Of corse 🙂 it burns some calories and builds muscle. Once muscle is built, then it gives you the opportunity to burn MORE calories throughout the day by doing simple things (even sleeping or buying groceries!) I highly recommend it. A tip is to do these muscle-toning exercises in the morning, so you continue to work your muscles and burn calories throughout the day.
It sure does; however, it is very important to stretch before doing squats. Also maybe jogging in place to get your blood flowing before you do squats. I learned the hard way and my legs were in so much pain the next day. It’s not a good feeling, and it’s dangerous to not stretch before these exercises.