Hey , I m a 14 year old teen (footballer) and i ve been masturbating for over two years whenever i finish masturbating , i feel guilt but more important tired and less energetic . Moreover, it really affect my knee badly and i can prove that , i ve played two matches , my knees were like shaking and i m not in the best form whenever i masturbate one day before any game or match. I wanna know whether its really bad for the knees , the back and the wrist and how to stop masturbating ? also any other negative effects ... thanks in advance .