but you won’t reach peak fitness if your sleep quality isn’t an eight out of 10,” Mr. Sorensen said. “This is when our body recovers.” Jen Murphy is a freelance writer based in Boulder ...

Jen Murphy is a freelance journalist who splits her time between Colorado and Maui. She writes the Wall Street Journal's "What's Your Workout" column and is the author of “The Yoga (Man)ual.” An ...