2015 Volume 14 Issue 2 Pages 111-118
The purpose of this study is to evaluate sleep comfort of bed mattresses with different elastic moduli for each body region by measuring physiological and psychological responses. We measured the blood flow of the biceps femoris using near-infrared spectroscopy (NIRS) from the viewpoint of hemodynamics and shape of the back in a supine posture when a person is lying on mattresses with different elastic moduli for each body region. Conventional sleep evaluations were performed to record physiological responses during sleep by polysomnographs (PSG) and actigraphs. Psychological responses during sleep were also evaluated by using the profile of mood states (POMS) test. The results from NIRS revealed that intramuscular metabolic reaction is different according to the sleep posture. Sleep evaluations by PSG and actigraphs showed no significant differences between these mattresses, whereas significant differences were found in the POMS test between some of them. We surmised that difference in hemodynamics is one of the factors in sleep comfort that changes the mood after getting up.