Today I had my first lesson in Shotokan karate and we did basic kihon like stance, punching, low kick. Then we got into bag work and by the end both my second knuckles were bleeding and my skin was torn off. I am generally a wussy guy with low pain tolerance so I have a few questions. I am wondering if aches and pains are just a part of Shotokan karate and you just have to put up with it if you do it? Do I have to accept that I will get injured sometime if I continue with Shotokan karate? Are injuries inevitable? For example with this video http://www.youtube.com/watch?v=gkGP0AM14F0 , you see guys getting hit in the head and getting concussed. Are these things just a part of life in Shotokan karate? If I am such a wuss, should I just quit now? I really don't like hurting other people so I hate hitting other people and injuring them. But from the looks of kumite, it looks as if hitting others is part of Shotokan karate. I basically just want to learn some self-defence - I don't want to hit people who are not my enemies. Is my thinking wrong? Why do you need to hit innocent people and risk injuries in kumite?