When I started running in my 30s, I realized running was a battle against myself.

当我30多岁开始跑步时，我意识到跑步是一场与自己的较量。

youdao

When I started running in my 30s, I realized running was a battle against myself, not about competition or whether or not I was athletic.

我30多岁开始跑步时，我意识到跑步是一场与我自己的较量，这不是一场比赛，也不关乎我是否是名运动员。

youdao

I was afraid that if I started running the man would take after me.

我害怕如果我跑起来，那人会追来。

《牛津词典》

"I was running away and they started shooting and a bullet hit the chest of a young man of maybe 18,19.He died."

VOA: standard.2010.07.01

Well, they said the same thing about me when I started running in New York.

CNN: Obama tops new national polls

But I remain as fundamentally optimistic now as I was when I started running in 2007.

WHITEHOUSE: Remarks by the President at a DNC Event in Washington, DC

Hanging from 100 feet of rope in the middle of El Cap, I started running back and forth across the smooth face.

WSJ: El Capitan's Nose in a Day | By Michael J. Ybarra