Fitness fads tend to come and go, but one exercise trend that seems to have stood the test of time is yoga. This ancient technique has its fair share of high-profile supporters Madonna and Gerri Halliwell to name but two although yoga is definitely not just a celebrity exercise craze.

People of all ages are attracted to yoga's holistic approach. The Sanskrit word yoga' means union' a description of the philosophy which aims to strengthen the mind, body and spirit.

Yoga comes in several styles, all of which involve asanas', the poses that help to strengthen muscles, improve posture and encourage flexibility.

Despite the popular view of incredibly bendy people with their legs behind their ears, asanas are not intended to have people tying themselves in knots. Instead, they are all about stability, balance and relaxation.

Some styles, such as astanga, are high-energy, fast-paced and powerful, so not generally suited to the beginner. Others, such as Iyengar yoga, are more meditative, with poses that are held for longer, focusing on precision and symmetry.

Other styles combine the different postures with external influences, as with Bikram yoga, where poses are carried out in a temperature of 40C, or rope yoga, which uses a system of ropes and pulleys to create resistance.

But by far the most widely taught form in western cultures is hatha yoga.

In fact, hatha' is a generic term used to describe any physical form of yoga, but in practice, it tends to describe the system of simple poses and gentle, flowing movements that make a great starting point for beginners. Hatha yoga helps to stretch and flex the body whilst developing an awareness of breath and relaxation.

People who want to find out more, as well as yoga devotees, might wish to visit this year's Yoga Show at Olympia, from September 16 to 18.

All of London's premier yoga centres will be joining the show, giving visitors the chance to take part in workshops and enjoy demonstrations. Now in its second year, the show also focuses on holistic treatments and foods.

For more information about the event, visit the web site at www.theyogashow.co.uk