Forget Sleep Tracking—Try Sleep Hacking
A review of three devices: SleepScore Max, Eight Sleep, and Dreem.
Some nights, radio beams rained down on my chest while I slumbered. Other nights, a pad under the sheets cooked me alive. And then there was the rubber crown on my head that delivered nonsense words into my skull via bone conduction.
Odd as these electronic interventions sound, their lure was irresistible.
I have lots on my mind at night — busy career, catastrophic debt, thriving teenagers, obnoxious teenagers, beautiful but derelict house whose major systems seem to self-destruct by the day. Over the years, no formula has guaranteed sleep. I feel like I’ve exhausted every variable — sleeping alone in the guest room, sleeping cold, exercise, meditation. I’ve done everything short of the advice of my mother-in-law (“I draw a warm bath.” Yes? “I get in bed with the dogs all around me.” OK. “Clean sheets every three days and a warm cup of tea.” Yes? YES? “And then just a chip, just a little corner, of a Darvon.” Ugh, why do I even start these conversations?).
I have tried Fitbits and other wearable trackers, but they don’t capture very accurate data about sleep, and they don’t offer solutions to the problems they help you spot. But this wave of newer trackers promises something radical — to not only gather data, but to actively monkey with your sleep to improve it. They literally get inside your head to manipulate the sleep stages.
Among the three new devices that I tried, SleepScore Max won for ease of use. The Eight Sleep Tracker had some strong points, including the fact that it disappears to the user. As for the strange crown, the Dreem, it has a lot of appeal, too. It probably tracked my heart rate and other metrics better than the others, and offered the most sleep-improving interventions of them all.
I tested each device for two weeks and also spent a few days using all of them at once, to compare the data they collected. By the end of the review, I was sleeping a little more each night, and the data showed that the crucial stages of deep sleep and REM had lengthened slightly. (Deep sleep typically occurs in the first half of the night. REM — that mysterious dream-filled state we share with other mammals and with birds — usually happens after, ideally accounting for 25 percent of total sleep time.)
In the end, I’m not sure whether most of these improvements arose because of the direct influence of the gadgets or because they gave me good data to act on myself. Using these devices made me more aware of indulgences before bed — such as bad TV — whose effects I hadn’t noticed before. But now that I could measure their effect on my sleep, I could see that they mattered.
SleepScore Max ($150)
SleepScore is a bedside tracker whose core technology was developed by ResMed, a large American medical company focused on sleep apnea. The Max bounces low-frequency radio waves off your chest to detect minute differences in your movement and thus derive your respiration rate. Using the rate of breathing, an algorithm generates a profile of your sleep stages. A SleepScore app sounds an alarm to manipulate your wakeup time and maximize your alertness in the morning.
All three of these systems give you a 0-to-100 score for the night, indexed against everyone else’s average. That fueled competitive urges to boost my pathetic 35 minutes of deep sleep.
But SleepScore provided the most eerily personalized advice, telling me I needed to prepare for bed earlier, nagging me to tame my schedule, and finger-wagging about a sedentary day or booze before bedtime. (A recent study from Finland found that two drinks before bed can reduce the restorative quality of sleep by 24 percent.) Every day, I took a little survey through the app to log such damaging behaviors, and this self-reporting seemed to reinforce the lessons I got from the sleep data.
But there’s also a cumbersome aspect to the app — you have to use it to begin the SleepScore’s tracking for the night. I found it counterproductive to begin bedtime that way, trying to avoid temptations of late-night social media. Ideally the tracker would automatically detect when you’re getting into bed (as the Eight tracker does, described below). If so, it might also be able to discern between you and much smaller creatures. One morning, my cat crawled into the warm space I left and promptly fell asleep. The data for that night showed that I slept 10.5 hours with an unusual stretch of deep sleep at the very tail end of my night.
Eight Sleep Tracker ($400–420, depending on size)
The Eight Sleep Tracker is a sensor pad that fits over a mattress and tracks body movement. But the feature I fell in love with didn’t have much to do with sleep cycles at all; it was the integrated heating pad. Heating pads are rife on the market, but this one can be scheduled and controlled through the Eight Sleep app and remotely turned off to save energy if you’re not coming home. While I found the design of the app confusing — thus a few nights of accidental roasting at dawn — the convenience of scheduling a bed warming won me over.
