Why caffeine affects morning people more than night owls 咖啡因對早起鳥的影響為何比夜貓子大

Why caffeine affects morning people more than night owls 
咖啡因對早起鳥的影響為何比夜貓子大
2012-08-09◎國際新聞中心

Caffeine will get you going during the day but could leave you tossing and turning at night – unless you’re a "night owl" to begin with, a new study suggests.
一項新研究顯示，咖啡因會讓你在白天蓄勢待發，但夜裡輾轉難眠，除非你一開始就是夜貓子。

In the study, "morning people" who consumed caffeine during the day appeared more likely than late risers to awaken in the middle of their nighttime sleep.
在這份研究中，早起鳥白天攝取咖啡因，夜裡睡覺時似乎比較可能比晚起的人容易醒來。

Fifty college students were asked to record their caffeine consumption and their sleeping and waking times for a week.
50名大學生被要求記錄咖啡因攝取量與睡眠以及醒來的時間，持續1週。

As college students, they tended to be so sleep-deprived that, for most, "it didn’t matter how much caffeine they had" – they slept well whenever they finally hit the sack, said study researcher Jamie Zeitzer.
研究人員札其爾說，由於大學生睡眠容易被剝奪，「不管攝取多少咖啡因」，他們入睡時都會睡得很好。

However, for the early risers, the more caffeine in their bodies, the more time they spent awake during the night after initially falling asleep. This was not seen in the night owls.
不過對早起鳥來說，血液裡較多咖啡因，晚間初次入睡後醒來的時間較多，在夜貓族裡看不到這種情況。

新聞辭典

toss and turn：片語，輾轉反側。例句： I was tossing and turning all night.（我整晚翻來覆去睡不著。）

rise：動詞，起床。例句：My grandfather rises at 5 every morning to do his exercises.（我祖父每天上午5點起床運動。）

hit the sack：片語，上床睡覺。例句：I’ve got a busy day tomorrow, so I think I’ll hit the sack.（我明天會很忙，所以我想我要睡了。）