August 12, 2010 – Sleeping longer during one night would not be enough to overcome the lack of sleep for several consecutive nights, concludes an American study1.
The clinical trial was conducted in the laboratory on 159 individuals, on average 29 years old.
After two 10-hour nights of sleep, 142 people got 4 hours of sleep for five consecutive nights. Thereafter, each was randomly assigned a “dose” of recovery sleep for one night, that is, from 0 to 10 hours.
The other 17 participants served as a control group and slept 10 hours per night throughout the study.
According to the results, participants deprived of sleep during the 5 nights performed worse on tests of attention, concentration and reaction than the control group.
The attention, concentration and response capacity of people who had slept 6, 8 or 10 hours during their recovery night improved, but remained below the average for the control group. The harmful effects of sleep deprivation were even more significant for subjects who did not sleep or slept only 2 hours during the recovery night.
Several full nights would therefore be necessary to fill an accumulated lack of sleep and thus allow the brain to regain its sharpness, the researchers note.
|
Sleeping too much or not enough could harm the heart Sleeping more or less than 7 hours per night increases the risk of developing cardiovascular disease, another American study reveals2. According to the results, people who regularly sleep less than 5 hours a night would double their risk of having heart problems. And those who sleep more than 9 hours would increase this risk to one and a half times. Researchers observed that excess sleep would have an effect on endocrine glands and metabolic functions, while insufficient sleep could lead to decreased glucose tolerance, insulin sensitivity or increased blood pressure. The researchers analyzed data from the National Health Survey of 30,397 adults in 2005. |
Carole Boulé – PasseportSanté.net
1. Banks S, Van Dongen HPA, et al. Neurobehavioral dynamics following chronic sleep restriction: dose-response effects of one night for recovery, Sleep, 2010; 33 (8): 1013-1026.
2. Sabanayagam C, Shankar A. A sleep duration and cardiovascular disease: results from the National Health Interview Survey. Sleep, 2010; 33: 1037-1042.
