A total of 90 patients with predominantly moderate to severe asthma were randomly assigned 1:1 into either the exercise or control groups. After in-person training at the initial visit, the 45 patients in the exercise group performed a short 3-part breathing exercise program twice per day at home for 1 month. This intervention incorporated 3 types of breathing techniques — the yoga technique pranayama, diaphragmatic breathing, and pursed lip breathing — and was developed by a multidisciplinary team of asthma and pulmonary specialists[AL1] .

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