Association of Leisure Time Physical Activity and Back Pain in Brazilian adults - Lemes, Italo R. [UNESP]; Fernandes, Romulo A. [UNESP]; Turi-Lynch, Bruna C.; Codogno, Jamile S. [UNESP]; Monteiro, Henrique L. [UNESP] (Lippincott Williams & Wilkins, 2019)