 Hi, I'm Lisa Smith and I'm a physical therapist at MidMichigan Help. While backpacks are a very convenient and helpful way for students to carry books and other items that they'll need during the school day, if worn improperly, they can cause back and shoulder pain as well as injuries. When getting your backpack ready for school or helping your children pack them, please keep these simple tips in mind. Choose a bag with wide padded straps to properly support weight on your shoulders. Your backpack weight limit shouldn't be more than 10 to 15 percent of your body weight. For example, a student who weighs 100 pounds should not carry a backpack that weighs more than 10 to 15 pounds. When packing your backpack, put your heaviest books in first and closest to the back. Carry your backpack over both shoulders and adjust the shoulder straps so it fits high on your back. Fasten the waist strap if your backpack has one to help evenly distribute its weight. These guidelines are just a few of the ways to make sure you're using backpacks correctly this school year.