What willit take to become a physical therapist in sports medicine?

Masters or PhD: That's a great question. First a pt undergrad degree and lots of experience in sports medicine. Most go on to get a masters or phd in pt as well with some research work. Then intern with an amazing group that will give you experience treating athletes.

Sports therapists: As a matter of semantics you are talking about a sports physical therapist not sports medicine which implies a doctor. Many physical therapists who have special interests in sports therapy had an undergrad degree in athletic training making them a pt/atc. Many physical therapy degrees are now going on to the doctorate level; i.E, a doctor of physical therapy; but they cans subspecialize.