Good question, and it sounds like you probably do have good experiences to draw from here. Both the elements of leading the team, AND working as a team (so, leadership and teamwork), can likely be conveyed.
I often suggest people try to write a sports example more like a personal diary entry, and less like a sports news story.
So yes you need to include the "What", of what happened in a given situation or season or whatever, but most important is the WHY... why was this scenario important to you and your life or your development? What did you learn about leadership and/or teamwork? How did you influence or motivate the rest on the team? How did your experience on the team influence how you approach the rest of your life, even your professional life? How will the skills you gained there, translate into your future career and working with teams in the business world (and/or even at b-school)?
Hope that helps!
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