[Photo/China Daily]

While Zhang's experience is extreme, it is true that yoga injuries happen more often and more easily than people think.

Cheng says students may easily strain, sprain and dislocate muscles, joints and ligaments if they don't perform exercises correctly.

Most yoga injuries are light, such as muscle strain, but there are also chronic and severe injuries accumulated over months or years because of incorrect posture. This may include injury to the cervical vertebra and spine damage, or retinal tears.

"Every asana, or yoga pose, has its mechanism and essential requirements," Cheng says.

"If students fail to get correct instruction, or if they don't follow the instructions, chances are they will end up with injuries.

"A good yoga teacher must be able to help students do the poses correctly, and not push them beyond their capabilities."

The teacher also needs to be able to detect the "danger zone" for individual learners, based on the individual's physical condition, Cheng adds.

The problem is many yoga instructors in China are not properly qualified.

Some rush into the profession only for the money, and may not have proper understanding and skills for yoga coaching, Cheng observes.

"These yoga teachers are very irresponsible," Cheng says.

Tang Xiaodi, 26, from Shanghai, has practiced yoga for nearly 10 years, and has never been injured from doing yoga.

She was surprised to hear her mother say that she hurt herself soon after taking up yoga.

Dong Hua, 54, joined a yoga class last year at a newly opened fitness center in her community in Dalian, Liaoning province.

The class had about 30 to 40 students, mostly middle-aged women. The teachers encouraged them all to adopt classic asana again and again, including headstands, shoulder stands, and downward-facing dog, in which the body forms an inverted V.

One day Dong felt a sharp pain in her shoulder while doing a headstand. The pain persisted and she decided to call her daughter, Tang.

"I was shocked to hear that her teachers had asked her to copy their stances, and that her fellow students had urged each other on.

"This was utterly different from what my yoga instructors teach me, that you do the asana as much as you can, but do not do it with ego or obsession, and do not strain yourself," Tang says.

In the end, Dong stopped her yoga classes for two months until her pain went away.

Zhou Qinlu, the fitness expert, says to avoid yoga injuries, the most important thing is to listen to your own body, not the teacher.

"Yoga is good, but your yoga teacher may not necessarily be good," Zhou says. "There is no government-authorized yoga instructor assessment system in China, and for novice learners, sudden high-intensity yoga exercise without good direction will definitely invite injury.

"When your body does not feel right, there will be signals, such as muscle twitches, spasms and sharp pain. Listen to your body and stop immediately. Otherwise, you will get hurt."

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