@article{Torobrum_2017, title={The Influence of Density of the Materials and Body Mass Index on the Elderly’s Sleep Efficiency}, volume={7}, url={https://ojs.imeti.org/index.php/PETI/article/view/948}, abstractNote={<p>Insomnia is a common problem among the elders and it directly affects their health. The mattress is one factors influencing sleeping efficiency. The developed pressure at the sleeping surface during sleeping will to cause body discomfort, leading to sleep problem. The developed pressure depends on the density of bedding materials and body mass. The present research aims to study the effects of the mattress density and body mass on the elderly sleep efficiency. The sleep data was collected from 6 volunteers: 3 male and 3 female at the age group of 60 – 79 years. The experiment was done on mattresses with densities of 24.6 and 60 kg/m<sup>3</sup> and 4-inch thickness. The volunteers randomly slept on each mattress for three nights. Sleep data was recorded by sleep tracker (Jawbone up24), calibrated with Polysomnography. The study revealed that sleep efficiency on the 60 kg/m<sup>3</sup> density mattress was more than 90 percent while those on the 24.6 kg/m<sup>3</sup> density mattress were in the range of 78-84 percent. Moreover, sleep efficiency of the volunteers with the body mass index of 22.22 - 23.74 kg/cm<sup>2</sup> was significantly different from those of volunteers with the body mass index of 24.61-24.92 kg/cm<sup>2</sup> when they slept on the 24.6 kg/m<sup>3</sup> density mattress. Additionally, the pressure test revealed that a pressure at shoulder may affect sleep efficiency.</p>}, journal={Proceedings of Engineering and Technology Innovation}, author={Torobrum, Wichan}, year={2017}, month={Dec.}, pages={08–13} }