After crunching the numbers, the team found that the average Biobank participant spent a median of 2.5 hours of time outdoors daily. The kicker was that for every extra hour spent outside, participants reported better sleep. They tended to have an easier time waking up, more alertness throughout the day, and fewer issues falling asleep and staying asleep.
This shows just how much the light and sleep-wake cycles are connected. “Sleep and light are intricately linked. You can change your light cycle by changing your sleep cycle, and vice versa,” Steven Lockley, Ph.D., a neuroscientist at Brigham & Women’s Hospital and associate professor of medicine at Harvard Medical School, recently told mbg. For example, basking in light during the day tells the brain that it needs to be awake and alert. But once we close our eyes for bed, we shut off light from the brain, sending the signal that it’s time for sleep.