The phrase "as much as I used to....."

Question

Hello guys so I have a problem with an expression. So here are two sentences:

I do not run as much as I used to.

I do not run as much as I used to do.

I don't know which one of the two phrase is the correct one. I would be glad if you could help me out.

Answer 1

I do not run as much as I used to.

I do not run as much as I used to do.

Both examples are natural.

They are not phrases; they have both the subject and predicate and are hence clauses, independent clauses in fact as they express a complete idea.