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 more breaths in difficult postures. Various influential figures have discussed the specific process of breath in ashtanga. Pattabhi Jois recommends breathing fully and deeply with the mouth closed, although does not specifically refer to Ujjayi breathing. However, Manju Jois does and refers to breathing called "‘dirgha rechaka puraka’, meaning long, deep, slow exhalations and inhalations. It should be dirgha... long, and like music. The sound is very important. You have to do the Ujjayi pranayama". In late 2011, Sharath Jois, the grandson of Pattabhi Jois, declared his feelings on the issue, stating that Ujjayi breathing was not done in the