I am 25 and have been punching bags pretty regularly since I was 5 years old. I am tired of hitting bags. They did build my power and cardio, but its getting kind of monotonous. Probably gonna have crazy arthritis when I get older. I also feel that its taking a toll on my shoulders. They definitely work, but It takes a lot out of me. You can theoretically shadowbox for hours. Would it hurt to just do an extra 10-15 minutes of padwork/drills and skipping the bag work? I will still hit the bag, but its not my sole focus in the gym because I have one at home.