Hamburg  - Madonna practices yoga and so does Courtney Love. Even the German national football team swears by it.

The word yoga translates from Sanskrit into English roughly as "union with superiors" and originated in India. Through its growing popularity in the United States, it has been making a triumphant advance around the world.

The holistic exercise promises relaxation, flexibility and stability. However, anyone who would like yoga to bring their body, spirit and soul into alignment should pay attention to a few things. This begins with the selection of the right type of yoga the practitioners of which are called yogis.

"Nowadays, there are so many directions that have developed from the original Hatha yoga," said Nina Haisken of a German yoga trade magazine published in Wiggensbach, Germany. What is offered is equally confusing. The best approach is to orientate oneself on the various yoga masters after which the individual types of yoga are named. Many people like the classic Sivananda or Iyengar yoga, but new variations such as Bikram yoga are enjoying growing popularity.

All forms of yoga have in common the asanas or positions, and pranayama or breathing exercises, which yogis perform guided by a professional instructor. However, the differences between the various types of yoga in equipment and emphasis quickly become clear when looking at the details.

"Sivananda as a holistic concept comprises all components of yoga - that's posture, meditation, relaxation, breathing and nutrition," said Benita Grosser, a yoga instructor in Hamburg. The class always begins with breathing exercises and a prayer to the sun that follows 12 fixed positions.

"We start at the head and finish with the feet," said Grosser. Additionally, there is meditation and an Ayurvedic cooking course. Conversely, Iyengar yoga places considerably more emphasis on physical exercise.

"Its founder, BKS Iyengar places a lot of value on the exact execution of the individual asanas," said Corinne Trotzkowski, who operates a yoga studio in Stuttgart. The spiritual benefits occur naturally with the right body alignment. Iyengar yoga requires yogis to work with various props. Flexible bands, stools and blocks are used to support certain positions, which vary from class to class because usually one particular body part is the focus.

Bikram yoga, named after its founder Bikram Choudhury, emphasizes posture. Every class lasts 90 minutes and there are 24 positions and two breathing exercises that are always carried out in the same order in a room that is at least 38 degrees Celsius. The yogis stand for the first 60 minutes, then lower themselves onto the mat for the remainder of the time.

"The perspiration stimulates the burning of fat and the body is more expandable," said Trotzkowski. Newcomers to yoga should however consider that it's easy to overestimate what they can do. Thus, it's important to go to a serious yoga centre.

"People who instruct yoga should be able to show that they have had a sports medicine or medical education," said Trotzkowski. Students can be instructed and corrected only with comprehensive physiological and anatomical knowledge. For this reason the three experts advise against the use of DVDs and books.

"These guides for use at home can be dangerous primarily for beginners who have no experience with yoga at all," said Haisken. They should be used only as a supplement. There is no principle for when the "union with superiors" is reached. "But basically, of course, these things are better than nothing, regardless of whether it's 10 minutes daily or a weekly class." (dpa)