If your child is one of the 92 percent of American kids who lug a backpack to and from school, it’s likely she’s cramming it with everything from bulky textbooks and binders to athletic gear and lunchboxes. It’s also likely she’s lugging more weight than is safe. 

Put your kid’s fully loaded backpack on a scale. Ideally it should clock in at no more than 10 to 20 percent of her body weight, says Jill Murphy, a physical therapist and certified strength and conditioning specialist at MotionWorks, a physical therapy center in Neenah, Wisconsin. Don’t be surprised if it’s more than that. According to the American Physiological Society, kids’ backpacks are typically loaded with a total of 22 percent of their weight.

What’s at stake? Back pain, for starters. A 2012 study of teens in Spain found that those kids whose backpacks were in the top 25 percent in terms of weight were 50 percent more likely to have back pain for more than 15 days in a row during the school year.

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“A heavy backpack can cause neck pain and also be a hidden source of headaches,” adds Murphy. That’s because strain in the shoulders can travel upward. There’s even evidence that a too-heavy backpack can damage nerves that run through the shoulders to help hands and fingers make precise movements, impairing a kid’s ability to write or draw well.

Lugging a weighty backpack could also exacerbate an anatomic deformity such as scoliosis, in which the spine curves sideways, Murphy adds. Sogirl with backpack make a backpack pact with your child to follow these tips for lightening her load and keeping her body safe:                                                                         

  • Roll with it. Switching to a backpack with wheels can literally take a load off. You’re more likely to convince a younger kid to switch to a rolling backpack, though, since older ones tend to regard them as uncool. It’s worth suggesting anyway. “Although kids often feel these bags have a stigma,” says Murphy, “they really do save students from carrying all their stuff on their backs.”
  • Don’t lug stuff home that you don’t need for homework. Middle- and high school students are notorious for never editing their backpacks. But that’s what lockers are for. It may take some convincing, but try to get your kid in the habit of stopping by her locker at the end of the day and leaving behind any textbooks or other items she doesn’t need to do homework that night.
  • Take advantage of that precious smartphone. Suggest that your child use her phone or tablet to snap photos of the pages she’s assigned to read rather than haul a huge textbook home.         

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  • Double up. Buy two of items that your child routinely needs both at school and at home — a pair of sneakers to leave in her gym locker, say, or an extra calculator. (Bonus: Your child is less likely to be without something she needs because she forgot to bring it in.)
  • Make some adjustments. A backpack that hangs loosely “puts more torque on the shoulders and increases the possibility of straining them,” Murphy explains. Help your child tighten both straps so that her backpack fits snuggly against her body and its weight is distributed evenly. Encourage her to use both straps.
  • Pack properly. Have your child place the heaviest books in the back of her bag, the part where the straps are attached. This will put the brunt of the weight close to the middle of her back, which can most easily bear the load.

(Photo: MidoSemsem/Shutterstock)