Mean sleep duration in hours (SD).
Sleep/activity parameters (total sleep, mean sleep episode duration, maximum sleep episode duration, number of sleep episodes, and activity while awake) were analyzed for each 12-hr period of light or dark conditions and averaged across 3 days.
Middle and bottom plots: show 3-day means of total sleep, mean sleep episode duration and number of sleep episodes quantified in 12-hr day/night bins.
Kronauer and C.A. Czeisler, "Circadian Regulation Dominates Homeostatic Control of Sleep Length and Prior Wake Length in Humans," Sleep, Vol. 9, No. 2 (June 1986), 353 364.
The mean sleep disturbance score was 26.7 ± 9.9.
During the night of the sleep studies, EE was measured with a metabolic cart (indirect calorimetry with canopy), including basal metabolic rate (BMR), mean sleep EE, lowest sleep EE, ratios of mean sleep EE/BMR, and lowest sleep EE/BMR.
In general, the inter-relationship between sleep and headache seems to interest also the sleep length: an excess or lack of sleep or a bad quality or inadequate duration of sleep could cause headache [2, 4].
That manner of tracking paints a picture of sleep length, but offers little in the way of quality.
As expected in a sample with a high number of participants with obstructive sleep apnea, the amount of minutes with deep sleep (S3 and S4) and REM sleep as well as the mean sleep efficiency were somewhat low.
