You have some misconceptions about exercise. (Though it is true that improperly done exercises can injure you.) Since this is a rationality forum and not really the place for such a discussion, I will just point you and anyone else interested towards the /fit/ FAQ: http://www.liamrosen.com/fitness.html
You have some misconceptions about exercise. (Though it is true that improperly done exercises can injure you.) Since this is a rationality forum and not really the place for such a discussion, I will just point you and anyone else interested towards the /fit/ FAQ: http://www.liamrosen.com/fitness.html