After years of martial arts training, I have damaged several toes, two fingers, my spine, and one rib. I have had ripped tendons and other muscular damage that has taken from months to years of healing. Never had any damage after getting the black belt. I guess becoming more proficient helps.
I guess the required daily exercise helps strengthen the muscle enough to protect imnternal organs. However, the risk of practicing kumite or sparring is damage.
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