The Weight of Knowledge - Schoolbooks and Your Kid's Back

This is the time of year where mothers and fathers across the land begin to worry about what gear their students need for school, and questions about school backpacks come up time and again.

What’s the heaviest backpack my child should wear? What is too heavy – is there a maximum weight or is it based on a percentage of body weight? Is there a maximum time per day a heavy backpack should be carried? How do I choose the right backpack: cool looks-form-and-design or fit-and-function? One strap or two, multiple compartments or one, padded or unpadded, waist strap or not? What’s the best way to wear a backpack, high on the back, low on the back, one strap or two?

If my child has back pain, is it from the back pack design, improper wear, improper loading, excessive time, my child’s deconditioning or obesity? If the backpack is too heavy in childhood and adolescence and causes pain, will my child have pain later life as a result? If my child complains of neck and back pain, is it always the fault of the backpack? How do the teachers and medical societies weigh in? Since 2011 alone, more than 6,000 articles are in print in the medical literature addressing these issues.

So, what’s the background information, and how common is back pain in kids? And is it always the fault of the backpack?

Among children between the ages of 11 and 14 years, almost 40% complain of neck and lower back pain. Of those in pain, 80% attributed their pain to backpack use. Several ergonomic studies show immediate deleterious effects of children standing, walking, climbing stairs, and balancing with excessively heavy backpacks. Heavy backpacks can cause neck shoulder and back muscular problems such as postural compensation and strain, and makes kids more prone to injury and falling especially if the loads are unbalanced. Girls complained of neck and back pain more than boys, especially if they wore the pack with one strap. Adolescents complain more of back pain when the packs are heavier and are worn for longer periods of time, such as more than the 10 minute average from bus to class.

But that’s not the whole story – it’s not always the pack.

Sedentary lifestyle is possibly the most important factor determining back pain among schoolchildren. Lack of physical activity contributes to loss of muscle strength and tone in the lower back. Students who complain of back pain after carrying their packs often complained of pain before carrying packs. Studies report that back pain in children is often related more to psychosomatic factors and daily experience with back pain rather than use of a backpack. Children who were deconditioned or referred to themselves as “sedentary” or felt fatigued while carrying their backpacks during the usual 10 minute walk from the bus to class, had more back pain than the children who described themselves as “fit or active”.

Given that we can’t be 100% sure where the pain is coming from, what do we recommend is the heaviest the pack should weigh?

I recommend limiting backpack weight to 10% of body weight. (A 100 pound student should carry 10 pounds). Up to 20% of body weight is the maximum load that can be carried safely, according to several medical societies (pediatrics, physical therapy and orthopedics), although there is no absolute consensus. We all know that these recommendations are ignored routinely. In the United States more than 9 out of 10 children carry backpacks that weighed more than 10% and up to 22% of their body weight. Those carrying the heaviest backpacks complained of pain 50% more than the others.

The good news is, no study has ever shown that carrying a backpack that’s too heavy leads to more problems later in life or to the development of problems like disk herniations or scoliosis. It just hurts now. The bad news is, children who have headaches, backpain and anxiety now often complain of the same symptoms later in adulthood.

But what about the backpack? There is no perfect backpack. Backpacks vary in design depending on what they’re intended use might be, such as for long trips, marching, camping, or daily use for school. My best recommendation for the backpack based on the research is as follows:

1. Two shoulder straps with a chest compression strap.
2. Plenty of lower back padding, and a waist strap.
3. Skip the water bottle or carry it empty to school.
4. Two compartments in the pack, and load the heaviest objects in the compartment closest to the spine.
5. Wear high and tight on the back rather than low and loose.
6. Try the backpack on as if you were trying on a pair of shoes. Bring some books with you, load the pack, and have your student walk around the store with that. Quickly, function and fit will supersede looks and coolness.

To all parents, here is the obvious conclusion: until all books are on CD ROM or available 100% online, students will be carrying heavy packs to and from school. So remember, max pack weight of 10% of body weight is best, never more than 20%. And kids, stay fit and get off the couch.