Should you exercise when sleep deprived? Experts weigh in

Editor’s Note: Seek advice from a health care provider if you have chronic sleep loss and also prior to starting a workout program.

CNN
 — 

It’s the end of another long day at the office after a poor night’s sleep. As usual, you’re exhausted, yet you want to stop at the gym on the way home to get the exercise you need to stay healthy.

Should you work out when you are suffering from chronic sleep loss?

This conundrum is a widespread problem, considering 1 in 3 Americans are sleep deprived, according to the US Centers for Disease Control and Prevention.

“It is definitely a bidirectional relationship, not one or the other,” said Dr. Phyllis Zee, director of the Center for Circadian and Sleep Medicine at Northwestern University’s Feinberg School of Medicine in Chicago.

“First, there is clear data to show that regular exercise improves sleep quality — moderate exercise in the morning, afternoon or very early evening can improve deep sleep,” Zee said.

Deep sleep is the healing stage in which your body repairs and restores itself. Also called “slow wave” sleep, it can only be achieved if your sleep quality is good, with few to no nighttime interruptions.

“Research also shows that if you sleep better, you’re more likely to be able to engage in exercise and your physical activity levels are going to be higher,” Zee said.

“So I would say that even if you have had a bad night’s sleep, you should maintain your physical activity.”

To be healthy, the body needs to move through four stages of sleep several times each night. During the first and second stages, the body starts to decrease its rhythms. Doing so prepares us for the third stage — a deep, slow-wave sleep where the body is literally restoring itself on a cellular level, fixing damage from the day’s wear and tear and consolidating memories into long-term storage.

Rapid eye movement sleep, called REM, is the final stage in which we dream. Studies have shown that missing REM sleep may lead to memory deficit and poor cognitive outcomes as well as heart and other chronic diseases and an early death.

On the flip side, years of research has found sleep, especially the deepest, most healing kind, boosts immune functioning.

Since each sleep cycle is roughly 90 minutes long, most adults need seven to eight hours of relatively uninterrupted slumber to achieve restorative sleep and be healthy, according to the CDC. Sleep debt, along with irregular sleep duration, has been linked to an increased risk of obesity, heart disease, dementia and mood disorders such as anxiety and depression.

One night of poor sleep shouldn’t have to impact your workout routine, but chronic sleep deprivation leading to multiple days of exhaustion is another matter, experts say.

It may not be wise to hit the gym or play a sport when you’re barely putting one foot in front of the other, said sleep specialist Dr. Raj Dasgupta, an associate professor of clinical medicine at the University of Southern California’s Keck School of Medicine.

“Without sleep, your muscles can’t recover from the stress you put them through during workouts. It doesn’t do you much good to keep breaking down your muscles without giving them time to recover and grow stronger,” Dasgupta said.

In addition, you’re more likely to suffer an injury when you’re exhausted, he explained, due to slowed reaction times from your tired brain working to make decisions during the workout or sport.

“Poor sleep can also affect your motivation to exercise in the first place. You might find yourself dreading your normal workouts and hating every minute in the gym, which is not good for long-term adherence to a fitness plan,” Dasgupta said.

In addition, sleep deprivation can lead you to make poor food choices, which affect your fitness and physical performance, he said.

So it’s not a good idea to work out while extremely tired, but you will also sleep better and get more out of exercise if you do. What’s the answer?

Use common sense, Zee said. “If you’re not sleeping well, don’t go for that intense workout, right? Walk or do yoga instead, but certainly maintain an exercise or physical activity regimen at the regular time of the day that you normally would be doing it.”

If you’re pressed for time, consider fitting in several short bouts of exercise throughout your day.

“Everything counts,” Dasgupta said. “Do anything that makes you feel happy and refreshed. This is about hitting the reset button for yourself, not doing some form of exercise because you feel obligated to.”