This is why I think lifting is over rated, as someone who was a body builder in college. Doing bjj at a dojo inherently ties your fitness to a social aspect so not only are you accountable to your teammates, you push each other's progress forward each class.
Discussion
I've done a little of most (as an amateur and pro) at different points in my life. What they all share in common is discipline and commitment. If you're on the mat or the pumpatorium at 5am, You're probably not out drinking late the night before and You're probably being mindful of what you put in your body.