The Singaporean researchers found that in sleep-free conditions during an intensive study, five hours of sleep during the night and one and a half hours of sleep during the day had a better effect on the cognitive ability of adolescents than one night's sleep for 6.5 hours. As reported in an article published in the magazine sleepSuch a regimen also has a drawback – elevated blood sugar levels.
The optimum length of sleep in adolescence is from eight to ten hours. Due to the fact that older students and students, in addition to attending school and university, need to maintain active social life and participate in other extracurricular activities, they often do not receive the required amount of night sleep, which can also affect their academic performance . This is largely due to the need for an early rise: a recent study showed that the change of lesson hours later in two schools in Seattle allowed students not only to sleep for more than half an hour but also to improve the assessments.
In the new work, the scientists at the Duke-NUS Medical School under Michael Qi decide to understand how the cognitive abilities and the health of adolescents will be affected by the changes in the usual pattern of sleep under the pressure of time. To do this, they asked 58 adolescents (aged 15 to 19) to move to a dormitory for several days, followed by polysomnography each evening.
For the first two nights, participants were allowed to spend nine hours in bed, then divided into two groups. During the next five days the participants' sleep was limited to 6.5 hours: the first group was sleeping this night, and the participants in the second group slept during the night for five hours, after which an hour and a half were provided in the afternoon. Then, for two more nights, the participants also slept nine hours a night, after which the sleep was restrained for another three days.
The duration of sleep at 6.5 hours is not chosen by accident: it is half an hour below the average duration of night that the participants are sleeping at the usual time. By changing the way of rest, scientists wanted to recreate the situation of lack of sleep, which often happens during exams or intensive training.
Analysis of the data collected by the polysomnography shows that, on average, group participants who sleep five hours at night and one and a half hours during the day are sleeping 15-20 minutes less than those in the first group. However, participants in the second group are distinguished by better working memory, processing speed and less drowsiness. In addition, their mood during the day was better: at the same time, it should be made clear that the mood and cognitive abilities of the participants are generally worse during sleep restraint than in those days when they were allowed to sleep up to nine hours a night.
The only drawback of torn sleep is the result of the glucose tolerance test: the blood glucose level of participants in the second group is significantly (p = 0.03) higher than the blood glucose level of participants in the first group.
Despite the fact that sleep breakdown during night and day rest periods proved to be more effective for the cognitive abilities of adolescents, scientists have clarified that this regimen has its own deficiency, which is expressed in a higher glucose level and as a result of increased risk of developing diabetes. The authors insist that adolescents should adhere to healthy sleep hygiene and an optimal sleep duration of eight hours.
Last fall, scientists also showed that lack of sleep is associated with risky behavior among adolescents. You can read about it here.