Benefits of Sleep Extension on Performances During Total Sleep Deprivation (BankingSleep)

Study Overview
=================
Brief Summary
-----------------
Objectives: investigate the effects of 6 nights of sleep extension on physical and cognitive performances before, during total sleep deprivation (39 hours continuous awaking) and after a subsequent recovery sleep. Design: Subjects participated in two experimental conditions (randomized cross-over design): extended sleep (10-h in bed, EXT) and habitual sleep (8-h in bed, HAB). In each condition, subjects performed two consecutive phases: (1) six nights of either EXT or HAB (2) three experiments days in-laboratory:baseline (BASE), sleep deprivation (TSD) and after 10 h of recovery sleep(REC). Performance tests were administered every 3 hours over the 3-d in laboratory. Setting: This cross-over and randomized study was conducted under standardized laboratory conditions with continuous polysomnographic recording Participants: 14 healthy men (age range: 26-37 years) participated in the study. Interventions: EXT vs. HAB sleep durations prior to total sleep deprivation (39 hr continuous awaking).

Detailed Description
-----------------
Many human endeavors require high-level cognitive performance situations (e.g., health care, military operations, space flight) along the whole nycthemera (i.e. the 24-h cycle). It has long been established that both acute total sleep deprivation (TSD) and chronic sleep restriction impair ability to maintain wakefulness, increase subjective sleepiness and sleep propensity, and most critically reduce various aspects of cognitive performance. In studies conducted in both laboratory setting and different professional situations inducing insufficient sleep, the most consistently and dramatically impacted cognitive capacities were sustained attention and alertness. This degradation of cognitive performance after a period of sleep deprivation is linked to an increase of sleep pressure, e.g. a reduction in the latency to sleep onset or increase of number of involuntary micro sleeps. To identify countermeasures to deleterious effects of sleep deprivation is critical in many professional areas. Management of wake/sleep cycle appears to have an important impact of alertness during sleep deprivation (e.g. sleep habits or physical activity, see the review. Recently, Rupp and coll. (2012) reported that one week of sleep extension realized before one week of sleep restriction (3 h/night) influence the rate of degradation of cognitive performance and alertness during this period and the subsequent recovery period. In other words, they proposed that sleep can be banked before a period of sleep loss and may help sustain performance and alertness. With a different experimental paradigm (i.e. without subsequent sleep deprivation), studies have shown that sleep extension (realized over different periods of time) may improve physical performance, attentional performance, or mood. The fact of increasing total sleep time over a period of time represents an attractive non-pharmacological countermeasure to limit the deleterious effects on performance induced by sleep privation. However, there is no study with cross-over and randomized design to assess effect on relatively short period (6 nights) of sleep extension on performance before, during total sleep deprivation and recovery. Moreover, there is no direct measurement of sleep pressure as continuous EEG monitoring to quantify micro sleep episode during period of sleep deprivation and effect of sleep extension on physical performance is not known. Hence, the aim of this study was to assess the effects of 6 nights of sleep extension (EXT) on physical and cognitive performances, alertness and homeostatic sleep pressure before, during total sleep deprivation and the subsequent recovery day. The investigators hypothesized that EXT would: i) partly prevents the physical and cognitive performances degradation-induced by total sleep deprivation ii) decreases the sleep pressure before, during and after total sleep deprivation and iii) improves the recovery speed of physical and cognitive performances.

Official Title
-----------------
Benefits of Sleep Extension on Cognitive and Physical Performances During Baseline, Total Sleep Deprivation and Recovery (BankingSleep)

Conditions
-----------------
Sleep Deprivation

Intervention / Treatment
-----------------
* Other: Total Sleep deprivation


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: healthy subject voluntary Exclusion Criteria: an average of > 9 h and < 6 h sleep per night a difference > 45 min between week night and weekend night sleep debt sleep disorders medication alcool or toxic consumption up to 300 mg caffeine per day consumption neurologic, cardiovascular, metabolic, pulmonary psychiatric disease or disorder

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 45 Years

Sexes Eligible for Study
-----------------
Male

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Sleep extension<br>Subject spend 10 hours Time in bed per day during 6 nights. This period is follow by a total sleep deprivation intervention (i.e. 39 hours awaking) in laboratory. | Other: Total Sleep deprivation<br>* Subject are submitted to 39 hours of continuous awaking in laboratory and a recovery night<br>* Other names: TSD;|
| Sham Comparator: Habitual sleep<br>Subject respect their habitual Time in bed during 6 nights. This period is follow by a total sleep deprivation intervention (i.e. 39 hours awaking) in laboratory. | Other: Total Sleep deprivation<br>* Subject are submitted to 39 hours of continuous awaking in laboratory and a recovery night<br>* Other names: TSD;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of errors during PVT (n) | number of errors (<100ms or > 500ms) during a10 min Psychomotor Vigilance test (PVT) | Every 3 hours, up to 24 hours of baseline, total sleep deprivation (TSD), and recovery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| median speed during PVT (s-1) | median speed response during a10 min Psychomotor Vigilance test (PVT) | Every 3 hours, up to 24 hours of baseline, total sleep deprivation (TSD), and recovery | 
| number of micro sleep (n) | number of micro sleep (> 5 sec) per hour during baseline, TSD and recovery | Every 3 hours, up to 24 hours of baseline, total sleep deprivation (TSD), and recovery | 
| Sleep latency (min) | Sleep latency during multiple sleep latency test (MSLT) | Every 3 hours, up to 24 hours of baseline, total sleep deprivation (TSD), and recovery | 
| Muscular force (dyn) | Muscular force developed by the subject | At 10:00 on D1 (Baseline), D2 (TSD) and D3 (Recovery) | 
| Response to Trans Magnetic Stimulation (%) | Effect of trans magnetic stimulation on Muscular force developed by the subject | At 10:00 on D1 (Baseline), D2 (TSD) and D3 (Recovery) | 
| Polysomnographic classification (N1, N2, N3, REM) | Evaluation of the duration of each sleep stages during the night before and after TSD | night during DA (Baseline) and D3 (Recovery) | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
sleep extension, attention, physical performance