Sports involvement can be both formal and informal at the same time: a comment on Peretti-Watel et al.
Lorente
Fabrice O
FO
D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D013177:Sports / Q000706:statistics & numerical data*; D019966:Substance-Related Disorders / Q000453:epidemiology*