Although many students have considered -- but for now rejected -- seeking medical attention, many other young people and their worried parents are consulting their doctors about muscle strains thought to be due to carrying heavy backpacks.

"Sometimes I have shoulder pains. There’s a sore, pulling feeling, and I worry about my spine being bent over all crooked under the weight," Parker said, "But I don’t really have a choice. There’s not enough time between all of my classes to go to my locker."

“Most students are carrying way too much weight in their backpacks and they are carrying them fashionably but improperly, slung over one shoulder," Blass said. According to guidelines from the American Chiropractic Association and the American Occupational Therapy Association, students shouldn’t carry more than 10% of their body weight in a backpack. The backpacks should have two adjustable, padded shoulder straps to equalize the weight and prevent shoulder, neck, and back problems. Although backpacks slung casually over one shoulder may be fashionable, this posture puts further stress on the back and spinal cord. “It puts their skeletons under substantial pressure and stress,” Russwell Windsor, M.D., said, “Overloaded backpacks are contributing to increased visits to doctors’ offices.”

How Much is Too Much?