Under the Covers: The Effect of a Temperature-Controlled Mattress Cover on Sleep and Perceptual Measures in Healthy Adults.
Level 2 - randomized trial
Individual randomized crossover trial in humans
PubMed 41133665 · doi:10.3390/clockssleep7040055
What was done
In a randomized, counterbalanced crossover trial, 34 healthy adults (20 females, 14 males; age 30 ± 5 years) used a temperature-controlled mattress cover for 14 nights following at least 3 nights of familiarization. Active temperature control was turned on for 7 nights (POD) and off for 7 nights (CON). Objective sleep was assessed using wrist actigraphy, while heart rate (HR), heart rate variability (HRV), and respiratory rate (RR) were recorded using embedded mattress sensors. Subjective sleep quality, thermal comfort, and thermal sensation were captured via daily and weekly questionnaires.
What was found
Linear mixed models demonstrated statistically significant improvements favoring the active temperature condition across all daily perceived outcomes (all p < 0.05), including a large improvement in perceived sleep quality (p = 0.001, d = 0.92). No statistically significant differences were observed between conditions for objective sleep metrics or biometrics (HR, HRV, RR; all p ≥ 0.05).
Why it matters
Thermal regulation of the sleep surface can notably enhance subjective sleep quality and comfort in healthy adults, though these perceived benefits do not immediately correspond to detectable physiological or actigraphy-based changes.
Limits
The study had a small sample size (n = 34) of young, healthy adults, limiting generalizability to populations with sleep disorders. Blinding was likely imperfect because participants can physically perceive temperature changes, introducing potential placebo or expectancy effects. Objective sleep was evaluated with actigraphy rather than gold-standard polysomnography, and the 7-night duration per arm was short.
Cited by
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