Eight Sleep’s tracking, based on the body’s motion, delivered poor data in comparison to the other products. But its ability to automatically start tracking every night shows much promise. So does its feature that triggers an alarm at the end of your last sleep cycle, so you wake up refreshed. Waking in the middle of a sleep cycle tends to make you groggy. It also has a nifty interface to controllers like Amazon’s Alexa and IFTTT (IF This Then That) to trigger a morning coffee or fire up your Hue lighting system.
The weirdest of these three devices is the Dreem, designed by Yves Béhar and sold by a French startup called Rythm. It’s a rubber thing you strap on your head. It has pulse oximeter sensors to gauge your heart rate and electroencephalogram (EEG) sensors to detect the electrical impulses associated with brain activity and eye movement. Then, when it detects that you’re in deep sleep, the device tries to extend that phase by making “pink noise” in your inner ear. (It does this through bone conduction, presumably not to interrupt your partner’s sleep.) Pink noise sounds like static, but consists of a specific spectrum of random noise that academics have found to stimulate the slow-wave brainwaves that occur during deep sleep, the stage that does wonders to repair the body and may help consolidate memories.
Dreem also has a secondary function, for when you first lie down. You can use an app to have the helmet help put you to sleep: there’s a guided meditation, or the sounds of chirping crickets, or the very strangest option all — a Frenchwoman murmuring nonsense words such as “radiator . . . upstream . . . frying pan . . . mountain top . . . bicycle” directly into your noggin. It works. You stop perseverating about the day’s awkward conference call long enough to wonder what the hell she’s going on about and to cue a sort of Fantasia of swirling radiators and frying pans in your imagination. Next thing you know it’s a one-way trip down River Lethe.
This wave of newer trackers promises something radical. They literally get inside your head to manipulate the sleep stages.
Early in the trial, I’d whip the headgear off as if it were a scratchy shirt or uncomfortable bandage. Two things prevented me from giving up, though. I read that Philips Electronics, the consumer products giant, is launching a similar sleep band this summer, which reflects more credibility on Rythm’s product. And I participated in the Dreem customer service interview, which is offered to every new user. The company set me up on a call with the companionable “Jonathan” who absorbed my complaints about the headgear in stride. “You will get used to it,” he assured. “After 10 days, it will feel part of you.”
He was right; I was soon wearing it long enough to see that the pink noise did something interesting. Now, keep in mind that Dreem doesn’t promise to necessarily lengthen your deep sleep. Instead the company says it can increase the amplitude of the slow waves in your brain, making whatever deep sleep you get more restorative. That’s important because you tend to get less of it over time. While young adults might spend 20 percent of their slumber in deep sleep, that percentage usually declines with age.
In my case, the pink noise appears to have increased the oscillations of slow waves in my deep sleep by as much as 40 percent. Whether that alone is restorative is hard to know; the Dreem also appeared to slightly lengthen the duration of my deep sleep stage, according to data not only from the Dreem but from the other devices I had on hand for this review.
Dreem was also the only device that accurately tracked my heart rate. Because I was finally getting back in shape after a dormant winter, the pulse-oximeter feature was worth the break-in period alone. I got to see my resting heart rate drop by two beats per minute over the course of the review, showing that I was getting fitter and not overtraining. Such heart-rate accuracy is usually only possible by wearing a chest strap. (SleepScore also tracked beats per minute, but was inconsistent and typically off by over 10 beats.)
The crown-like design of the Dreem somehow vindicates little Ralph Wiggum’s belief: “Oh, sleep. That’s where I’m a Viking.” But for all the futuristic elegance in Béhar’s design, the headgear seemed most useful for birth control.
Nonetheless, I find myself reaching for the rubber sleep helmet to get better rest. My partner still won’t go near me, but I’m slumbering well on nights when I need to recharge. I like checking in with the Frenchwoman’s terrible poetry — “motorboat . . . Chamonix . . . solar cream.” (What the hell even is solar cream?) Who knows? Maybe sleep really is when I’m a Viking.
This story was updated on June 12, 2018, to delete an incorrect reference to Nintendo’s role in SleepScore. The technology in the device did not grow out of ResMed’s collaboration with Nintendo.