Experts say back-to-school time can mean back problems for kids carrying loads of books in their backpacks.

According to experts, kids carrying backpacks improperly or using backpacks that are the wrong size can take a toll on their bodies over time. They say it can cause both spine and muscle pain.

Experts say parents and children need to pick the right backpack in order to prevent problems. They urge parents to make sure the backpack sits centered on a child?s back and that the straps are adjusted to distribute weight on the shoulders and hips, not the spine.

Parents also need to be aware of how much weight their children are carrying in the packs. Chiropractic physician Dr. Greg Birsky advises children to carry about 10 percent of their body weight, no more than 15.

Birsky says parents need to tell their children to lift and wear their backpacks properly, using both straps, buckles and good posture.

For a full interview with Dr. Greg Birsky, go to channel 612 on your iO digital cable box and select iO Extra.