Modern sports facilities are designed to promote health and performance, yet the cleaning and disinfection practices commonly employed may expose athletes to a substantial chemical burden. The intensive use of quaternary ammonium compounds and chlorine-based agents, combined with elevated levels of volatile organic compounds, particulate matter, disinfection byproducts, and CO₂, can compromise indoor air quality and adversely affect respiratory function, skin barrier integrity, cognitive performance, and overall athletic capacity. This chapter summarizes the main chemical agents used in gyms, outlines their behavior in enclosed environments, and discusses their potential health and performance implications for athletes. It then explores, within the framework of green chemistry principles, the role of enzymatic and probiotic cleaning approaches in reducing toxic load while maintaining hygiene standards. An integrated "Green Hygiene Strategy" tailored to sports facilities is proposed, along with practical recommendations for facility managers, cleaning staff, and athletes. The chapter concludes by emphasizing the need to move towards genuinely "toxin-free" training environments.