When it doesn’t pay to stay in bed

Many medical conditions, including high-risk pregnancies, congestive heart failure and surgical procedures, send people to bed for prolonged periods. Some nursing home patients virtually live in bed. And people with chronic fatigue syndrome or fibromyalgia sometimes put themselves to bed for long periods.

But prolonged bed rest can be a medical disaster.

Human bodies evolved in sync with Earth’s gravitational pull. Without that force to pull against, muscles and bones get weak with stunning rapidity as the rate of muscle protein synthesis drops.

“If you’re healthy, you can tolerate a week without trouble, but after that, you start to see large losses of muscles and bone,” says Dr. Ronenn Roubenoff, an associate professor of medicine and nutrition at Tufts University.

Roubenoff is trying to document how debilitating bed rest is for muscles and bones. He’ll be leading a study of 50 healthy men, ages 30 to 55, who will be paid $5,000 each to spend 28 days in bed, just lolling around, not even allowed to get up to go to the bathroom.

The unusual study, to be done at Tufts-New England Medical Center in Boston, also is designed to see whether resistance training with springs and pulleys, along with special protein supplements, can reverse this downward slide.

Among other things, bed rest triggers inflammatory cytokines, natural chemicals such as TNF, IL-1 and IL-6, that tell muscles to export amino acids to the liver so the body can make the antibodies and white blood cells to fight disease.

“We are built to sacrifice protein from muscle, in times of stress, to boost the immune system,” says Roubenoff. “We’re designed to get better relatively quickly or drop dead.”

Cytokines are the reason people feel lousy when they get the flu, says Dr. Jeremy Walston, a geriatrician at Johns Hopkins Bayview Medical Center in Baltimore.

“People feel malaise and weakness. That’s due to the impact [of cytokines] on muscle.”

Without the pull of gravity, a growth factor called IGF-1 is markedly reduced, further weakening muscles. Calcium leaches out of bones, winding up in the kidneys, where it can cause kidney stones.

Bed rest also leads to bedsores, which in turn can lead to deadly infections. Circulation in the legs slows too, potentially triggering blood clots. Inactivity triggers constipation as well.

Moreover, it takes only a few days of bed rest to cause insulin resistance, which can lead to diabetes, says Bob Wolfe, a professor of surgery at the University of Texas Medical Branch in Galveston.

Lung function deteriorates with prolonged rest too, says Dr. Michael Keane, director of the intensive care unit at the David Geffen School of Medicine at UCLA.

For these reasons, hospitals insist that patients get up and move around, even after major surgery.

In the landmark Dallas Bed Rest and Training Study, researchers put five healthy college men to bed for three weeks in 1966 and measured their muscle loss and other factors. When allowed to get up and exercise again, the men recovered.

Thirty years later, the researchers tested the same men again. The results were stunning: The three weeks of bed rest the men had experienced in their 20s “had a more profound effect on physical work capacity than did three decades of aging.”

And it’s not just sick people who spend long periods in bed.

Dr. Alan De Cherney, professor of obstetrics and gynecology at the Geffen School of Medicine, says that some women with high-risk pregnancies are put to bed for as long as 20 weeks.

Bed rest is often prescribed for women carrying triplets, those with a weak cervix, those in premature labor and those with bleeding problems. “The theory is that if you stay off your feet, there is less pressure on the cervix, so you’re less likely to deliver,” De Cherney says. “I have no idea if it’s effective.

“But I wouldn’t take a chance, so I would prescribe it if [a pregnancy] is too high risk.”

The good news is that a little judicious exercise in bed can minimize the dangers.

Dr. Christopher Cooper, an exercise physiologist at Geffen, says data show that even frail geriatric patients can exercise in bed, lowering the risk of incontinence. (This often occurs in people who get so weak from bed rest that they can’t get out of bed.)

You have to use common sense, of course. Don’t exercise in bed if you have a fever. But you can try to sit up several times a day.