The start of school is just around the corner and back-to-school shopping is already underway. Before your children hit the books again, make sure their backpacks are not causing them unnecessary strain.

"When a backpack is heavy, the child hyperextends (arches) the back or leans the head and trunk forward to compensate for the weight of the bag. This stresses the muscles in the neck and back, increasing the risk of fatigue and injury," says Shelley Goodgold, PhD. About 5,000 schoolchildren are taken to the emergency room each year due to overloaded backpacks. Here's how you and your child can help prevent injuries and strain:

• Use a hip strap for heavier weights.
• Use a backpack with wide, padded straps and a padded back.
• Use both of the backpack's straps, firmly tightened, to hold the pack two inches above the waist. (Using only one strap over a shoulder puts excess strain on muscles.)
• Keep your child physically active to maintain strong back and abdominal muscles.
• Teach correct lifting techniques. Demonstrate how to bend with both knees when picking up a heavy object.
• Place the heaviest items closest to the back.
• Help your child pack the backpack neatly to prevent jostling and uneven weight distribution.

The American Academy of Pediatrics recommends children carry no more than 10 percent to 20 percent of their own body weight and all backpacks should weigh less than 15 pounds.

Sources: www.kidshealth.org and Top Health newsletter.