Аннотация: The Russian fitness industry develops under conditions of intense competition, where traditional marketing methods yield to strategies based on trust and social proof. The research analyzes the role of user-generated content and brand ambassadors in forming customer loyalty in fitness clubs. Results show that user-generated content is perceived 9.8 times more authentic than professional content and actively influences purchase decisions. Brand ambassadors, representing the pinnacle of customer engagement, ensure long-term partnerships and audience expansion through personal experience. Comprehensive application of both tools increases customer retention rates and reduces costs for attracting new audiences.