Presuming the bones are healing at a good rate you should gradually strengthen your hand and arm muscles with the physio. Your exercises should include sport specific tasks such as pulling on ropes, using a winch, pushing. I would think that if you are not able to do push ups and pull a rope strongly (bu the beginining of December that you will not be good enough for a Hobart race. My husband sails and broke 6 ribs in the race in Bass strait (not much fun!)