What's wrong with jumping up and down?

We don't always like it when someone states the obvious to us. For instance, the phrase "jumping up and down" is nonsensical, because we don’t really jump down at all. We jump up and land, then jump up again. But nobody wants to hear about that when they just want to write a good sentence.

That’s why when I copyedit, I’d never correct the sentence “She jumped up and down with excitement” to “She jumped up repeatedly with excitement.” I would probably just leave the original sentence be, even though it's factually wrong.

However, it's so embedded within our vernacular that we easily understand it. I might consider changing the sentence to “She jumped around in excitement,” which is a little more precise, but I would probably run it by the writer first to see what’s truly intended or preferred.

There are rare instances within the English language where tradition and tone are actually a little more important than factual content, and this is one of my favorite examples. Maybe that’s because I really did jump up and down — I mean, jump around — in order to thoroughly research it.