Age Difference in Trunk Kinematics During Walking with Different Backpack Weights in 6- to 12-Year-Old Children

The study reported herein investigated age difference in trunk kinematics during walking with different backpack weights. Two groups of boys, aged 6 and 12 years old, participated in the study. A multiple trial test was conducted with backpacks loaded with 0%, 10%, 15%, and 20% of each subject's body weight. The subjects walked on a treadmill at a self-selected comfortable speed for 20min. The movements of the subjects in sagital plan were filmed and analyzed. The results indicate that trunk inclination angle progressively increased with the increase backpack weight in both age groups. Carrying a load heavier than 15% of body weight resulted in a significantly increased trunk inclination angle when compared to no load. The 12-year-old children showed a significantly lager amplitude in the trunk inclination angle than the 6-year-old children when carrying the same backpack weight.