All that extreme bending could cause some serious injuries in even fit and healthy people, including damaging your hip joints, nerves, knees, and back.

In response to the article, health website MyHealthNewsDaily published a tip sheet last week on how to avoid needless injuries the next time you unroll your yoga mat.

When it comes to forward bending, Uttanasana or other postures can spell trouble if you suffer from osteoporosis.

Dr Loren Fishman, a New York City physician who is also a yoga instructor, told MyHealthNewsDaily that those with the disease could "fracture their spines by bending forward, and those with herniated disks may suffer pain from these stretches."

Backbends can also serve up trouble for some. If you have a herniated disk, Fishman green lights yoga, saying it is "a known physical therapy technique." However, if you have spinal stenosis, a narrowing of the spinal column that causes pressure on the spinal cord, backbends can exacerbate the condition.

Also, while standing on your head seems to be the path to yogic enlightenment, inversions aren't for everyone. "The advantages of any inverted pose are terrific," Fishman said, including strengthening "the diaphragm, helping people with asthma, emphysema and bronchitis, and bring[ing] blood to the upper lung fields, places that are under-infused with blood."

But if you have neck or back problems, glaucoma, or cerebro-vascular problems, avoid headstands. And those with neck problems, herniated disks, or bad arthritis should skip shoulder stands, Fishman said.

Twisting poses can "stretch the back and hips, massage the abdominal organs, and increase blood flow to the spine," notes MyHealthNews. But skip the twists if you've had hip replacement operations. However, contrary to common thought, Fishman believes that those with osteoporosis can twist without complications or harm.

Also, yoga in heated rooms, such as Bikram yoga, boasts health and fat-burning benefits, but clearly this strenuous style isn't for everyone, especially for people with serious health problems.

For instance, people with multiple sclerosis (MS) should avoid it altogether because heat can worsen the condition, warns Fishman. A safer yogic option? Try Iyengar yoga, as it focuses on alignment and avoiding injury through the use of supportive props.