Is yoga actually bad for you?
Madonna and Sting are fans, Roy Keane's done it and even the Leinster rugby team have given it a go. Once seen as the domain of cheesecloth-wearing hippies, yoga is now the discipline of choice for anyone who wants to improve strength, balance and mental well-being.
With the wealth of studios, gym-based classes as well as lessons in schools and church halls, it's impossible to judge just how many people in Ireland practise yoga, but a conservative estimate puts Irish yogis in the tens of thousands.
Put it this way: less than 10 years ago there were just three or four yoga studios in the greater Dublin area -- now there are 50.
Aficionados are quick to praise it for curing bad backs, improving posture or helping them unwind after a stressful day's work.
Celebrities love it. Gwyneth Paltrow, who practises six days a week, says: "Yoga has completely changed me. . . the effect is amazing," while Jennifer Aniston, who does it an hour a day, gushes: "It's a therapy session, a workout and a meditation all at the same time."
But recent studies suggest that yoga might not be the panacea so many hail it as.
Scientists at the University of York discovered several people, in a trial to see if yoga alleviated back pain, actually reported being in more pain after the classes, while a second investigation, carried out a week earlier in the US, found that doing yoga postures carried no more health benefits than doing simple stretches.
Dr Karen Sherman, an epidemiologist at the Group Health Research Institute in Seattle, who led the study, says: "We found yoga classes more effective than a self-care book -- but no more effective than stretching classes." She added that the breathing associated with yoga didn't appear to have any impact.
Understandably the results have not gone down well with yogis. "Anecdotally all I can say is that one of the most common pieces of feedback I get from people who suffer from back pain is that doing yoga gets rid of the pain," says yoga teacher of 10 years Pauline McCarthy who runs Exhale Yoga Studio in Sandymount. She adds: "The second most common response is that students feel so calm they experience the best night's sleep after a class."
Colm Walsh is the director of Yoga Dublin (yogadublin. com) and has been practising its techniques for some 20 years. He says he knows first-hand that yoga can heal.
He says: "Yoga cured my bad back. I was in extreme pain, went to a physio who recommended yoga and within six months to a year the pain was gone and never came back."
He adds: "You can pick holes in any exercise. I see people all the time with injuries and tight muscles from running but at the end of the day is it not better to be doing something than doing nothing?"
But there are other issues of concern. From its meditative Indian roots, yoga has been transformed for the 21st century. It now boasts it own fashion ranges and more intense versions set in heated gyms. From Madonna contorting herself into pretzel shapes for her stage shows and Lady Gaga announcing "I'm kicking ass in yoga" the discipline, for some, has become increasingly extreme, competitive and, as a result, prone to injuries.
"I'm seeing a lot more yoga-related injuries coming through," says chartered physiotherapist Frances Moran from Bodyworks Physio, Baggot St, Dublin.
"In the past fortnight alone I've had three. It's still small numbers compared to rugby or football, but they're definitely on the increase."
Typically, the injuries are of the neck and lower back from overstretching or bruised cartilage in the hips and damaged knees. "Yoga is a super form of exercise but how beneficial it is depends on what type you're doing, who is teaching it and what class numbers are like," says Moran. "Particularly in Bikram yoga, which involves stretching in hot temperatures: it's easy for people to push themselves too far without realising it."
Moran isn't convinced that anyone needs to strive to stretch themselves into the sort of shapes Madonna achieves.
"As a physio I would question how much flexibility we really need. Yes, you want to be supple but the body isn't designed for us to have our legs behind our heads and there can be problems associated with being too flexible.
"I have several clients who did a lot of yoga for years and stopped only to develop a lot of aches and pains a few months later. Basically their bodies had adapted to that level of flexibility and needed it to hold it together."
There's also a concern that injuries could be linked to larger classes and poor teaching.
"Personally I would never have more than 12 in a class," says teacher Pauline McCarthy. "That way I can monitor what everyone's doing. I also make sure I know if anyone has injuries or health complaints."
Walsh agrees: "Who's teaching yoga is a matter for concern. There are a lot of new teachers coming into yoga and one of the problems is that there's no one universally acknowledged qualification. There's nothing to stop someone setting up a studio and inviting people in off the street to a general level class, it's up to the student to use a bit of intuition."
Walsh's advice is for any would-be yoga devotees to read up on the form of yoga they want to do and research teachers before signing up to anything. He says: "There's a form of yoga out there that's suitable for everyone and with the correct supervision and by building up gradually, there is no need for anyone to injure themselves."