Bikram Yoga founded Bikram's Yoga College of India. He has also written books and sings. As of 2006, he had 1,650 yoga studios around the world. In 2012, there were 330 studios in the United States and 600 worldwide. A 2013 review of adverse effects from yoga found that Pranayama and Bikram were the most commonly cited styles, and found harm arising mostly in instructors who practiced intensely over a long period of time and who used advanced positions like handstands; in Bikram most of the adverse events arose from the heat and included low salt levels due to excessive water drinking
Ashtanga vinyasa yoga asana practice, but also stated that the breathing should be deep breathing with sound. He reiterated this notion in a conference in 2013 stating, "You do normal breath, inhalation and exhalation with sound. Ujjayi breath is a type of prāṇāyāma. This is just normal breath with free flow". In 2014 published on YouTube, Manju Jois dodged the question, "What is the difference between Ujjayi breathing and free breathing?" by saying that "the breathing in Ashtanga should be long and deep with the sound like the ocean". He also states that if you don't make sound, that is okay, too. However