If a friend ever asks you to crack their back for them, don’t do it! Physical therapy professor Dr. Greg Kawchuk says unless you’re a chiropractor, you risk using too much force, which could damage ligaments or disks. But if you crack your OWN back by twisting your torso to get a satisfying “crack,” that’s OK! Dr. Kawchuk says people usually do it because of stiffness or pressure, and it does provide relief by moving joint surfaces away from each other. And just like cracking your knuckles, even regularly twisting your torso typically won’t cause lasting problems, including arthritis or lingering pain.