Document Type : Research Paper
Lecturer, Department of Physical Education and Sport Sciences, Payame-Noor University, Tehran, Iran
Assistant Professor, Department of Sport Medicine and Health, Faculty of Physical Education and Sport Sciences, University of Tehran, Tehran, Iran
The aim of this study was to investigate the effect of the height of placement (lower and middle) of two types of backpacks (conventional backpack and modified backpack) with 10% of body weight on the kinetic (including 1st and 2nd peak, minimum force, and loading rate) and kinematic (including cadence, step length, step width, swing and double support phases) parameters of gait in schoolchildren. 28 school boys participated in the study after their inclusion and exclusion criteria were considered. They were evaluated by Gaitway treadmill in four conditions including backpack-low, backpack-middle, modified backpack-low, and modified backpack-middle. ANOVA test with repeated measures showed that the mean of the first and second peaks of the backpack-middle was higher than other conditions and had a significant difference with the backpack-low (P<0.05). Among the backpacks, the minimum vertical force in the backpack-low was more than both modified backpack conditions (P<0.05). Given the increase in the first and second peaks of the backpack-middle compared with the backpack-low, it seems better to place the backpack in the lumbar region in terms of forces applied to the body, but this difference was not observed for the modified backpack.