Myth: You can get rid of knots or scar tissue with foam rolling or massage.

Truth: “You probably hear of ‘breaking up fascia’ and ‘breaking up scar tissue,’ but the reality is that it literally takes 200 tons to deform scar tissue or cause mechanic changes to the fascia,” says Los Angeles–based physical therapist Jen Esquer, D.P.T., creator of the Mobility Method program. So whenever you’ve been told that someone is “massaging out a knot” in your back, or that foam rolling is “realigning your muscle fibers,” it’s a load of B.S. (You’ve probably also heard that foam rolling can get rid of cellulite.)

“Think: If you bump into something super hard, yeah, you might bruise, but you’re not actually breaking something in your body or tearing tissue,” says Esquer. “So why would we think that lying or rolling around on a foam roller for a while would have that extreme effect?”

You might be thinking, “But it totally helps!” You’re not wrong—it does. It just helps for a different reason: “Really, foam rolling and massage work by bombarding the brain with safe, feel-good information, convincing the muscle to relax and let go,” says Ardoin. That calming of the nervous system results in the release of tension and tightness that you feel.

And since it’s all about relaxation, you should never be trying to create pain in the body, says Esquer: “You don’t want to fire anything back up and make it potentially worse. It always comes back to relaxation.”