Whereas most people require more than 6 h of sleep to feel well rested, there appears to be a group of people who can function well on between 3 and 6 h of sleep. The aims of the present study were to compare 12 naturally short (3-6 h) sleepers (9 males 3 females, mean age 39.6 years, SD age 10.1 years) recruited by a media publicity campaign with age, gender and chronotype matched medium lengt...

BACKGROUND A significant U-shaped association between sleep duration and several morbidity (obesity, diabetes or cardiovascular disease) and mortality risks has been regularly reported. However, although the physiological pathways and risks associated with "too short sleep" (<5 hours/day) have been well demonstrated, little is known about "too much sleeping". PURPOSE To explore socio-demograp...

The purpose of this study was to determine the relationship between quality of sleep and autonomic nervous functioning in healthy adult Japanese women using three measures, namely, the Pittsburgh Sleep Quality Index (PSQI) for subjective assessment of sleep quality, actigraphy for objective assessment of sleep, and heart rate variability using high frequency and low frequency domains. Participa...

We derived descriptive characteristics related to habitual sleep duration and insomnia for individuals newly diagnosed with sleep apnea/hypopnea syndrome and evaluated how sleep apnea/hypopnea syndrome, insomnia, depression, and sleep duration relate to sleepiness and fatigue. In total, 100 participants were divided into three sleep groups: short (<7 hours), long (≥ 8 hours), and midrange (7-7....

Too much sitting, and both short and long sleep duration are associated with obesity, but little is known on the nature of the relations between these behaviours. We therefore examined the associations between sleep duration and time spent sitting in adults across five urban regions in Europe. We used cross-sectional survey data from 6,037 adults (mean age 51.9 years (SD 16.4), 44.0% men) to as...

BACKGROUND As a result of the American Academy of Pediatrics' recommendation that healthy infants be placed on their side or back for sleep, the percentage of infants sleeping prone has decreased dramatically. With the increase in supine sleeping, pediatricians have questioned if there are differences in the rate of acquisition of early motor milestones between prone and supine sleeping infants...

BACKGROUND Poor sleep quality is common and is associated with poor quality of life and health status in patients with heart failure. However, few investigators have focused on the impact of impaired sleep quality on survival in heart failure. OBJECTIVE To examine whether self-reported sleep quality is associated with prognosis in patients with heart failure. METHODS The study sample consis...

In this study, a wheel-rail transient rolling contact model capable of accounting for the nonlinear displacement-force properties hanging sleepers is proposed. The sleeper status affected by rail irregularities an input analysis behavior and related degradation in terms plastic deformation fatigue. results indicate that severity significantly geometric characteristics relative position with res...