Investigating the Impact of Long-Term Use on Mattress Firmness and Sleep Quality—Preliminary Results

Mattress comfort, often associated with firmness, is a complex construct influenced by factors such as material composition, construction, and personal preference. In this short communication paper, we indirectly investigated the effects of long-term mattress use on its hardness and sleep quality by observing the changes in the mattress. A mechanical durability test was performed on two structurally different mattress samples (with polyurethane core and pocket spring core) using a modified method based on the EN 1957 standard, aiming to understand the long-term effects of mattress characteristics on sleep quality. Preliminary results confirm that the mattress samples can maintain firmness and support during long-term use. The polyurethane foam mattress experienced initial compression but quickly stabilized, while the pocket spring mattress showed slight softening, maintaining overall firmness. For the polyurethane mattress, after the initial drop, the hardness value stabilized, varying between 7.53 and 9.03 N/mm, and at the end of the test, it stopped at 8.60 N/mm. The firmness rating stabilized at 4.3, showing minimal fluctuation between 4.0 and 4.6 throughout the process, while the total height loss was 3.79 mm. The hardness value of pocket spring mattresses generally decreased with increasing test cycles (it started at 5.86 N/mm and ended at 5.21 N/mm). The firmness remained relatively stable, varying between 7.3 and 7.1, and the total height loss was only 2.86 mm. The findings suggest that the firmness of a mattress can be changed with its use, highlighting the need for further research on a larger number of samples in the direction of the long-term implications of these changes on sleep comfort.