Abstract
The selection of a bedding system has direct relationship with sleeping quality. Putting a mattress topper on bed in use is also a common practice to increase sleeping comfort. Thus, the ergonomic study of a mattress topper is an important issue.Forty healthy male subjects were recruited in this study. The experiment involves a combination of 3 different firmness (firm, medium, soft) and 4 thickness (3, 5, 7, 10 cm) levels. For each subject, pressure distribution, temperature distribution, microclimate, electromyography, spinal posture, accompany with subjective ratings were collected to determine the optimal firmness and thickness mattress topper combination.The results showed that the firm mattress toppers had higher pressure in every position. The medium ones also had higher temperatures and it had an increasing trend with time. The microclimate temperature was higher on medium and soft toppers, and it was also proportional to time. But the microclimate humidity was inversely proportional to time. The electromyography of trapezius was lower on soft ones, and the EMG of biceps femoris was lower on firm ones. The slope of spine was lowest on firm ones at T1-T4, T4-T6 and T6-T8. The thick mattress toppers had higher temperatures. The humidity was the lowest at 5 cm, and the slope of spine was smallest at 3 cm. Subjective ratings revealed that the firm mattress toppers were perceived as the firmest and most supportive, while the soft ones had the greatest conformity. Finally, among all 12 combinations, 3 or 7 cm soft and 3 cm medium mattress toppers showed better performance in most physiological indexes, and was considered as the preferred combinations.