Remember this acronym: S.L.A.M.
What daily habit might be causing your back, hip, knee, and shoulder pain—or possibly even leading to more serious conditions like plantar fasciitis, bursitis, or tendonitis? According to orthopedic surgeon Barbara Bergin, MD, it’s that thing you do without even thinking each time you sit down: crossing your legs.
A 2014 study in the Journal of Physical Therapy Science looked at changes in posture when participants sat cross-legged for extended periods of time. After sitting cross-legged for three hours (a totally normal occurrence in today’s office culture), researchers noticed the participants had more slouched shoulders, a rotated pelvis, and a forward head posture. That’s because crossing one leg over the other requires you to bear more weight on one side, which could overtime lead to changes in the musculoskeletal system.
The solution? Dr. Bergin gives her female patients one simple acronym: S.L.A.M., or “Sit Like A Man.” Alright, let’s get one thing straight: It’s not that men have better posture than women—far from it!—but they tend to do something with their legs that may prevent these bodily aches as you age. Turns out, it’s all about the knee placement.
Dr. Bergin recommends sitting with the knees pointed slightly outward, in 11:00 and 1:00 positions. (Nope, that’s not manspreading, but it will feel drastically different if you’re used to pinning your knees together or crossing your legs while you sit.)
“When you rotate the hip inward,” says Dr. Bergin, “your knees naturally fall into a knock-kneed position, which increases the stress across our iliotibial band and incidentally our knees.” (FYI, the iliotibial band connects the pelvic, outer thighs, and knees, and stabilizes the joints.)
To use S.L.A.M. for better posture, here’s what Dr. Bergin suggests: “Let those knees drop slightly apart,” with your left leg pointing toward 11:00 and your right at 1:00. Then, take it a step further: Keep your knees in these directions while you stand up and sit down, too. “Don’t allow them to collapse into that knock-kneed position again,” she says, “and keep your feet flat on the ground.”
It might take practice, but try S.L.A.M. at your desk and see if it cuts down on any of your leg and lower back pain. And don’t ignore your desk setup: here’s how to set up your workspace for better posture.
Park Y, and Bae Y. Comparison of postures according to sitting time with the leg crossed. J Phys Ther Sci. 2014 Nov;26(11):1749-52.