Truly delete rows from a sheet to make it smaller, and the file faster

I know how to delete rows. However, if you add, say, 30,000 rows of data to a sheet and then delete all of them, the sheet itself still remembers that you had added a bunch of rows and consequently stores 30,000 blank rows. This makes the file take up a lot more memory and operate much more slowly. So my question is this:

Is there any way to truly delete rows so that Excel is no longer storing tons of extra, empty rows? The solution I've been using is to simply create a new workbook and replicate all the sheets by copying into it the header rows, first row of formulas, macros, named ranges, etc. While generally manageable, it's a bit of a pain in the ***.

I've searched extensively on Google but haven't come up with anything. Thanks in advance for any help that can be offered.