TUCSON, AZ (Tucson News Now) - Lucy Chant carries about 20 pounds of school supplies in her backpack every day.
Adding to Lucy’s load are textbooks, snacks and after-school sports gear.
“By the end of the day, it probably feels like 40 pounds,” Lucy told CBS New York’s Tom Hanson. “When you’re tired and walking from class to class, it’s a lot.”
Lucy, 14, isn’t unusual.
A new study shows that weight can take a major toll on a student’s back.
Dr. Ken Hansraj co-authored a study that measured how wearing a backpack impacts the spine.
“For example, 10 pounds in your backpack then the forces on the spine is seven times, which is 70 pounds of force,” Hansraj said. “So if you’re struggling uphill 20 degrees, the forces become 120 pounds.”
Hansraj said carrying too heavy a load puts children and teens at risk for long-term health problems because they’re stressing areas of the spine and core that are still growing.
He recommends young children carry no more than 10 percent of their body weight. The recommendation is 15 percent for teens and 20 percent for adults.
Hansraj said using both straps, keeping them tight, and practicing good posture can also reduce pressure on the spine.
"Good posture is your ear above your shoulders and your angel wings back," Hansraj said.
Lucy said she makes sure she carries her backpack the right way.
"It's not normal at first, but once you put in the time and you definitely feel a difference," she said.
She said she is trying to convince her friends to do the same.