ASK YOUR SURGEON. Too many variables so ask your doctor simple superficial lumpectomy away from the axilla 2 to 4 days.- no heavy lifting no bench presses. Larger, deeper, closer to axilla 7days due to discomfort i allow stair master or jogging with limited arm motion after 7 days but every case is individual. No swimming for a week. You should be golden at 3 weeks - all depends - on your situation!