Congratulations on choosing sports medicine as your future career! Here are some resources to get you started in researching the options.
"The prerequisites for sports medicine programs are more varied and new programs are being created every year. Here’s a link that might be a useful start: http://sportsmedicine.about.com/cs/jobs/a/aa121299.htm. Students interested in these kinds of programs are encouraged to gain practical experience in a physical therapy or sports medicine/training clinics to be sure it is what they want. Individual faculty instructors or advisors usually prepare letters of recommendation for students interested in programs in sports medicine."