What Even Is Your IT Band & Why Does It Hurt So Badly?

If you're a runner, walker, biker, dancer, or any type of person who moves, there's a good chance your iliotibial band (a.k.a. your IT band) could use some love. Your IT band is a band of connective tissue that runs from the top of your hip to the outside of your knee, like where a tuxedo stripe on the side of your pants would be, says Jill Miller, creator of the corrective exercise format Yoga Tune Up and author of The Roll Model Method. While you can't see your IT band just by looking at your leg, you can definitely feel it if you run your hand down the outside of your hip and move down your thigh to the outside of your knee. (It might feel tender or actually hurt to touch it.)

The IT band is responsible for keeping your knees and hips stable, and it helps your legs move when you walk and run. "The IT band is commonly mistaken as a muscle, but this is a popular misconception," says Kevin McLaughlin, a physical therapist at Johns Hopkins University. The tissue connects your tensor fascia latae (a muscle in your thigh) and gluteus maximus (your butt muscle) to the tibia (your shin) just below the knee joint, McLaughlin says. In other words, your IT band is very well-connected, which means it can wreak havoc when it gets screwed up.

For example, if your knee tends to hurt during or after a run or walk, your IT band might be responsible. When your IT band is overworked or tight, it literally rubs on your femur and gets inflamed, which causes pain on the outside of your knee. This is commonly referred to as "IT band syndrome," McLaughlin says, and it's the most common running injury (up to 12% of runners have it). A tight IT band can also contribute to bursitis in your hip, which is another running injury, McLaughlin says. Part of the IT band's job is to keep your knee in line as you move, so if you have a wonky gait (like you run with your feet slightly turned out or you pronate) or tend to do workouts that require a lot of leg stability (like dance or soccer), that can make your IT band tight and inflamed, too.

So how can you tell if your own IT band is a little stressed? "If your IT band is inflamed, it will impact your comfort when bending the knee, especially going up or down stairs," Miller says. To diagnose IT band syndrome, physical therapists usually bend your knee at a 90- to 45-degree angle. If you have IT band syndrome, this motion could hurt a lot, but that's not necessarily a reason to panic. "It’s important to remember that neither of these [IT band] conditions are especially serious, and [they] respond well to physical therapy," he says. Also, keep in mind that even people who don't have IT band syndrome can still feel pain around their knees because their IT band is just tight.

Stretching your IT band can help, but McLaughlin says it's more important to stretch all the muscles surrounding it, like your quadriceps, hamstrings, hip flexors, and hip rotators. "The IT band is not a muscle and therefore won't respond much to attempts at stretching it," he says. Your IT band is strong, and McLaughlin says it's been compared to construction-grade steel in terms of tenseness and strength. "With that in mind, it's more prudent to work on stretching the muscles that attach to your IT band," he says.

Here's one easy IT band stretch you can try almost anywhere: Cross one leg over the other at the ankle, then extend the arm of the front leg overhead until you feel a stretch on that corresponding hip. If you don't feel much from that, you can try lying on your back and looping a yoga strap or belt around one of your feet. Keeping your knee straight, gently bring your foot across the midline of your body; you should feel an intense burning or stretch on the outside of your lifted foot. Physical therapists often recommend foam rolling your IT band — but again, you'd also have to foam roll the surrounding and connecting muscles in order to properly treat an IT band issue.

"Typically, if the IT band is inflamed, the muscles connecting to it are in even worse shape from overuse or injury," Miller says. "The health of those muscles should be addressed first before the IT band is 'blamed' for feeling gunky." It's kind of like a chicken-or-egg issue: If you have a tight IT band, then the muscles around it will become imbalanced, and your IT band becomes even more irritated, which causes strain on both the muscles and the IT band, Miller says. "If the muscles connecting the IT band are chronically imbalanced, they will likely create imbalances in the other muscles that are a part of the IT band’s domain," she says.

The good news? Having a balanced exercise routine that involves stretching and some recovery routine, like yoga or self-myofascial release, will help strengthen and mobilize your joints and tissues so that you can hopefully avoid pain, Miller says. "Your IT band is happiest when the muscles it attaches to are happy," she says. Just remember: Stretching can be a literal pain in your butt, particularly if you're stretching your IT band, but the hurt can be totally worth it.