Working intensity of children walking with different school bag loads in Multan - Pakistan

ABSTRACT

In Pakistan anecdotal evidence of shoulder, back pain in school children is alarming but no scientific studies have been carried out yet. This study was carried out to find out any association between pain and school bag carriage in students, since almost all school management including public and private in Pakistan putting extra loads on the children in the form of heavy school bags. Children are in the phase of growth and development. So there is continuous endanger of growth and developmental retardation due to growth due to pulling heavy school bags load not only but also some sort of body aches and pains occur. To determine the relative working intensity of children walking with different school bag loads. Fifty male children, aged 9-15 years were selected from a primary school of Multan city to carry school bags of 10, 15 and 20% of their body weights, and no load was used as control. Heart rate, blood pressure, respiratory rate, education proficiency, tiredness of every subject was measured using a continuous incremental protocol. In the load carriage test subjects walked 500 meter [at a school distance]. Based on the results of heart rate, blood pressure, respiratory rate, tiredness walking intensity at different load conditions were calculated. Heart rate of subjects were monitored and recorded by electrocardiograph until five minutes after walking. Blood pressure was measured before, immediately, 3 and 5 minutes after every trial. There was a significant difference found on the human working intensity between 10 and 20% body weight load conditions, but not among the 0%, 5% body weight load conditions. Heart rate responses among all load conditions showed similar trends, 60% maximum heart rate was obtained at different load conditions among the subjects. It is concluded that 10% body weight is recommended as the weight of school bags for children