Does Broken Sleep Really Matter?
The answer anyone with an overactive bladder, a baby or a lot on their mind needs to hear now.
You went to bed at 11pm and got up at 7am. That's eight hours. Score! But before you revel in feeling like a person who's got their life together, we have to ask: How many times did you wake up throughout the night?
You probably know that each night you go through multiple sleep cycles, which begin with light sleep and progressively get deeper, eventually transitioning into what's called rapid eye movement (REM) sleep—the type that's thought to impact memory and mood. "Most people naturally wake briefly at the end of each sleep cycle", says Brandon Peters, MD, a sleep physician at Virginia Mason Medical Center and adjunct lecturer at Stanford University. Since each sleep cycle lasts 90 to 120 minutes, you'd likely stir for a minute or so three or four times over the course of eight hours. You might just roll over or adjust the covers, and it's normal not to even remember being awake. It's also perfectly normal to wake up if you have to pee (we've all mimed our way to the bathroom in the dark) or if someone (a baby, your snoring bulldog or partner) makes noise.
Over time, broken sleep can cause you to feel less refreshed, more irritable and less able to concentrate the next day.
PhD, Director of Human Sleep Research Program at SRI International
But if in your eight-hour sleep stretch you logged a cumulative 30 minutes of awake time, you've experienced what experts call broken sleep. Not a big deal here and there, but over time it can cause you to feel less refreshed, more irritable and less able to concentrate the next day, says Fiona Baker, PhD, the director of the Human Sleep Research Program at the non-profit institute SRI International.
Weird but true: How solidly you sleep can also make a difference to how sensitive you are to pain, according to a study Baker co-authored in The Journal of Pain. While the exact relationship is still under review—researchers know it has to do with the brain—Baker believes that how broken your sleep is for just one night can likely affect how well you tolerate a rolled ankle on your hike or soreness the day after your WOD. That pain factor, though temporary, could be enough to keep you in or out of the gym, so it's worth keeping a (closed) eye on.
And not to scare you, but in the long run, sleep deprivation of any kind may invite health issues like weight gain and insulin resistance, says Dr Peters, citing a review published in the journal Nature and Science of Sleep. If you're experiencing broken sleep at least three nights per week for at least three months and it interferes with your daily functioning, see a sleep specialist to investigate any underlying issues.
While not every wake-up can be prevented, many can. These are the culprits to look out for and how to avoid them.
1. Your Stress Level
Sometimes you're so beyond mentally, emotionally and/or physically exhausted that you fall asleep with little struggle. But if you wake at the end of a sleep cycle, whatever stressor has you in full-fledged "what if" mode—whether it's the crazy week you have coming up or a family emergency—can ignite your sympathetic nervous system (your fight-or-flight response) and keep you up, explains Baker.
Get it in check: To help your head feel a bit more settled before it hits the pillow, create a to-do list for the next day, or book a yoga class or therapy session (the prospect alone is helpful), suggests Baker.
2. Your Nightcap
You have a drink (or two) before bed and fall asleep no problem, thanks to alcohol's sedative effect. But at 2am, you're wide awake. You might need to pee—but also, your body is finishing up metabolising the alcohol, leading to disrupted shut-eye during the second half of the night, says Baker. Booze also modifies the electrical brain activity that normally happens during sleep and keeps your heart rate up, the opposite of what you want.
Get it in check: Have your drink at least a few hours before bedtime, advises Baker (think happy-hour cocktail versus after-dinner wine).
3. Your Erratic Schedule
When you go to bed and wake up at different times every day, you can throw the regularity of your circadian rhythm, or body clock, off track, agree Baker and Dr Peters. And when your clock is out of sync with the natural patterns of light and darkness, you can bet it's going to tick at weird times throughout the night too, because it's more or less confused as to when you should be conked out and when you shouldn't.
Get it in check: "Try to keep a regular sleep-wake schedule with a fixed wake time, even at weekends", says Dr Peters. And if you can, get 15 to 30 minutes of sunlight when you get out of bed, he adds, which can help your clock get in sync with the day's natural sunrise and sunset rhythm.
4. Your Sleep Environment
"You've got to feel secure, warm and cosy in order to fall—and stay—asleep", says Baker. Creating a relaxing ambiance helps your sympathetic nervous system shut down and remain shut down, even if you briefly awaken during the night, she explains. Then your parasympathetic nervous system (the rest-and-digest one) can take over, helping you fall back asleep more quickly.
Get it in check: Take your TV out of the bedroom (or at the very least, put it on a sleep timer), use earplugs and/or a white-noise machine and wear an eye mask, suggests Baker.
5. Your Lack of Sleepiness
Spending too much time in bed not sleeping is counterproductive. That's because you want your body to associate being in bed with being asleep, explains Dr Peters. "If too much time is spent awake, we may associate the bed with wakefulness or, worse yet, with anxiety and insomnia".
Get it in check: Spend an hour relaxing in your living room (read, journal, breathe slow/deep, do yin or restorative yoga, practise mindfulness, progressively relax your muscles or listen to calming music) to help wind you down before you actually get in the cocoon that is your bed. This allows time for sleepiness to naturally kick in, says Baker.
Even if you follow this advice, you might still struggle with the inevitable 3am wake-up. If that happens, the age-old counting-sheep trick actually works, says Baker, or you can try "daydreaming" in bed: Imagine your happy place as you focus on deep breaths.
Not doing it for you? Get out of bed if you've been lying there for more than 20 minutes (so you don't associate bed with being awake), then try reading, meditating or queuing up a lullaby-like album. Hop back into the sheets only when your eyes are closing. Give it time and trust the process—it'll happen.
Words: Caitlin Carlson
Illustration: Paul Blow
Take It Further
For more expert-backed guidance on sleep, as well as mindset, movement, nutrition and recovery, check out the Nike Training Club App.
Take It Further
For more expert-backed guidance on recovery, as well as mindset, movement, nutrition and sleep, check out the Nike Training Club App.