Normative values for relative schoolbag weight in primary school children aged 6-14 from Czech Republic: A pilot study

Autoři: Mario Kasović aff001;  Lovro Štefan aff001;  Martin Zvonar aff002
Působiště autorů: Department of General and Applied Kinesiology, Faculty of Kinesiology, University of Zagreb, Zagreb, Croatia aff001;  Faculty of Sport Studies, Masaryk University, Brno, Czech Republic aff002
Vyšlo v časopise: PLoS ONE 14(11)
Kategorie: Research Article
doi: 10.1371/journal.pone.0225741


Little evidence from observational studies has been provided regarding ‘optimal’ relative schoolbag load during primary education. Also, no study to date has provided reference-based standards for relative schoolbag weight. Therefore, the main purpose of the study was to establish normative values of relative schoolbag weight in a sample of children. In this cross-sectional study, we recruited 584 primary school students aged 6–14 (meanage±SD = 9.6±2.4 yrs, meanheight±SD = 1.4±0.2 m, meanweight±SD = 37.5±13.3 kg, meanbody-mass index±SD = 17.6±3.1 kg/m2, 44.4% girls) chosen from five schools in the city of Brno. Schoolbag weight and child’s body weight were objectively measured by using digital scale. Relative schoolbag weight was calculated by dividing schoolbag weight with child’s body weight and the result was expressed in percentage. Lambda, Mu and Sigma (LMS) method was used to create sex- and age-percentile curves. Boys carried slightly heavier schoolbag, compared with girls (mean difference 0.2 kg, p = 0.020). No significant differences between sexes in relative schoolbag weight were observed (p = 0.240). Median values (P50) for boys and girls were similar and the largest observed between ages 6–9 in boys (15–17%) and 6–8 in girls (16–18%). The percentage of children carrying relative schoolbag weight beyond 10% of their body weight was very high, especially between ages 6–10 in boys (85.1–100%) and 6–11 in girls (86.8–95.4%). This study provides first sex- and age- relative schoolbag weight normative values in primary school children. Future studies should use similar methods for generating comparable data.

Klíčová slova:

Adolescents – Age groups – Body weight – Cross-sectional studies – Ergonomics – Feet – Children – Schools


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Článek vyšel v časopise


2019 Číslo 11