The art of taekwondo requires one to use his leg more than other martial art but it does should not make your muscles sore unless one is not condition. The most important thing to remember is when kicking in the air during class, one must not imphacise power over techique. I know many people with bad knees and hips. This Message was edited by: [CT]pizzaboy on Aug 6, 2001 3:02pm