When was the last time you got out of bed and felt rested and ready to take on the day? Is it news to you that such a feeling is possible?
Sleep is absolutely crucial to our physical and mental health — so much so that a long-term shortage of it can increase your risk for cardiovascular disease and shorten your life expectancy. If I were to ask you how you slept last night, your first criteria for judging that would probably be how long you slept. I’m here to tell you that isn’t the full story.
Drawing from one of my fellow students’ sleep data, I created this infographic illustrating the inexact, fickle nature of human sleep. If you’re looking to get more out of your time in bed, upping the quantity of your sleep won’t help you much. Only establishing a consistent, predictable rhythm of sleep will keep you feeling rested.
I plotted out my subject’s sleep and wake times in the first graph below — they varied widely from the median from night to night. It’s no wonder that the subject’s stress levels were higher on nights when she deviated farthest from her sleep schedule: sleep quality hinges less on the length of your sleep and moreso on its consistency with natural indicators.
Our bodies’ circadian rhythms are influenced by a set of biological signals called zeitgebers — these include light exposure, body temperature, exercise, caloric intake, and even social interactions. Managing these carefully is critical to getting decent sleep.
The most important zeitgeber is light: your body expects to wake up alongside the sunrise and fall asleep a couple of hours after sunset. Going to bed too long after dark or waking up too long after the sun rises can throw off your day from the start. Exposure to the unnatural blue glow of a phone screen can disrupt your circadian rhythm too, especially if that exposure happens in the middle of the night.
Still, even natural rhythms don’t tell the full story of human sleep. Practicing good sleep hygiene is the final piece to effective sleep regulation. Sleep hygiene is an overarching psychological concept governing sleep that deals with separating our sleep from the rest of our lives. That looks different for each of us as individuals, but using your bed only for sleep is a great way to start — that means no homework, no phone, and no eating between the sheets.