Varsity sports participation can play a significant role in a service academy application for two main reasons:
1) The obvious, physical fitness and athletic skills.
2) The leadership opportunity, and other traits desirable in future junior officers: team player, collaboration, time management, determination, working through exhaustion/discomfort/pain, putting others ahead of self, strategic plannng and execution, communications, commitment, etc.
That said, if you crush the CFA, demonstrate you regularly participate in physical fitness activities and show strong evidence of your leadership talent and other desirable traits in other activities, you can create a desirable well-rounded profile. I am not talking about a rubber-stamp club presidency, but something where you actually led activities and made a tangible difference, something you can talk about in essays and interviews. Is there a failing club you can take over, revive and make successful? Is there something you can start and drive to success?
I randomly pulled up USAFA Class of 2026 stats - you can see the varsity sport element.