When it comes to your health, there are few absolutes. But that’s not the case with sleep and exercise. You need both, period.
“I couldn’t choose between the two,” says Edward Laskowski, MD, a resident and professor of physical medicine at Mayo Clinic. “Sleep and exercise are like food and water.”
Not only are both necessary, but it’s difficult to get healthy doses of one without the other. “When you look at the research, regular physical activity is important for high-quality sleep, and high-quality sleep is important for physical performance,” says Cheri Mah, a sleep medicine researcher at Stanford University and the University of California, San Francisco.
But when pressed to choose one that’s more important, Mah grudgingly decides on sleep. “Sleep is foundational,” she says. While specific needs vary from person to person, she says most of the scientific literature suggests adults need a minimum of seven hours of good sleep every night. “Lots of individuals think they can operate on less, but when you test them, you find they’re not performing at their best,” Mah says. “They get used to feeling tired, and they think that’s the norm.”
Sleep is the base on which a healthy mind and body stand, she explains. From your immune function to your mood, energy, appetite and dozens of other health variables, if that base is wobbly, your health will suffer.
But let’s assume you’re getting your seven-plus hours every night. Can you sacrifice some sleep a few times a week in order to fit in regular exercise? Yes, but with caveats, says Dr. Phyllis Zee, director of the Center for Circadian and Sleep Medicine at Northwestern University.