Nutrients would be the answer!
She should probably avoid football, wrestling and cheer-leading, both of these demand some amount of strength - I'd be able to answer better if you had given a list of sports.
Track/Swimming/Tennis/Soccer/Golf: These would all probably be fine.
Strain
Strain is known to be an injury that affects the muscle or tendon by causing twist or tear of a tendon or muscles. Thus, strain can either be complete or partial tear of the muscles or tendon or simple overstretch of the tendon or muscle. Furthermore, strain can be classified as chronic or acute strain.
