Evidence for yoga's health benefits is growing, with research showing it can help manage stress and reduce lower back pain. It might even cool the heat during menopause. One small American study reported an average 30 per cent reduction in hot flushes after eight weeks of yoga.
There is more than one kind of yoga but, for those who don't know their iyengar from their ashtanga, how to tell which class to take?
''The first thing to decide is what you want from a class,'' says the vice-president of Yoga Australia, Leigh Blashki. ''Do you want to relax and restore energy or do you want something more vigorous?
''Yoga is about balance. If your life is hectic, you might need a slower class. If you're sitting down a lot, maybe you need something more vigorous.''
The more energetic yoga styles (which often attract more men) include ashtanga, power yoga and iyengar, although iyengar can have periods of stillness as well. Vinyasa yoga can also be faster paced because the different postures (or, in yoga speak, ''asanas'') flow dynamically from one to the next. More meditative styles include raj, siddha and turiya yoga.
That said, yoga techniques are hard to pigeonhole because of a trend for teachers to use a fusion of styles.
''After a teacher has practised yoga for a while, they see what they like best about different styles and then put them all together,'' says Blashki. ''This … means yoga keeps adapting, rather than sticking with what a particular swami might have been teaching in 1920 and which may not be relevant now. If you're looking for a class to suit you, rather than asking a teacher, 'What style do you teach?,' it's best to ask what they emphasise in a class … Is it breathing, strength or flexibility?
''The most important thing is finding the right teacher - someone you relate to, someone who's professionally trained, who keeps up with professional development and has professional risk insurance.''
Yoga won't burn many kilojoules or do much for cardiovascular endurance the way walking, jogging or cycling will, but it is great for improving flexibility and range of motion, Rob Newton, a professor of exercise and sports science at Edith Cowan University in Perth, says. ''Both the static and dynamic postures of yoga are very good for balance,'' he says. ''You'll also get some increase in strength with any postures that involve supporting your own body weight - like the plank, downward facing dog or squatting - although if you really want to build strength, you need to use weights.''
The best approach is to mix activities that improve cardiovascular fitness, strength and flexibility. But, Newton says, yoga's ''mindfulness aspect'' is important. ''Focusing on your body and your breathing quietens the mind and helps with anxiety,'' he says.
Neither Blashki nor Newton is a fan of bikram yoga, which is practised in heated studios sometimes as hot as 40 degrees. Despite claims that heat increases yoga's benefits, Newton says such conditions are more likely to impair physical performance.
''The body diverts blood away from the muscle to the skin to try and keep your core temperature from rising,'' he says. ''Exercising in heat can place unaccustomed stress on the heart as the cardiovascular system tries to balance the demands of cooling and exercise, so there's a real risk of problems if someone has pre-existing cardiovascular disease. Without proper management and monitoring, there's the risk of heat illness or even death.''
To find a yoga teacher who is registered with Yoga Australia, see yogaaustralia.org.au or phone 1300 881 451.
Paula Goodyer blogs at smh.com.au/chewonthis.
