Adequate time in bed, regular sleep timing, sufficient physical activity, and appropriate light exposure facilitate optimal sleep stages for memory formation, brain health, and clearing metabolic byproducts.

“The idea is, what's that one phase of sleep that's important? No, they're all important. And one way to facilitate is, again, adequate time, good, regular timing, so you're sleeping always in the same phase, and then having enough physical activity during the day and enough appropriate light exposure.”