Day sleep is better than night sleep for many people and it can even help with studying. In a study, researchers simulated a night shift on study participants and found that when they slept 5.6 hours during the day, they increased extra sleep and kept study participants alert throughout the day. This suggests that day-night schedules are beneficial for those who need to stay awake during the night hours. Additionally, the study found that burning calories when sleeping during the day was more beneficial than sleeping at night. This suggests that rotating shift workers may benefit from day-sleep instead of having to stay awake all night long. A separate study also discovered that altering schedule days resulted in decreased FGF19 levels which mimic circadian disruptions commonly experienced by rotating shift workers or recurrent jet lag sufferers.