Study Uncovers the Truth About “Sleeping Positions”
There are almost countless sleeping positions. There’s side, stomach, back, log, starfish, free fall, covered in crumbs, and more.
The truth is no one really has one. We might like to think of ourselves as side sleepers or back sleepers, but a more accurate descriptor, for all of us, is: all-over-the-place sleepers. We found this out after doing a camera study on sleeping positions during development for the Casper pillow. The positions most people fall asleep in are different than the ones they end up in, and the positions they do end up in are the goofy types that they never recall.
Having “a sleeping position” mostly just refers to how we prefer to fall asleep. When we asked participants during the study about how they slept, they usually identified a clear type, like side or stomach. We saw that that didn’t hold up. People would fall asleep on their stomach and then roll over onto their side, grab a pillow and put it between their knees, and so on. For example, 70% of participants slept on their side at some point during the night, no matter what position or positions they had identified. The reality is that sleeping is more activity than rest.
Most pillows aren’t constructed for how we really sleep. Most pillows are optimized for a particular position. They’re filled with foam or fiber, to achieve a certain height, shape, or density. The problem is that at some point during the night they become the worst pillow for how you’re actually sleeping. The reason, in part, is that it’s hard to find a material or filling amount that makes a pillow work for anyone in any position.
I spent a lot of time looking for a pillow filling that would allow it to be nearly universal. We conducted a survey of all the different pillow fillings on the market. One option we considered early on was memory foam, it adapts to weight and shape, but we quickly found it wouldn’t be best for the pillow we were trying to create. Memory foam can sleep hot — we needed something that sleeps cool — and a lot of people complained that memory foam pillows don’t have the huggable, squishable feel that they love, so we moved beyond it.
We dove into the material sciences. We visited a fiber guru (yes, there is such a thing), and went to almost a dozen other experts around the U.S. We learned that synthetic fibers can have wildly different properties, depending on their polymers and finishings, and there are thousands of varieties. The next step has been the key.
We started looking for a fiber with the softness of down and rebound of foam. I gathered together fibers from our trip all over the world and emptied them into bins to dissect them and build prototypes. We ran our hands through them: some of the fibers felt waxy or dry, some stuck to your clothes, and others quickly fell to the ground. We used a leaf blower to fill trial pillows with different fibers and handed the prototypes out for testing. Through all of that, there was one pillow we made — out of one unique microfiber — that people universally loved and was perfectly squeezable and adaptable.
The fiber itself is probably the secret ingredient to the Casper pillow. It’s a synthetic blown fiber with a special polymer and coating, and it’s incredibly thin (its width can be measured in atoms). We created prototypes with different amounts of the fiber inside and had over 90 members of Casper Labs, of varying ages, genders, and weights, test them out. The fill amount we settled on equates to one billion fibers in each pillow.
It was the perfect amount of fill, and perfect fiber, to create the pillow we were looking for: one with the softness and comfort of down and the conforming qualities and rebound of foam. You can see how it came out here.
Carly is the former VP of Product Dev. at Casper. Previously she worked at IDEO and Smart Design where her work was recognized with multiple design awards.