Every day, in New York and Paris, Tokyo and Houston, students grab towels, bottled water and rubber mats and enter a very hot room. As the teacher calls out instructions, they sweat profusely, performing a sequence of 26 postures, repeated in every 90-minute class.
Bikram or "hot" yoga took root three decades ago. The Bikram Yoga College of India in Los Angeles, named for its founder, Bikram Choudhury, has 314 certified schools worldwide. More and more people are taking up Bikram to lose weight.
However, medical professionals are expressing concerns about the demands of contortions performed in extreme heat. "Heat allows you to stretch more," said Robert Gotlin, director of orthopedic and sports rehabilitation at Beth Israel Medical Center. "But once you stretch a muscle beyond 25% of its resting length, you begin to damage a muscle," inform timesofindia.com
Bikram advocates maintain that the immediate warmth and simple movements at the start of each class are safer than traditional yoga. "The heat helps people work slowly and safely into the postures and makes injuries infrequent," said Jennifer Lobo, an owner of Bikram Yoga NYC.
But David Bauer, a physical therapist in New York who also teaches yoga, said the enthusiasm and competition among participants could contribute to injuries.
"When you are in a hot studio filled with hard-core Type A personalities, and everyone's adrenaline and endorphins are pumping, you're not feeling any pain," he said, "and it may mask how far you can go."
The mirrored walls in Bikram studios may encourage students to concentrate on outward form, Mr. Bauer said. In contrast, more traditional yoga emphasizes an inward focus on breathing and individual limitations, possibly helping to curb injuries.
Indeed, part of the Bikram yoga philosophy is the push to go a little farther every time a posture is performed. Each pose is done two times per class. Participants arch backward and bend to the side in "the half-moon pose," for example, and then do the movement again, trying to bend the spine even more.
Practitioners maintain that the spinal flexibility and strength cultivated in Bikram yoga can be vital in warding off the effect of aging on posture. Some physical therapists, however, question the value of excessive joint flexibility, saying it can lead to inflammation and pain.
"The extreme range of motion yoga develops does not necessarily have an advantage, and it may be counterproductive," said Dr. Shirley Sahrmann, a professor of physical therapy at the Washington University School of Medicine in St. Louis. Like dancers, practitioners of yoga cultivate overly flexible spines, which often cause problems in resting posture, report nytimes.com