Strong daytime light exposure, especially in the morning, increases circadian amplitude, leading to improved nighttime sleep.

“The second thing that it does is that it creates a circadian amplitude. So your circadian rhythm, this 24-hour cycle, it's like when you're on the couch in the dark all day, you don't have a strong daytime rhythm. So you don't have a strong nighttime rhythm. But if you get a strong daytime signal by being active and and getting especially outside light, especially in the morning to start that curve going, by the time nighttime comes, you'll have an even stronger nighttime signal.”