Healthy Me

My little sister is in training to compete in fitness.  It's not body building.  She called it flexible something or other.  It's about being lean but in shape.  It sounded like it was about being able to build muscle without building it up so much that your shape was no longer feminine. I'm not sure that is the right word for it but that's about the only way I can think to describe it. She's eating right and using a trainer. It sounds very healthy anyway.