When it comes to health and productivity, it's not just about what you do — eating right, exercising, and working hard — it's also about when you do it.

　　当人们谈到健康与工作效率的关系，那就不仅仅关于你的活动内容——饮食均衡，体育锻炼，努力工作了，而且还关于你进行这些活动的时间。

　　Chronobiology is the study of internal clocks, how they differ among people, and how you can adjust your daily schedule to suit your unique biological rhythm. Each person's rhythm, or chronotype, is different.

　　时间生物学研究的是人类内部的时钟，也就是不同人之间生物钟的区别，以及你如果通过调整日常行程活动以适应你个人独特的生物节奏。每个人的节奏，或生物钟，都是不一样的。

　　According to psychologist and sleep specialist Dr. Michael Breus, there are four chronotypes, which he labels dolphins, lions, bears, and wolves. Roughly half the population is made up of bears; the rest is split among dolphins, lions, and wolves.

　　根据心理学家和睡眠专家迈克尔?布易鲁斯医生的研究，他总结出了四个类型，并以海豚，狮子，熊和狼作为每个类型的标记。大约有一半人都属于熊型，另外的一半就属于海豚型，狮子型和狼型。

　　Keep in mind that it's virtually impossible to have a perfect day every day, so make the changes you realistically can.

　　要谨记的是，我们几乎无法每天都过得十分完美，所以你还得按照实际情况作出调整。

（编辑：何莹莹）