Effects of backpacks on ground reaction forces in children of different ages when walking, running, and jumping

Backpacks for transporting school loads are heavily utilized by children, and their mechanical advantages have been allowing children to transport heavy loads. These heavy loads may increase ground reaction forces (GRFs), which can have a negative effect on joints and bone health. The aim of this st...

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Detalles Bibliográficos
Autores: Barbosa, João, Marqués, Mário C., Neiva, Henrique P., Esteves, Dulce, Alonso Martínez, Alicia, Izquierdo Redín, Mikel, Ramírez Campillo, Rodrigo, Álvarez, Cristian, Marinho, Daniel
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2019
País:España
Institución:Universidad San Jorge (USJ)
Repositorio:Academica-e. Repositorio Institucional de la Universidad Pública de Navarra
OAI Identifier:oai:academica-e.unavarra.es:2454/36869
Acceso en línea:https://hdl.handle.net/2454/36869
Access Level:acceso abierto
Palabra clave:Backpack
Children
Load-carriage
Gait
Ground reaction forces
Descripción
Sumario:Backpacks for transporting school loads are heavily utilized by children, and their mechanical advantages have been allowing children to transport heavy loads. These heavy loads may increase ground reaction forces (GRFs), which can have a negative effect on joints and bone health. The aim of this study was to investigate the effect of backpacks on the GRFs generated by children during walking, running, and jumping. Twenty-one children from the fifth (G-5, n = 9) and ninth (G-9, n = 12) grades walked, ran, and jumped over a force plate. When walking, the G-5 had GRF increments in the first (17.3%; p < 0.001) and second (15.4%; p < 0.001) peak magnitude, and in the total integral of the vertical force (20%; p < 0.001), compared to the control condition (i.e., no backpack), and the G-9 had increments of 10.4%, 9%, and 9% (p < 0.001), respectively. The G-9 did not prolong their total stance time (p > 0.05), unlike the G-5 (p = 0.001). When running, total stance time increased 15% (p < 0.001) and 8.5% (p < 0.001) proportionally to the relative load carried, in the G-5 and G-9, respectively. Peak GRF did not increase in any group when running or landing from a jump over an obstacle. It was found that GRF was affected by the backpack load when walking and running. However, when landing from a jump with the backpack, schoolchildren smoothed the landing by prolonging the reception time and thus avoiding GRF peak magnitudes.