The importance of a varsity sports, beyond the fitness level, is the team aspect. Sacrificing yourself to better the team kind of thing. Team first mentality. Additionally, beyond being a member of a varsity sport, is demonstrating your leadership via team captaincies. Because as a team captain, you have demonstrated your ability to lead others. And the confidence of your peers/coaches to do so.
You will need demonstrated leadership, exceptional (not ‘fairly good’) academics (good grades in the hardest classes available), and be physically fit. No one thing will be enough for an appointment. They look at your ‘whole person’.
You can go to USAFA’s website and view class profiles to see what successful candidates are bringing to the table.
Lastly, don’t give up if this is your dream. You have 1.5 yrs to present your best package! And if you don’t get in on your first try, reapply Many successful candidates are re-applicants. Many come from their prep school. And many choose to proceed though other means, ie AFROTC. Make sure and think about also applying for a solid plan B.
Good Luck!!