The low-down

Bikram Yoga is the creation of Bikram Choudhury (b. 1946), who began studying asana at the age of three. At 20 (so the story goes) he was badly injured in a weightlifting accident and despite a grim prognosis from the doctors, managed a full recovery with the help of yoga. Since the 1970s, Choudhury has built a worldwide yoga empire, and courted more than a little controversery, with his sequence of postures performed in a heated room.

There are lots of breakaway studios teaching 'hot yoga' these days, but Bikram Yoga is the only style which comes with the guru's guarantee. Choudhury works hard to protect the Bikram Yoga brand; all teachers and studios are centrally monitored which means that attending a Bikram class is a remarkably consistent experience, whether you're in Hong Kong or Hull.

What happens in class?

The first thing you'll notice is the heat: Bikram studios are kept at a temperature of around 40ºC/105ºF. You will sweat a lot throughout the 90-minute class. Bring a full-size towel to put on top of your mat, unless you are really comfortable rolling around in a soup of sweat, and a large bottle of water, unless you are a camel. Bikram teachers are taught to recite a set script, and the 26 postures and two breathing practices are always offered in the same sequence, so classes are highly predictable and it's easy to measure your progress from week to week.

If you're used to practising yoga at normal room temperature, you may be surprised how much further you can stretch in the super-heated Bikram studio – but you'll need to listen to your body carefully, as it is possible to push joints and ligaments too far when you're hot.

The teacher will generally give instructions from a podium at the front of the class; don't expect individual attention or adjustment, and be prepared to take responsibility for your own practice. The hot, sweaty classes can bring out people's exhibitionist tendencies; mirrored studio walls reflect skimpy outfits and correspondingly large amounts of flesh.

Studios recommend a fairly intensive immersion to get you started, and many offer an introductory price for unlimited classes during a 20- or 30-day period.

Who goes?

People who like to sweat! It's common sense, really. Hot yoga is really big with bankers and other stressed professionals. One of them told me that he goes for the hit of pure oblivion: the physical experience is so completely involving that it wipes out all other thought.

Some people with muscular-skeletal injuries swear by Bikram yoga, because the heat promotes pain-free stretching and flexibility, and the predictable posture sequence makes it easy to learn and remember modifications to the postures that suit their physical limitations.

Who should avoid it?

My own completely unscientific, anecdotal research suggests that pale, freckly Northern European types who generally avoid sun and saunas don't tend to get along with hot yoga. If you come from a yoga background that emphasises breathing and contemplation, you may find the stifling heat of the studio a frustrating and distracting experience at first.

Overheating (hyperthermia, heat stroke) is a possibility during any hot yoga class, though adequate hydration and resting when necessary should protect most healthy adults. More seriously, students with conditions including MS, epilepsy and some heart conditions should not attempt to practice in 40ºC heat. Some medications for depression, anxiety and insomnia also increase sensitivity to the effects of high temperatures, check with your doctor if you're in any doubt.

NHS guidelines advise pregnant women to avoid exercising in high heat, particularly during the first trimester when it may affect foetal development. Women who already have a well-established Bikram practice may choose to continue (with modifications and at their own risk), but you should definitely not start doing Bikram yoga for the first time if you are pregnant or trying to conceive.

What will it do for me?

Bikram yoga can promote significant weight loss – but be aware that the initial results are almost all down to fluid loss.

As with all forms of yoga, regular practice usually brings increased strength and flexibility, a more sculpted body and better posture and balance. Students also report feeling 'detoxified' by the heat and sweat, and emotionally calmer and happier.

Finding a teacher

As previously noted, the Bikram yoga brand is closely monitored– any studio which advertises Bikram yoga will offer a similar experience, though quality of facilities will vary. Bikram teachers all undertake a nine-week intensive training course with Choudhury and his senior teaching staff, at a cost of $11,400. You're therefore unlikely to find a Bikram teacher who is not very serious about their job. Other hot yoga studios offer their own versions of the Bikram approach, and are therefore less predictable.

In recent years, Bikram Choudhury has been dogged by controversy. His efforts to promote yoga as a competitive sport and to copyright traditional yoga postures have made him unpopular with some sections of the wider yoga community. More seriously, in the course of 2013 five different women filed civil suits against Choudhury in the US, alleging sexual assault, harassment or discrimination. Partly in response to this damaging publicity, a number of Bikram studios have dropped the brand and started offering “hot yoga" instead – a trend that seems likely to continue.

Further reading

Bikram's Beginning Yoga Class

Bikram Choudhury with Bonnie Jones Reynolds

Hell-Bent: Obsession, Pain and the Search for Something Like Transcendence in Bikram Yoga

Benjamin Lorr