doi:10.1007/s12187-025-10276-0engLegaz-Arrese, AlejandroMayolas-Pi, CarmenOviedo-Caro, Miguel ÁngelPano-Rodriguez, ÁlvaroLópez-Laval, IsaacNavarro-Gómez, MiguelSitko, SebastianAssociations between the Level of Competition and the Type of Sport with health-related Quality of Life in AdolescentsART-2025-145099Adolescence is a critical period marked by significant physical, psychological, and social changes, with physical activity (PA) playing a pivotal role in health-related quality of life (HRQoL) outcomes. This cross-sectional study aimed to investigate the relationship between PA, sports participation, and HRQoL among adolescents, considering gender, age, maturation, competition level, and type of sport. A total of 9383 adolescents aged 11–19 completed assessments of PA, HRQoL, and demographic variables. Participants were classified based on PA levels and sports competition levels. HRQoL was assessed using standardized measures, including the KIDSCREEN-52 questionnaire. Girls reported lower scores in physical and mental HRQoL domains compared to boys, starting from Tanner maturation stage 3. All HRQoL domains, except social acceptance, declined with age and maturation, with a more pronounced decline in girls. Inactive adolescents exhibited the lowest HRQoL levels across all domains. Competitive athletes demonstrated better HRQoL than non-competitive peers, with improvements in self-perception and social acceptance at higher competition levels. Sport type influenced HRQoL outcomes, with gymnastic sports associated with lower autonomy and peer relationships, while racquet sports showed better outcomes. This study highlights the complex interplay between PA, sports participation, and HRQoL among adolescents. Tailored interventions promoting physical activity and supporting young athletes’ psychosocial needs are essential for enhancing HRQoL during this critical developmental stage.2025http://zaguan.unizar.es/record/16257010.1007/s12187-025-10276-0http://zaguan.unizar.es/record/162570oai:zaguan.unizar.es:162570info:eu-repo/grantAgreement/ES/DGA/S25-23RChild Indicators Research (2025), [19 pp.]byhttps://creativecommons.org/licenses/by/4.0/deed.esinfo:eu-repo/semantics/openAccess