How are Heavy Backpacks Effecting Youth Development?
"Heavy loading of the spine may induce musculoskeletal problems in children. Chinese surveys reported frequent overloading of schoolbags carried by primary school children
"Forty-three primary school children, mean age 9.6 years underwent spirometry lung-function measurements, while adopting the following five conditions in random order: free standing; kyphotic standing; standing wearing a backpack weighing 10%, 20% and 30% of their body weight.
The Outcome: This study demonstrates a restrictive effect on lung volumes when a school-bag load is heavier than 10% of a child's body weight. Our results also confirm the detrimental effect of a kyphotic posture on pulmonary mechanics" (2001).
Now, as that quote was taken from an article written about 18 years ago, the sorts of items that school children carry now a days have changed. Below is a study done in 2018, of what kids carry today, and why we should still be concerned over their health.
"Items carried by students in their day-to-day school bags have been found to include, but are not limited to, laptops, books, pencil cases, scientific calculators, sports uniforms, school day uniforms and sport-specific training clothing, up to three types of shoes (sport-specific footwear, school leather shoes, and general runners), lunch boxes and full water bottles . To address the requirement to carry backpacks weighted down by all these items, the review by Mackenzie et al.  recommended the provision of school lockers. However, with school lockers being removed from many schools in recent years due to vandalism and security fears , anecdotal evidence suggests that school children are often required to carry their backpacks, loaded with all of these items for long periods of time. In addition, loads may be increasing due to increases in the size of school backpacks and increases in loads carried due to changes in the school curriculum (e.g., more homework being assigned, and increases in after-school/extracurricular activities) and the carriage of emerging items (like laptops) [14,15,16]. The need for children to have to carry a full day’s class schedule of schoolbooks, in addition to other items and supplies (e.g., sporting and musical equipment for after-school/extracurricular activities), throughout the day is thus a growing concern . The sight of young children marching off to school heavily burdened by backpacks, coupled with a rising rate of non-specific back pain among schoolchildren, has led to increasing parental and community unease " (2018).