The realization that you are getting older can come in waves.

关于你在衰老的提醒会纷至沓来。

You watch movies and point to the actors, saying: “She’s dead. Oh, he’s dead, too.”

看电影时，你指着里面的演员，说：“她已经死了。噢，他也死了。”

Your parents move to a retirement community they call God’s waiting room.

你的父母搬进了一个养老社区，他们称之为上帝的候车室。

You hear more snap, crackle and pop in your joints than in your breakfast cereal.

浑身上下的关节咔哒啪啦作响，比咀嚼早餐麦片还热闹。

In society, youthfulness is glorified and getting older is cast as something to avoid, but as your age increases, your quality of life does not necessarily have to decrease, experts said.

在社会中，青春是一种荣耀，变老是需要避免的事，但是专家说，年龄会增长，你的生活质量却不一定要随之下降。

Here’s what you should know:

以下是一些需要知道的东西：

What is ‘old’?

什么是“老”?

Most people wouldn’t say that a 38-year-old qualifies, but once you pass the median age of 37.8, you may statistically be considered “old,” said Tom Ludwig, emeritus professor of psychology at Hope College in Holland, Mich.

多数人不会认为一个38岁的人“老”，但密西根州霍兰的霍普学院(Hope College)的心理学荣休教授汤姆.路德维格(Tom Ludwig)说，一旦越过37.8这个年龄中值，你在统计学意义上就属于“老人”了。

Studies show that people start feeling old in their 60s, and a Pew Research Center survey found that nearly 3,000 respondents said 68 was the average age at which old age begins.

研究显示人们是在过了60岁以后开始觉得老的，皮尤研究中心(Pew Research Center)的一项调查发现，将近3000名受访者认为68岁是进入老年阶段的平均年龄。

Daniel B. Kaplan, an assistant professor of social work at Adelphi University in Garden City, N.Y., said in an email that living to an advanced age was a relatively recent achievement.

纽约州加登城的阿德尔菲大学(Adelphi University)的社会福利工作助理教授丹尼尔.B.凯普兰(Daniel B. Kaplan)通过一封电邮表示，活到高龄相对来说是人类近期才取得的成就。

“The average human life span gained more years during the 20th century than in all prior millennia combined,” he wrote, adding that the average life expectancy in the United States is 79.1.

“人类平均寿命在20世纪的增幅，比之前的几千年加起来还要大，”他写道，此外他说美国人的平均预期寿命为79.1岁。

“For many people, old age creeps up slowly and sometimes without fanfare or acknowledgment,” he wrote. “While most people enjoy relative continuity over the decades, being able to adapt to the changing context of our lives is the key to success throughout life.”

“对许多人来说，衰老是慢慢到来的，有时候并不会大张旗鼓，往往令你猝不及防，”他说。“虽然大多数人的生活都会在几十年内保持相对的连贯性，但是纵观人的一生，适应不断变化的生活环境乃是成功的关键。”