Local health experts understand the impact an overloaded backpack can have on a child or teen – stiff neck, sore shoulders and aching backs. But parents can help prevent these possible pains in a few simple ways.

Encourage your child to use his or her locker whenever possible if one is provided at school. You may also periodically encourage your child or teen to go through his or her backpack and clear out any unused textbooks, binders, papers and other accumulated belongings. This way he or she is not toting unnecessary items back and forth to school. Ask your child to tell you if he or she is experiencing any pain or discomfort from the backpack so you can make sure it is adjusted properly and not too heavy. Talk to your child’s doctor if any pain persists.

How do I know if my child’s backpack is too heavy?

When you pick up your child’s backpack, you may well be surprised at just how much it actually weighs. As a general rule, to prevent injury a full backpack should weigh no more than 10 to 20 percent of his or her body weight.

How a student wears the backpack is often just as important as its overall weight. Make sure the backpack is properly fitted so the weight is distributed evenly across the back and shoulder area. It is definitely not a good idea to wear the backpack hanging from just one shoulder or side of the body as this will cause and aggravate muscle pains.

How do I know how much my child can carry safely?

There is a simple calculation.

Child’s weight x .15 = max backpack weight

This means that, for example:

• A 50-pound child should carry a maximum of 7.5 lbs.
• A 100-pound child should carry a maximum of 15 lbs.
• A 150-pound child should carry a maximum of 22.5 lbs.

Keep this calculation at hand as your child grows and gains weight.

Are there any other ways to make sure my child can avoid pain from carrying a heavy backpack?

When choosing a backpack, follow these tips:

• Buy a backpack with wide, padded straps to minimize pressure on the shoulders and collarbone.
• Consider a backpack with wheels or a waist belt to help take weight off the back. Remember, though, that a backpack with wheels will still need to be carried up stairs.
• Leather is fashionable, but it’s heavier than nylon and can add unnecessary weight to the pack.
• Look for a backpack with a padded back as this can protect against objects with sharp edges inside the pack and increase carrying comfort.

Are there any important things to know about how to carry a backpack?

Your child should follow these guidelines:

• Carry the pack on both shoulders to spread the weight evenly.
• Tighten the straps so the bag is close to the body. The straps should hold the backpack so that it sits about two inches above the waist.
• Bend both knees instead of leaning over when hoisting a heavy bag.
• Pack the heaviest items closest to the center of the back to minimize additional strain. Make sure the weight is evenly distributed across the pack by using all the available compartments.

Cara Barone, M.D., is a board-certified pediatrician at the Palo Alto Medical Foundation’s Palo Alto Center. Advice is not intended to take the place of an exam or diagnosis by a physician.