like ovaboost says. Probably best to learn how to box or do martial arts. Its a discipline so you wont tend to want to raise your hands at any chance you get. Its not all about the size. When i boxed i was cruiserweight and sparred against a much smaller guy, middleweight i believe. He hit me 3 or 4 times and i hardly saw the punches coming. All about technique and accuracy if you ask me. Now im 6ft 3 and 18st because i gave up boxing and took up powerlifting, but my speed has gone. viscious circle