I had a skin cancer removed from my forearm last Monday. The doctor told me to lay off the gym for about a week, so that I would not put excess strain on the sutures. I went back to full sessions yesterday with no bad side effects. I would give it a week. Since the operation does not involve one of the muscles that you will be working, that should be more than enough time. When you start up, listen to your body. If the site begins to throb, either cut back, or stop.