Its physical benefits for flexibility and balance, as well as its spiritual connection, mean it's practised by millions across the world.

And that means a need for more and more yoga teachers.

But now, there is a warning they may be putting their own hip health at risk.

Benoy Matthews, a leading UK-based physiotherapist, warns he is seeing increasing numbers of yoga teachers with serious hip problems - many of whom require surgery - because they are pushing their bodies too hard.

Mr Matthews, a specialist hip and knee physiotherapist and member of the Chartered Society of Physiotherapists, says he sees four to five yoga teachers a month.

He says the problem lies in people repeatedly pushing their bodies into "prescribed" positions, when their physiology prevents it.

About half of the teachers he sees simply need advice on how to moderate the "prescribed" yoga positions, so as not to put too much stress on their joints.

But those with more advanced problems need medical treatment and surgery - including total hip replacements.

"People confuse stiffness and pain," he says. "If there is a pinching or blocking feeling in the groin, it shouldn't be ignored. You have to know your limits."

Mr Matthews has specialised in hips and knees for the last eight of his 22 years as a physio.

He says it can be easy for yoga practitioners to mistake joint pain, which means they should stop the movement, for stiffness, which they should push through.

"We all know about the health benefits of yoga - I practise it myself," he says. "But, like anything, it can cause injury. We can't put it on a pedestal.

"I don't want to denounce yoga, after all it's been going for thousands of years. But you have to understand yourself."

Mr Matthews says the problem often boils down to how a person's hips are formed and how flexible they are.

"What's achievable for one might not be achievable for others," he says. "People tend to do the same set positions, rather than what's achievable for them.

"Ego might mean them trying to take a position 'all the way' to the end when they should just stop where it's comfortable.

"Just because the person next to you can reach all the way doesn't mean it's necessary, or desirable, to do the same."

BBC

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