A few months ago, I was taking a yoga class with a new teacher. I thought my ability to touch the floor with my palms flat or easily sink into triangle pose was just a reflection of how far I’d come in my practice. I was wrong. As I shifted my body into triangle pose, she stopped the class.

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“OK, one thing I don’t like,” she said, “is when people hyperextend. You need to engage your muscles. Put a tiny bend in your knees.” I did. My legs were on fire. The pose went from being passive — little more than a side stretch — to an active leg workout.

For the rest of the class, she instructed us to make the same adjustments. Where I’d previously locked my legs, I loosened them with a microbend instead. My legs were sore all weekend. I’d spent months practicing, but I’d never used my legs so intensely before.

So I got to Googling (as you do).

It turns out she was right, especially for me. In several of my joints, I’m hypermobile, which means that my joints allow me to move beyond a normal range of motion. I had a pretty solid score on the Beighton Scale, which measures hypermobility, suggesting that my range of motion might even be a genetic defect — a surprisingly common one in fact. I realized in many asanas, I was letting my joints bear the brunt of the pose rather than my muscles. In standing poses, I locked my knees until they tilted slightly inward. In downward dog, I locked my arms and let my weight slide into my shoulder blades rather than engaging my triceps. When my teacher corrected me, the pose went from feeling like a light back bend to a pushup.

I felt like I’d been betrayed. I’d thought yoga was one place where I could only do good for my body. Unfortunately, that’s not the case. If you get beyond the beautiful Instagram photos and uplifting quotes, there is a big conversation happening in the yoga community about injuries. Dedicated yogis are reporting thrown-out backs, torn rotator cuffs, bulging disks and even strokes.

“Clearly, we need to have a normal and healthy range of motion in all of our joints in order to be able to function,” says Diane Bruni, a yoga teacher who is starting a conversation around traditional yoga mobility. Bruni experienced her own tremendous injury as a result of too much flexibility. A few years ago, after an hour of deep hip-opening poses, she leaned forward. Her muscles ripped clean off her hipbone.

“What’s happening right now in the yoga world is that we’re going beyond normal and healthy,” Bruni says.

Bruni invited me to join a group she started on Facebook, Yoga and Movement Research Community. There, yoga teachers and students from a variety of backgrounds are sharing what they’re learning about movement in the human body and where yoga is getting it wrong.

“My ribs kept slipping out of place for over a year,” a woman in the group shared with me. She says the injury was from repetitive twisting and binding. She shared a graphic photo of acupuncture needles in her left rib. She’s stopped telling her yoga students to twist or bind in poses.

“If I don’t balance my practice, my low back, particularly my [sacroiliac] joint, will slip out of place,” another woman shared. Most recently, she’d attended two yin yoga classes — typically, a class of deep stretching poses that are held for several minutes — and the next day, her sacroiliac joint slipped, requiring a trip to the chiropractor, including activator adjustments, acupuncture, laser treatments and electrical stimulation. “This was a reminder that, once again, I need a balanced practice focused on strengthening… but oh, I love to stretch!”

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Bruni has a particular bone to pick with yin classes, which emphasize stretching poses. She says that students often tell her they find the classes relaxing, which is exactly the problem: The classes don’t offer an opportunity to build strength to counterbalance the stretching.

Not to mention, too many students who don’t need additional flexibility are taking the classes. Bruni uses pigeon pose as an example — shin parallel to the front of the mat, hips on the floor and level. In a yin class, you might stay there for five to 10 minutes. “There’s absolutely, in my opinion, no good reason to do that over and over again to your body. You don’t need the flexibility. You’ve already got it. And you’re just weakening your joints by hanging out in those poses.”

And Bruni believes many of these injuries relate back to hypermobility like mine.

“The whole thing about yoga superstar teachers is they’re mostly hypermobile,” she says. “And hypermobility is not something we should be encouraging.” She talks about legs behind your head, for example, which used to be viewed as an extreme contortionist pose. Now it’s commonplace because naturally hypermobile people are finding a yoga practice and being encouraged to go as far as possible.

But these advanced practices come with a risk. “Hypermobility causes pain and causes problems,” Bruni says. “So many people are hypermobile. They’re overstretching. They’re creating more inflammation and instability in their joints. They’re in pain, but the crazy thing is, they think more yoga is going to help them.”

Still, she’s not suggesting we should all be rolling up our yoga mats forever. “Do yoga once or twice a week,” she says. “It’s plenty. Then do your other activities. Cycle, run, walk, go to the gym, swim, go to a dance class, move, do different things. And then your body will likely be less prone to injury doing any of those things. The majority of injuries happen because we do one thing too much.”

Sorry, yogis. It looks like we might need to join the gym after all.

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