What Is A Good Major For Someone Who's interested in Biology?

I'm a 19 year old gym enthusiast in college. Even though i may be young i believe i am better educated about the human body then most people. i am familiar with the muscular, skeletal, cardio vascular and nervous systems of the body, and how cellular processes play a role in weight training and protein synthesis and nutrition is key and so on..blah blah blah..What major is right for a guy like me?