Clip opens with health care worker measuring a boy's cardio endurance. Child is breathing rapidly to get heart rate up and is hooked up to an EKG monitor. Narrator discusses kids in middle years joining organized games. Shot of boy approximately 12 years old playing softball. Narrator discusses the casualties of too much stress on joints in the middle years. Still shot of boy after he pitches a ball. Narrator discusses the damage resulting from little league elbow.