High rebound mattress toppers facilitate core body temperature drop and enhance deep sleep in the initial phase of nocturnal sleep

<div><p>Recently, several new materials for mattresses have been introduced. Although some of these, such as low rebound (pressure-absorbing/memory foam) and high rebound mattresses have fairly different characteristics, effects of these mattresses on sleep have never been scientifically evaluated. In the current study, we have evaluated effects of a high rebound mattress topper [HR] on sleep and its associated physiology, and the effects were compared to those of a low rebound mattress toppers (LR) in healthy young (n = 10) and old (n = 20) adult males with a randomized, single-blind, cross over design. We found that sleeping with HR compared to LR induced a larger decline in core body temperature (CBT) in the initial phase of nocturnal sleep both in young (minimum CBT: 36.05 vs 36.35°C) and old (minimum CBT: 36.47 vs. 36.55°C) subjects, and declines in the CBT were associated with increases in deep sleep/delta power (+27.8% in young and +24.7% in old subjects between 11:00–01:00). We also found significantly smaller muscle activities during roll over motions with HR (-53.0 to -66.1%, depending on the muscle) during a separate daytime testing. These results suggest that sleeping with HR in comparison to with LR, may facilitate restorative sleep at the initial phase of sleep.</p></div

Muscle activity needed to generate a rolling over motion on HR and LR mattress (Roll over evaluations).

<p>Significantly smaller muscle activity (i.e., integrated EMG) was needed to roll over on HR than on LR mattress in 3 out of 4 muscles measured (*p<0.05 by Student’s t-test).</p

Comparisons of sleep and sleep-related parameters between HR and LR mattress topper use (study I).

<p>Comparisons of sleep and sleep-related parameters between HR and LR mattress topper use (study I).</p

High rebound mattress toppers facilitate core body temperature drop and enhance deep sleep in the initial phase of nocturnal sleep - Fig 1

<p>(A) Changes in core body temperature during sleep with HR and LR in young adult males (study I). Larger and longer lasting decrease in core body temperature (CBT) was seen in the initial half of the sleep period with HR (p<0.05 by topper type, p<0.01 by time, p<0.01 by topper type x time, repeated measures ANOVA with a grouping factor). (B) EEG delta power changes across the night (study I). Larger delta-power was observed with HR between 23:00–04:00 (p<0.01 by topper type, p = 0.22 by time, p<0.05 by topper type x time, repeated measures ANOVA with grouping factor).</p

High rebound mattress toppers facilitate core body temperature drop and enhance deep sleep in the initial phase of nocturnal sleep - Fig 2

<p>(A) Changes in core body temperature during sleep with HR and LR in old adult males (study II). As observed in younger subjects (Fig 2), larger decline in core body temperature (CBT) was observed with HR between 23:00–03:00 in old subjects (p<0.01 by topper type, p<0.02 by time, p<0.01 by topper type x time, repeated measures ANOVA with grouping factor). (B) EEG delta power changes across the night (study II). Larger delta-power was observed with HR between 23:00–03:00 (p<0.01 by topper type, p = 0.23 by time, p<0.05 by topper type x time, repeated measures ANOVA with grouping factor).</p

Comparisons of sleep and sleep-related parameters between HR and LR mattress topper use (study II).

<p>Comparisons of sleep and sleep-related parameters between HR and LR mattress topper use (study II).</p