First, let’s get technical for a minute: Sleep latency is the scientific term for the length of time it takes you to fall asleep. Different people fall asleep in different amounts of time, but a normal sleep latency generally hovers between 10 and 20 minutes. It’s a simple yet highly underrated metric - because it can reflect a person’s overall rest, recovery and provide deeper insight into overall sleep quality.
It goes without saying, but you definitely want a short sleep latency. The quicker you fall asleep, the sooner your first non-rapid eye movement (NREM) sleep cycle starts. That leads to shorter periods of rapid eye movement (REM) sleep, and then the cycle starts over again. Typically, REM sleep happens 90 minutes after you fall asleep. This is the deepest and most restorative stage of sleep. It’s also where all the good stuff happens - your muscles are repaired, your immune system is given a much-needed boost, and your brain files away important memories, along with a few other seemingly magical bodily benefits.
If you’re tossing and turning, unable to cash in on a quick sleep latency, your body suffers and REM sleep is hard to come by. You wake up feeling groggy and you’re dragging for the rest of the day. But, then again, falling asleep too quickly can backfire as well. “Sleep debt,” is a common problem, and according to Dr. Anis Rehman, an endocrinologist with the Sleep Foundation, the problem is cumulative: “Going to sleep just 30 or 60 minutes later than usual for a few days can quickly add up.”
We’ve all experienced this after a long week at work or at the end of an international flight. You’re so tired, you fall asleep as soon as your head hits the pillow. Your body, in a way, does try to catch up on sleep by kickstarting a process known as REM rebound. Of course, this isn’t sustainable and can mess up your normal sleep latency. Experts recommend staying relaxed and sticking to a regular, predictable bedtime as much as possible.
Fitness values consistency but it’s a discipline that rewards you for changing things up and pushing yourself. The key with sleep is to do the opposite - the less change and more predictability, the better. When you look at your sleep metrics, the results better be boring.
So how can you ensure you master your sleep latency? Make sure that you’re falling asleep within 20 minutes of laying down. Get yourself to a respectable and reliable latency, and then keep it there, despite any and all obstacles that get thrown at you - be it work, personal or live sporting events. The upside is that your commitment to quality sleep will be rewarded with improvements in a myriad of other bodily metrics, from improved respiratory rate and heart rate variability to sharper reflexes and cognitive function.
If you need some ways to fall asleep faster, start by kicking the covers off the end of the bed and keep one or both feet outside of your top sheet or blanket. Sleep researchers know that right before you fall asleep, your body temperature starts to drop. And in the deepest stages of sleep, your body’s at its coolest - about one or two degrees below normal - so this just jump starts the process. Alcohol can help you relax and fall asleep faster, but it’s not recommended because the body has to work overtime to break it down while you sleep. This erases the benefits of a speedy sleep latency, and often delays REM sleep cycles.
You’re better off eliminating any and all light from your bedroom. That’s because light is a powerful cue that sends wake-up signals to the brain, suppressing the production of the sleep-inducing hormone melatonin and making it harder to fall (and stay) asleep. Sleep docs suggest surveying your room for sources of artificial light, from outside street lamps to the glow of power buttons from electronics and eliminating your viewing access to them.
And if you want to really get a handle on your sleep, track it. An Apple Watch, Whoop strap or Oura ring will provide reliable data and detailed metrics on your sleep latency.
*FYI: Whoop has put together a list of 28 simple tactics to help you fall asleep faster.