Naps can charge your brain's batteries
小憩可以给大脑充电

A NASA-funded study on astronauts found that naps up to two and a half hours long improved working memory performance. Working memory involves focusing attention on one task while holding other tasks in memory, so a poor working memory could result in errors, according to a NASA news release.
美国国家航空航天局资助的一项针对宇航员的研究发现，长达两个半小时的小憩可以提高工作记忆能力。美国国家航空航天局称，工作记忆包括将注意力集中在一项任务上，同时记住其他任务，因此工作记忆差可能会导致错误。

Taking a nap may make you more alert for the period right after you wake up and maybe hours into the day. A short snooze may also make you feel more relaxed.
小憩一下，你可能会在醒来后的一会儿甚至几个小时内变得思维更加敏捷。短暂的小睡也会让你感觉更放松。

You'll have lower risk for heart problems
小憩会降低患心脏病风险

Taking a nap once or twice a week could lower the risk of heart attacks or strokes, according to a 2019 study published in the journal Heart.
2019年发表在《心脏》杂志上的一项研究表明，每周小睡一两次可以降低患心脏病和中风的风险。

After tracking more than 3,400 people between the ages of 35 and 75 for slightly more than five years, the researchers found that those who indulged in occasional napping -- once or twice a week, for five minutes to an hour -- were 48% less likely than those who didn't nap to experience a heart attack, stroke or heart failure.
在对年龄在35岁到75岁之间的3400名研究对象进行了五年多的跟踪调查后，研究人员发现，那些偶尔小憩的人——每周一次或两次，每次5分钟到1小时——比那些没有小憩的人患心脏病、中风或心力衰竭的可能性低48%。

It might even help you get into shape
小憩可以帮助保持身材

A 2020 study focusing on women found the more sleep-deprived the women were, the more likely they were to consume added sugar, fatty foods and caffeine.
一项2020年针对女性的研究发现，睡眠不足问题越严重的女性就越有可能摄入额外的糖、脂肪食物和咖啡因。

A lack of quality sleep could lead to overeating because inadequate sleep is believed to stimulate hunger and suppress hormone signals that communicate fullness. The findings were important because women are at high risk for obesity and sleep disorders, the researchers said, which can both be driven by a high intake of food.
缺乏高质量睡眠可能会导致暴饮暴食，因为睡眠不足会引发饥饿，抑制传递饱腹感的激素。研究人员称，这些发现很重要，因为女性肥胖和睡眠障碍的风险很高，两者都可能是由大量摄入食物造成的。

Napping has been found to improve the overall quality of even nighttime sleep.
人们发现，小睡一觉可以改善夜间睡眠的整体质量。

And boost your creativity
提升创造力

The right side of your brain might experience a mental spark during a nap, research has suggested. The right side is the hemisphere most associated with creative tasks, such as visualization and thinking, while the left is more analytic.
研究表明，小憩时右脑可能会产生灵感。右脑与想象、思考等创造性活动相关，而左脑则更善于分析。

Researchers monitoring the brain activity of 15 people found that the right side of their brain communicated busily with itself as well as with its left counterpart. The left side of the brain, however, remained relatively quiet. In a January 2020 study of 2,214 Chinese adults ages 60 and older, participants who took afternoon naps for five minutes to two hours showed better mental agility than those who didn't nap.
研究人员对15人的大脑活动进行了监测，发现他们的右脑不仅活跃，还与左脑进行了频繁的交流。然而，左脑保持相对平静。2020年1月一项对2214名60岁及以上中国成年人进行的研究显示，午睡5分钟到2小时的受访者比不午睡的受访者思维更敏捷。

错误午睡姿势损害健康

趴桌午休时如严重弯曲头部和胸部，会对颈动脉、心、肺、胃肠等器官造成一定程度的压迫，增加心、肺负担；再加上食用午餐不久，体内血液更多地流向胃肠帮助消化吸收，导致供向头部的血液不足。结果，头部氧气供应随之不足，醒后可能出现头晕、眼花、耳鸣、呼吸不顺等大脑缺血缺氧症状。因此，午饭后不宜立即午睡。

另外，趴桌午睡时心率逐渐减缓，一定程度上加重了脑部缺血症状，造成人体植物性神经系统功能暂时性紊乱，具体表现为耳鸣、腿软、脚麻等症状。

长时间趴桌睡还会诱发颈椎、脊椎疾病、呼吸道疾病、手肘尺神经疾病等。

这样午休才健康

首选姿势当然是平躺着睡。如果实在没有条件平躺，次选的姿势是半坐位斜躺。配备一张可将靠背斜放的躺椅，再加上枕头、眼罩等，也能有个好的午睡。

如果连躺椅都无法配备的话，可以选择坐着睡。把U形枕套在脖子上，让颈椎处于一种比较自然的状态，再找一个有靠背的椅子，坐着闭目休息。

来源：CNN 科普中国