Forgive me if this appears as trolling, but I find it baffling that anyone can say "I want to practice specifically with X type of patients or Y conditions" or "I really want to work in Z setting"
Your experiences in courses, with classmates, and especially in clinics may radically alter your interest several times in your first year alone.
Start with a big scope and then narrow it as you become more informed.
A pre-med advisor told me he marks down applicants who, when prompted with the question 'what type of medicine do you want to practice', answer with a specific field or specialty. The reason being that it is so short sighted to possibly believe you know enough about said field to make an informed decision, you're just grasping at straws.
FWIW- Sports medicine is competitive and growing in Pod, but not lucrative or desirable IMO. Yeah, it's 'cool'- but athletes have the crappy combination of needing a lot of attention without a lot of treatment (meaning less $$$).