Breathing Techniques
Various breathing techniques have been purported to help control asthma symptoms. One in particular, called Buteyko Breathing Technique (BBT), gained popularity in the 1950s and '60s.
In 1952, Dr. Buteyko theorized that "hidden" hyperventilation caused asthma symptoms.
Four published clinical trials and two conference abstracts have evaluated BBT.
All have reported improvements in one or more outcome measures, but results are inconsistent.
A systematic review of various breathing techniques concludes that "no reliable conclusions can currently be drawn concerning the use of breathing exercises for asthma in clinical practice" (Holloway 2004).