Muscular strength is a limited resource, and athletic techniques help to use this resource efficiently.
Conclusion
A requirement for an athlete to become a champion is a superior mastery of athletic techniques.
Evidence
Muscular strength is a limited resource. Athletic techniques help use it efficiently. Top athletes don't differ much from each other in muscular strength.
Evaluate
The conclusion is signaled by "it follows that." Everything that comes before is the support: muscular strength is the limit, technique is what efficiently uses it, and top athletes are roughly equal in strength — so the differentiator at the championship level must be technique. The main point is the championship-requirement claim.
Goal
Find the answer that says, in some form: an athlete must have superior mastery of athletic techniques to become a champion.