Effect of single and double strap backpack load carriage on vital capacity in school going children

Abstract

Background: There has been growing concern among healthcare professionals, parents, and educators that backpack is damaging the back. Load carriage systems supported by the trunk have been shown to decrease certain indices of pulmonary function by restriction of expansion of the lungs or chest wall. Aims and Objectives: Our study investigated the hypothesis that wearing a backpack with a load ranging from 5% to 30% of body weight (BW) produces pulmonary function reductions in school going children. Materials and Methods: To investigate this hypothesis, 100 normal healthy school girls from two different schools were selected, out of these 57 girls are from schools carrying backpack load and 43 girls from school with no backpack. Depending on the type of school and % of schoolbag weight of their total BW, they were divided into two groups (Group I-carrying backpack load ranging from 5% to 30% of BW and Group II-no backpack). Forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1% and 15 s maximum voluntary ventilation (MVV15) was measured. Results: FVC, FEV1, and MVV15 were decreased significantly in girls from the schools carrying backpack when compared with girls from the schools without backpack and the reduction were approximately proportional to the magnitude of the load carried. No change in FEV1% (FEV1/FVC) as FVC and FEV1 were reduced. Depending on the style with which the backpacks are carried to the school (either on one shoulder, i.e., single strap backpack carriage or both the shoulder’s, i.e., double strap backpack (DSB) carriage) we examined pulmonary functions and found that FVC, FEV1, and MVV15 values were reduced in group carrying backpack on one shoulder when compared with no backpack and DSB. Conclusion: These results indicate a limitation on the ventilatory pump caused by load carriage which is directly related to the load carried and characteristic of restrictive disease of the respiratory system in school going children. Hence, there may be new designs of shoulder pads that could be developed which would provide similar levels of protection without pulmonary restriction. Another alternative may be to provide lockers in the school itself so that schoolbag weight may be reduced. New concept of no bag school is emerging which is also going to be useful.