Your brain on sleep debt
Sleep doctors have long preached the importance of getting a full night's sleep-which, for most adults, is somewhere between seven and nine hours a night. Studies show that when people consistently get less than six, it can negatively affect their health, including their metabolism and their cardiovascular system. Even temporary periods of short sleep can lead to impairments in mood and concentration levels.
睡眠医生长期鼓吹夜间睡眠的重要性--对于大多数成年人而言，也就是每晚睡7至9小时 。研究表明当人们持续每晚睡眠低于6小时时，他们的健康会受到负面影响，包括影响新陈代谢和心血管系统 。即使只是短暂的缺觉也会导致情绪不好、注意力不集中 。
One recent study, for example, found that when people got less than six hours of sleep a night, they had trouble completing basic tasks: They had a fivefold increase in attention lapses and their reaction time nearly doubled, compared with people who slept seven or more hours, even when they didn't feel tired or realize that their performance was suffering.
例如，一项最近的研究发现：与睡眠时间7小时及以上的人相比，当人们一晚睡不到6小时时，他们会很难完成基本任务 。注意力不集中的次数增了5倍，反应时间几乎翻了一番，即使他们并没有感到疲劳、或没有意识到自己的效率降低 。
New research may advocate for weekend catch-ups
A study published this week in the Journal of Sleep Research provides a beacon of hope that maybe some of these negative effects can be made up for by getting extra sleep over the weekend. The study followed more than 43,000 adults in Sweden for 13 years and compared death rates in that time period with participants' self-reported sleep habits.
本周发表在Journal of Sleep Research期刊上的一篇研究点燃了希望之灯：也许有些消极作用可以通过周末多睡睡得以弥补 。该研究13年来在瑞典随访了43000多位成年人，并将这段时间的死亡率与受试者自称的睡眠习惯进行了对比 。
The researchers found that adults younger than 65 who consistently slept five or fewer hours were 65% more likely to die early than those who slept six to seven hours a night on average. (Sleeping eight or more hours a night was also associated with an increased risk, of 25%.)
研究员发现：对于年纪低于65岁的成年人而言，平均每晚睡眠不高于5小时的人比每晚睡6至7小时的人的早死率高65% 。（每晚睡8至9小时也可能增加25%的死亡风险 。）
But those who reported short sleep during the week and long sleep on the weekends seemed protected: Despite skimping on shuteye Sunday through Thursday nights, they had no increased mortality risk compared to those who consistently got six to seven hours.
In today's day and age, many of us aren't sleeping as much as we should: We stay up late, but are still forced to wake up early, thanks to all of those societal obligations-like work and school and spin class-first thing in the morning. So when the weekend rolls around, it can be tempting to sleep in, in an attempt to catch up on all those lost hours.
现而今，很多人的睡眠时间都不足：我们熬夜，但早上还是被迫早起，这都是因为我们的社会义务--比如工作、上学和动感单车课--逼自己早上起床的第一件事 。所以周末的时候，多睡睡具有很大的诱惑力，以补上那些丢失的睡眠时光 。