Original scientific paper
THE IMPACT OF SCHOOL BAG MASS ON CHILD'S HEALTH
Mario Kasović
orcid.org/0000-0002-4660-6900
; Faculty of Kinesiology, University of Zagreb, Zagreb, Republic of Croatia
Martin Zvonar
; Faculty of Sports Studies, Masaryk University, Brno, Czech Republic
Martin Sebera
; Faculty of Sports Studies, Masaryk University, Brno, Czech Republic
Abstract
Many scientists agree that the weight of the school
bags is one of the most important factors that may affect
the health and proper growth of the child, especially in
elementary school. The aim of the research is to determine
the effect of weight of school bags on the appearance of
asymmetry of the lower extremities. Protocol research
measured the vertical load Fz ground reaction upon
contact with the ground at the foot simulated movements
in the laboratory. Motions that child performes
spontaneously in one school day were selected for
simulation. The tests, involving the following
movements, are: walking on a flat surface, walking up the
stairs and walking down the stairs. Tests were carried out
with and without the bag. For data collection, processing
and analysis of signals, BTS was used, Elite system that
contains a platform for measuring ground reaction force,
manufacturers Kistler. To test statistically significant
difference between limbs, Student's t-test for dependent
variables with error inference of 0.05 (p <0.05). was used.
As a right-handed, subject predominantly uses his right
leg which is evident in the increased maximum force
values in tests of walking on a flat surface and walking up
the stairs. Conversely, in demanding test walking down
the stairs maximum force is less than the maximum left,
with and without bag. Research indicates that the
application of external loads can lead to the asymmetry
and differences between limbs, which can not be
quantified by visual inspection. In particular, this
difference between the right and left legs is visible in the
most demanding test of a walk down the stairs with a bag,
which recorded four differences that extend through all
three main stages walk. In everyday life, these statistically
significant differences may indicate a deficit of muscle
strength, and with inadequate physical activity and
reduced levels of physical activity, may be a potential
cause of injury of the spine and musculoskeletal system of
the child with the consequences that will follow him
throughout life.
Keywords
gait; school bag; force; health
Hrčak ID:
136936
URI
Publication date:
31.12.2014.
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