title: [Trends in Six Years Participation in Extracurricular Physical Activity in Adolescents. The AVENA and AFINOS Studies].
authors: David
authors: D
authors: Martínez-Gómez
authors: Miguel
authors: M
authors: Martín-Matillas
authors: Oscar L
authors: OL
authors: Veiga
authors: Ascensión
authors: A
authors: Marcos
mesh_terms: D005260:Female; D006801:Humans; D007899:Leisure Activities; D008297:Male; D009043:Motor Activity; D016272:Occupational Health