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Updated: Feb 3, 2026

Experimental Methods to Study Human Postural Control
Published on: September 11, 2019
A prospective 1-year study on load reduction of school backpacks shows reversible changes of body posture in
Julia J Grannemann1, Sonja Holzhauer2, Siegmar Blumentritt3
1Department of Anesthesilogy, Klinikum Bielefeld, Bielefeld, Germany.
Background:
The impact of backpack carrying on body postural changes in schoolchildren has been discussed intensively. However, findings are inconsistent mainly due to the lack of long-term results.
Objective:
The purpose of this investigation was to study the influence of backpack weight on body posture and prevalence of back pain.
Methods:
In our prospective, comparative study, we investigated the influence of backpack weight on 77 schoolchildren (average age 10.8 ± 0.7 years) over a 1-year period. Participants were evaluated at the beginning of the study by clinical examination and formal static posture analysis. Forty-nine students comprised the control group while 28 students in the intervention cohort had the weight of their backpacks reduced by 2 kg. All students were reevaluated after 6 and 12 months by formal postural examination.
Results:
Children with reduced backpack weights had a significantly improved bending posture when wearing their backpacks when compared to the participants of the control group, whereas the analysis of the children while they did not wear their backpacks revealed no difference between the groups. Within the follow-up period all postural changes were reversible once the backpack weight was removed.
Conclusions:
Schoolchildren with heavy backpack loads show postural changes while carrying their backpack but this impact was reversible when backpacks were removed. Continuous reduction of backpack loads minimizes prevalence of back pain.
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