Traditional methods to normalize aerobic fitness (VO 2max) have been considered inadequate for not properly adjusting the effects of body size in children, adolescents and adults. Allometric scaling (Y=aX b) has emerged as an efficient method to compare individuals of different body dimensions. Studies aimed to compare VO 2max in individuals with different body sizes should use methodology that properly accounts for the body size effect, thereby avoiding misinterpretation and reaching the potentially wrong conclusion. The use of allometric scaling for studies aimed to compare aerobic fitness in children and adolescents who dramatically vary in body size is strongly recommended. Resumo – Métodos tradicionais de normalização da aptidão cardiorrespiratória (VO 2max) têm sido considerado inadequados por não ajustarem adequadamente os efeitos do tamanho corporal em crianças, adolescentes e adultos. A alometria (Y=aX b) tem demonstrado ser um Palavras-chave: Alometria; Composição corporal; Consumo de oxigênio. 710 Allometric scaling to normalize VO 2max in children Cunha et al.