Effects of a modified backpack model on ground reaction forces in children of different ages during walking and running
Date
2022Author
Version
Acceso abierto / Sarbide irekia
Type
Artículo / Artikulua
Version
Versión publicada / Argitaratu den bertsioa
Impact
|
10.31083/j.jomh1805109
Abstract
Background: Backpacks are widely used by children to carry different objects and the literature supports that most backpacks contain
excessive weight. To minimize the loading effects (i.e., ground reaction force), modified backpacks have been tested. However, the
effects of elastics on shoulders straps are yet to be studied. Thus, the aim of this study was to test and compare the effect on the ...
[++]
Background: Backpacks are widely used by children to carry different objects and the literature supports that most backpacks contain
excessive weight. To minimize the loading effects (i.e., ground reaction force), modified backpacks have been tested. However, the
effects of elastics on shoulders straps are yet to be studied. Thus, the aim of this study was to test and compare the effect on the vertical
ground reaction force of a standard backpack with a modified one with elastic straps while walking and running. Methods: 9 children
(5 boys and 4 girls) were included in the group G-5 (age: 11.0 ± 0.3 years-old; body mass: 35.3 ± 7.3 kg; height: 1.41 ± 0.1 m) and
twelve (7 boys and 5 girls) in G-9 (age: 15.0 ± 0.7 years-old; body mass: 56.7 ± 11.2 kg; height: 1.63 ± 0.1 m). Participants attended
a single session and were initially asked to walk and then run over a force plate. The software Ergotest MuscleLab v8.0 (MuscleLab,
Ergotest Innovation, Porsgrunn, Norway) was linked to the force platform and was used to collect and export data. The level of statistical
significance was set at p ≤ 0.05. Additionally, the effect size of the differences verified on T-Tests was calculated based on Cohen’s d.
Results: Statistically significant differences between a common backpack and a modified one with straps (p < 0.05) were observed for
the variables time and force when walking. Regarding the running condition, the time variable did not differ significantly between the
backpacks. However, the force variable changed considerably between backpack types (p < 0.05). The new straps minimized the forces
magnitude, resulting in lower stress. Conclusions: The modified backpacks with shoulder elastic straps reduced the ground reaction
force and impact when walking and running. The study may encourage other researchers to assess the effects of different movements
(such as jumping or rotating) on ground reaction force. [--]
Subject
Backpacks,
Modified straps,
Ground reaction forces,
Locomotion
Publisher
IMR Press
Published in
Journal of Mens Health 2022 18(5): 109
Departament
Universidad Pública de Navarra. Departamento de Ciencias de la Salud /
Nafarroako Unibertsitate Publikoa. Osasun Zientziak Saila
Publisher version
Sponsorship
This work is supported by national funding through the Portuguese Foundation for Science and Technology, I.P., under the project UIDB/04045/2020.