If you’ve ever been in the middle of a workout and noticed that your hips are popping, chances are you’ve been hesitant to power through. Whether you’ve attempted to adjust your movement or skip the offending exercise entirely (leg raises, leg circles, bicycle crunches, and side plank crunches are all common culprits), it doesn’t solve the multi-part mystery of what’s causing it in the first place or how you can keep it from happening in the future.

“No matter what the exercise method is, it’s always the same issue,” Sharyl M. Curry, a certified Pilates instructor and founder of Park East Pilates tells me when I visit her for a session in her New York City studio. “If you’re lifting the leg up and down with your thigh bone jammed up in your hip, that’s when you get the popping,” she explains. This happens when you’re not properly lengthening the leg out of the hip, she says. “You always want to be creating and maintaining space in the joint with the help of the muscles.”

Of course, there are a lot of mechanics going on behind every lift and circle of the leg, and since you won’t be successful in lengthening out of the hip if other alignment issues are in play, Well+Good turned to Curry and NYU Langone physical therapist, Naomi Bailin, DPT for an easy-to-follow understanding of why your hips are popping during a workout.

What exactly is causing my hips to pop?

According to Bailin, there are several possible culprits behind your recurring hip popping, and they’re as simple (and harmless!) as a tendon sliding over a bone to a more serious issue like a labral tear (more on the latter in a bit). But most likely, what you’re experiencing is due to tightness in the connective tissue surrounding the hip joint capsule, which is made up of ligaments that connect bone to bone. “This can result in abnormal mechanics happening in the ball and socket joint in the hip,” Bailin says.

When you’re doing an exercise, such as lying on the floor and raising your legs, Bailin explains that the hip joint should glide downward. “Instead, the joint glides up if that hip is too tight in the connective tissue that encapsulates the joint.” (That’s the “jamming” of the thigh bone Curry mentioned earlier.)

One more thing that’s important to note, both Bailin and Curry say that a weak core is often to blame for this tightness. “We have to stabilize the hip joint so that it can move freely in the socket, and we do that by keeping the torso stable,” says Curry, who adds that by properly engaging the abdominals, you’re then able to create space in the hip joint by lengthening the leg.

On the other hand, a loose body of cartilage or a labral tear can be a more serious issue that causes hip popping, but Bailin notes that it’s more common in professional athletes like gymnasts or dancers (and can often be managed without surgical intervention). “The labrum is the washer that surrounds the socket of the hip joint,” Bailin explains. “It kind of deepens the socket and makes it more stable, and when there’s a tear in there, you can get some deeper clunking and popping.”

Is it really so bad if my hips are popping?

Unless the resulting hip popping is causing you pain, Bailin assures that there’s nothing serious going on. “The popping in and of itself, you don’t have to worry about,” she says. “It’s when it starts to interfere with function—so if accompanied by pain, by limitation, by sensations of instability where the hip is wobbly and making you feel unsteady—that can mean there’s something more going on.”

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But even if it’s not causing you pain, hip popping can be an unpleasant sensation, and it is a sign that you’re not using the proper alignment during a workout. That, in turn, leads to relying on different muscles from those that the exercise intends to target, which means you won’t get the full benefits from your workout.

How can I prevent my hips from popping?

How you tackle the issue largely depends on your root cause behind the improper mechanics of the hip. Personally, Curry was quick to diagnose that because I was tucking my pelvis, it wasn’t possible for me to engage my abdominal muscles. That led to the whole domino effect of my hip flexors overcompensating to do the stabilizing work instead, causing the tightness that’s likely behind my hip popping. For general tightness in the hip, Bailin recommends stretching before your workout, suggesting kneeling lunges to target the adductors (inner thighs) and single-leg bridges to target the glutes and core (alternating sides).

If you’re suspicious that a weak core could be to blame, start by taking the time to ensure you’re properly engaging your abdominal muscles. An example, Curry says, is attempting to do leg lifts while lying on your back on the floor while not letting your back arch up off of your mat as you lower your legs. “It’s not the spinal column that has to push down, it’s the muscles that support around the spine,” she explains. “The more you pull in from the front, the more the back will roll onto the mat.”

Bailin adds that if your core isn’t yet strong enough to perform a particular exercise without your hips popping, you can try reducing the range of motion. If you’re getting popping when your legs are going low to the ground, for example, she says not to lower your legs as far down. “[This way] your spine can stay stable, rather than arching back and forth,” she advises. “By doing less, you’re then getting a better workout because you’re using the abdominals for what they’re intended for, which is to avoid spinal motion.”

When should I reach out to a professional?

If your hip popping is ever causing you pain, Bailin stresses that you should book an appointment with a physical therapist to address the issue as soon as possible. “Don’t let problems like this become chronic,” she says. “What can happen is, when you’re moving in a different way because you’re uncomfortable, then another joint can become an issue as a result of the faulty movement patterns. Don’t wait until one thing becomes two, and then two becomes three, and it becomes harder to intervene conservatively.”

For hip popping that’s not causing pain or stability issues, but just won’t seem to go away (and is a major nuisance, like mine), you can still opt to visit a physical therapist. They will be able to assess your alignment and address any issues they find—or direct you to a doctor should you need further medical intervention.