Seattle's Child

Your guide to a kid-friendly city

Look at those huge backpacks on those small kids. A good rule of thumb is the backpack should not exceed 15% of your child's body weight. (Photo: iStock)

Heavy backpacks can be a big problem for kids

Ask the Pediatrician: Tips for safely wearing (and not overpacking) that backpack.

By now you may be in the back-in-school tempo of morning routines, homework, and the commute to school. Feels good, right? I want to focus on a couple of things that can throw that rhythm off. First, we’re going to discuss those heavy backpacks. Carrying too many books and other supplies can cause grumbling, but it can also injure your child’s back and shoulders. More on that below.

Second, let’s work to avoid time out sick. Get an influenza vaccine in the fall for protection throughout flu season. And COVID-19 vaccinations and boosters do a very good job in preventing severe illness and hospitalization. Children aged 6 months and older are eligible for a primary vaccination series against COVID-19, and children 12 and older are eligible for a booster dose.

Thanks for everyone’s thoughtful questions, keep them coming. (Got a question for Dr. Block? Send it to

Heavy backpacks can be a pain

We’ve all seen it, a 100-pound kid with what looks like a 100-pound backpack. As much as we want to build strength in our kids, this is not good for them.

From 2017 to 2019, an estimated annual average of 7,500 kids under 19 years old were treated in emergency rooms for injuries and pain related to backpacks. Let’s stop that before it happens and run through what’s OK for kids.

When a backpack is fully loaded, it shouldn’t weigh more than 15% of the child’s body weight. For a child that is 100 pounds, you want to make sure the backpack doesn’t weigh more than 15 pounds. Use a scale with the loaded pack to check.

Signs your child is carrying too heavy a load include taking the backpack on and off a lot, complaining about pain in their shoulders or arms, or posture changes like being slumped over. If you see any of those signs, it’s time to change course.

A smaller, lighter pack may help. Look for one with lightweight materials like nylon or canvas, and wide, padded shoulder straps with a waist belt that transfers some of the weight to the hips. If your child has to carry a lot, a pack with wheels can help, just keep in mind if they’ll still need to get that bag up any stairs (or through Seattle’s puddles).

What’s wrong with this picture? He’s using just one of the backpack straps, that’s what. (Stock image)

Heavy backpacks: what you can do

Encourage your child to use their locker (if they have one). That is what it is there for. Like adults, kids need to lift safely too. Teach them to use their knees and squat when picking up a bag or putting it on.

About putting it on: Use both straps. Backpacks have two shoulder straps for a reason and that is to distribute the weight evenly. Slinging the bag over just one shoulder might seem convenient, but it can lead to back and shoulder pain. Using the waist belt, tightening the straps for a snug fit and standing up straight while wearing a pack are all good habits.
Encourage your children to tell you about any pain or soreness. If your child is having back pain or neck soreness, rest and these modifications may help. If it lasts for more than a few days, talk to your doctor.


More health in Seattle’s Child:

Help your kids give back to their community and their world

COVID vaccines for kids ages 5-11: what parents need to know

About the Author

Susanna Block

Dr. Susanna Block, MD, MPH, is a pediatrician with Kaiser Permanente in Seattle and lives with her family in Queen Anne.