TY - JOUR T1 - Running economy in early and late maturing youth soccer players does not differ JF - British Journal of Sports Medicine JO - Br J Sports Med SP - 289 LP - 294 DO - 10.1136/bjsm.2007.035915 VL - 42 IS - 4 AU - V Segers AU - D De Clercq AU - M Janssens AU - J Bourgois AU - R Philippaerts Y1 - 2008/04/01 UR - http://bjsm.bmj.com/content/42/4/289.abstract N2 - Purpose: The aim of this study was to investigate the influence of maturity on running economy in a population of young soccer players.Methods: 13 boys (mean age 14.3 years) active in soccer were divided into two groups: 6 early and 7 late maturers. Anthropometrical characteristics, respiratory exchange ratio, heart rate and maximal oxygen uptake were measured. Running economy was assessed at three submaximal running speeds (8, 9.5 and 11 km/h). Allometric coefficients were calculated and used to diminish the effect of body mass. In addition, running style was analysed biomechanically (stride length and meaningful kinematic values).Results: There was no significant difference in the running economy of early and late maturing soccer players, nor any significant differences in mass adjusted physiological values. Therefore physiological differences cannot explain why late maturers succeed in keeping up with early maturers. Late maturing boys take longer relative strides, and have more anteversion of the thigh at heel contact, a smaller knee-angle during swing-phase and a lower mass moment of inertia.Conclusion: Running style seems to be an important determinant in running economy of children. ER -