I have got to catch some Zs! 我要休息一会儿!
to catch some Zs: 休息一会儿

Since we are maxed out, we have got to catch some Zs.

Z:联想-->卡通片中卡通人物在睡觉的时候,不就是用英文字母Z表示吗?
外国人想象力倒还挺丰富的哟!

I am maxed out now, so I have got to catch some Zs!
Are you maxed out? Just go and catch some Zs!
Remember: Health is wealth!