Effects of Interface Pressure Distribution on Human Sleep Quality
Study by Z. Chen, Y. Li, R. Liu, D. Gao, Q. Chen, Z. Hu and J. Guo
Randomized Crossover Lab Study · PLoS ONE (Vol. 9, Issue 6, e99969) · DOI: 10.1371/journal.pone.0099969
Key Takeaway
Mattresses With Middle-Range Pressure Spread Scored Best for Sleep
What was tested: 16 healthy men slept one night on each of 4 mattresses in a sleep lab, in random order. Researchers mapped body pressure with a 684-sensor mat and recorded sleep with brain wave, eye and muscle sensors (Chen et al., 2014).
What the numbers showed: A hard plank bed packed pressure into a small area, and a pocket spring bed spread it most evenly. The two mattresses in between gave more deep sleep than the plank bed and got higher comfort and sleep quality ratings.
What this means for you: Pressure that was very concentrated or very even both scored worse than a middle range. But the mattresses came from a company that employed several of the authors, and only 16 young men took part.
Key Numbers
How the Study Was Done
The 16 men were 20 to 45 years old with no reported sleep disorders. The 4 mattresses were a plank bed, a palm fiber mattress with a pillow top, a foam rubber and plant fiber mattress with a body-shaped middle layer, and a pocket spring mattress, all bought from DaZiRan Science and Technology Ltd. (Chen et al., 2014).
The authors describe the design as double-blind and randomized, with 2 days between nights. Sleep was recorded overnight with polysomnography, a lab sleep test, and each man rated his sleep the next morning.
What the Study Compared
Two Middle-Range Mattresses (Palm Fiber; Foam and Plant Fiber)
More deep sleep than the plank bed, and higher comfort and sleep quality ratings.
Plank Bed and Pocket Spring Bed
Pressure too concentrated (plank) or spread too evenly (springs). Lower sleep quality ratings.
What the Study Found
Time and share of deep sleep were highest on the foam and plant fiber mattress and lowest on the plank bed. That mattress also had fewer brief awakenings than the plank bed. Total sleep time, time to fall asleep, dream (REM) sleep and the number of turns did not differ between mattresses (Chen et al., 2014).
15 of 16 men called the plank bed hard. 15 of 16 called the palm fiber mattress comfortable, and 14 of 16 said the same of the foam and plant fiber mattress. The authors say the reasons pressure spread affects sleep remain unknown.
The work was funded by the Natural Science Foundation of China. Several authors worked for DaZiRan Science and Technology Ltd., which supplied the mattresses and whose ethics committee approved the study. The authors declared no competing interests (Chen et al., 2014).
An earlier version of this page listed the wrong authors, said 40 people took part, and gave pressure readings and a blood flow threshold that are not in the paper. Those figures and the mattress product picks have been removed.
How to Apply This Study When Choosing a Mattress
What it tells you: In this small study, a mattress that was neither very hard nor very evenly soft gave the best measured sleep.
The study tested 4 mattresses from one Chinese maker, not any brand sold in the U.S., so it cannot tell you which brand or firmness level to buy.
Study Scope and Limitations
16 healthy men aged 20 to 45, one night per mattress, and 4 mattresses supplied by a company that employed several authors. No women, older adults or people with pain took part.
Primary Citation
Chen, Z., Li, Y., Liu, R., Gao, D., Chen, Q., Hu, Z., & Guo, J. (2014). Effects of interface pressure distribution on human sleep quality. PLoS ONE, 9(6), e99969. https://doi.org/