investigations. He will also search for the key to retaining muscle function.

“It could be that there is no substitute for some form of resistance exercise,” he says. “We may need to supplement with old-fashioned squats at the bed side in order to maintain muscle strength.”