To evaluate the effects of comfort in a hypnagogic posture on sleep feelings estimated by standardized OSA sleep inventory MA version and sleep quality measured by actigraph, eighteen healthy subjects (8 males, 10 females), aged 61-65, were recorded, sleeping in their homes for 15 consecutive nights under two crossover designed conditions from Friday. A subject slept for 7 consecutive nights (4 adaptation nights and 3 nights for analysis) on a relatively comfortable mattress first and then for 8 consecutive nights (4 adaptation nights, 3 nights for analysis and excluded last night) on a relatively uncomfortable mattress. The results showed the sleep on a relatively comfortable mattress indicated better sleep quality and feelings.
