It definitely requires an immense amount of time and commitment. I walked on to my Div 1AA football team freshman year and it was tough with classes and labs along with practices, lifting, meetings, and games. It's possible, but usually athletes choose easy majors so they can concentrate more on athletics.
I'm a PCA working in the ED. We do EKGs, vitals, finger sticks, blood draws, send labs, take out IVs, get supplies, change linens, transport pts, hook pts up to monitors, and anything the nurse tells us to do. We can also assist in (only hooking pts up to monitors asap) or observe traumas since I work at a teaching hospital.
I'm a SN-PCA at Mass General and they have their own PCA training and have a phlebotomist teach us and supervise us as we practice our blood draws. Once we do the required hours of phlebotomy, we are signed off and are allowed to do blood draws on our own. Oh, and I work in the ED.