I use that when I am on holidays without my sax. After doing 80 - 100 such "push-ups" I press the lips together FLAT for 10 seconds. Relax and repeat 10 times in total. The last is also from Larry Teal's book.A speech and language pathologist friend of mine taught me an exercise for strengthening muscles associated with your embouchure, and I later saw a version of it in Larry Teal or Dave Liebman's book (maybe both?):
Protrude your lips while saying/ thinking "oooooo," (think like an ant eater or blowing out candles), then protract/ draw back the corners of your mouth while saying "eeeeee" (think flat to get all the muscles...if you smile too much, you don't get all the muscles). You can add manual resistance as indicated (I would recommend washing your hands first :bluewink.
Like any other strengthening exercise, start small and build up as you increase strength. I would start with 2-3 sets of ten every time you get in the car or sit down to watch television.
These are also a good warm up for your chops if you are rushed to get on stage, or don't have a place to really get warmed up on the horn.