"Our findings suggest that yoga exercise may lead to small improvements in asthma quality of life and symptoms," said lead author Zuyao Yang from Chinese University of Hong Kong.
The study, published in the journal Cochrane Database of Systematic Reviews, involved 15 randomised controlled trials which involved 1,048 men and women. Most of the trials were conducted in India, followed by Europe and the US.
The majority of participants had mild to moderate asthma for six months to more than 23 years. Six studies looked into the effects of breathing alone during yoga exercise, while the other studies assessed the effects of yoga that included breathing, posture and meditation.
Most people continued to take their usual asthma medication while participating in the studies. The studies were conducted over a time period of two weeks to over four years. The researchers found some moderate quality evidence from five studies that yoga exercise reduces the impact of asthma on people's quality of life.
"However, it is unclear whether yoga has a consistent impact on lung function and we don't yet know if yoga can reduce people's medication usage, or if there are any side-effects of yoga for people with asthma," Yang noted.