I haven't had reconstruction so I'm not sure what the rules are about that. Are you on any hormone therapy that may compromise bone density as that would be something else to be concerned about? Generally, I think you need to work up slowly if you haven't been doing much but as to what you can do... I would suggest that you see an exercise physiologist who knows about cancer treatment to be sure. Boxing sounds great fun - rowing, etc is good but I'm not sure what the difference between pulling and pushing would be. Hopefully, someone else can help with better info.