From grade-school students to adults, it seems like everyone is carrying a backpack these days. When worn correctly, a backpack can be a comfortable way to transport all the things you need for work, school, or play.
A backpack’s two straps distribute the load evenly across both shoulders, putting less strain on the body than, say, a tote bag, briefcase, or messenger bag. And backpacks with hip belts and sternum straps can further distribute the weight so it’s not all sitting on your shoulders.
But wearing a backpack incorrectly, or carrying one that’s too heavy, can have harmful effects on the spine. Incorrect backpack use is associated with back pain, neck pain, bad posture, and intervertebral disk compression, possibly leading to a herniated disk.
Unfortunately, it appears that many backpack users, particularly young ones, are putting themselves at risk of pain and musculoskeletal injuries.
In a study of 650 schoolchildren published in March 2018 in the , researchers found that more than 85 percent of students were carrying their backpack incorrectly, and about 40 percent of them had a backpack that was disproportionate to their size.
So how should you be wearing a backpack? Here’s what the experts have to say.
Buy the Right Size Backpack, and Don’t Overload It
The right size backpack depends on your body size and, more specifically, your torso length, measured from the base of your neck to your waist (top of the iliac crest). Many outdoor gear shops can measure your torso and advise you on what size backpack will fit best. Once it’s on, the pack should feel comfortable, with the top of the pack riding slightly below shoulder level and the bottom of the pack at about waist level.
The same principle applies for children’s backpacks. Parents should have their child try on a backpack before buying it to make sure the pack is no larger than the child’s back. The top of the pack should sit just below the child’s shoulders, and the bottom of the pack should sit at the waistline.
Keep in the mind that the size of the backpack is different from its capacity, or how much you can put in it. A size small day pack may have a capacity of anywhere from about 18 to 35 liters, depending on the model you choose.
The more capacity you have, the more stuff you may be tempted to put in your pack, but “a fully loaded backpack should not weigh more than 15 percent of a person's weight,” says Anissa Jones, a chiropractor and clinical director of Total Health Chiropractic and Wellness Center in Macon, Georgia.
If you must carry more, pay attention to how the weight is distributed. “Within the bag, place heavier items so they sit closer to the spine. This helps make the bag feel lighter, so your spine endures less stress,” says Thanu Jey, a chiropractor and clinic director at Yorkville Sports Medicine Clinic in Toronto.
Pick Up Your Bag Properly, Without Twisting Your Spine
It’s easy to grab your backpack quickly off a chair or the floor without thinking about how that action may affect you. But lifting a heavy pack using improper technique can cause back pain.
Ideally, you should face your pack and stand with your feet shoulder width apart. Bend your knees and squat “so your weight is on your heels, with a straight back. Keep the backpack close to your body as you lift it off the ground, and use both hands. Avoid lifting from the side or twisting motions,” says Kevin Hallmeyer, a chiropractor and the owner of True Spine Chiropractic in Bend, Oregon.
Once you’re standing upright again, swing your backpack onto your back.
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Avoid Wearing a Backpack on One Shoulder
Once you’ve properly lifted your backpack, don’t hurt yourself by wearing it improperly.
“Backpacks should always be worn with both straps and positioned so the top [of the bag] is just below your shoulders and the bottom is above your hips,” says Hallmeyer.
Think of wearing your pack like this as a way to keep the weight centered instead of being pulled to one side or the other, something that can lead to chronic pain.
“[Wearing a backpack] over one shoulder can affect the spine, ribs, shoulders, and neck. It should be situated so your arms are free to move in a normal walking pattern. Any restrictions in arm movement can create a phenomenon known as spinal fixations, which are a ‘locking up’ of the spinal bones,” says Eugene Charles, a chiropractor and director of the Applied Kinesiology Center of New York in New York City. “This can lead to scoliosis, trouble breathing, and overall tension.”
Jey concurs: “Using one strap only will shift your spinal alignment and can bring on postural changes to your muscles and spine in the long run.”
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Don’t Let Your Backpack Hang Too Low on Your Back
Once you’ve got both backpack straps on your shoulders, the final step is making sure your body isn’t getting dragged down by a low-hanging bag.
“The mistake most people make is letting the backpack hang too low, without tightening the arm straps enough,” says Theresa Marko, a physical therapist and the owner of Marko Physical Therapy in New York City. “This causes undue pressure on your neck and shoulders as well as some banging on your lumbar spine and sacrum. This also affects [the way you walk] since your center of gravity is pulled off, and you have to lean forward to compensate.”
“If the pack is too low, it acts like a weight that pulls you back,” Hallmeyer explains. “To compensate, we shift our upper back and head forward to counter the weight.”
According to Hallmeyer, this can contribute to a hunched posture — similar to the posture many people assume when using their smartphones — and muscle pain. Avoid the hunch and chronic pain by simply tightening your backpack straps.
Marko also recommends using the chest and belly straps found on many backpacks. While they may not be stylish, fastening them helps to stabilize the weight you’re carrying.
Backpacks are a great way to carry everything you need throughout the day. Make sure your backpack is working for you rather than against you by practicing these backpack safety tips as you go.