By playing breathing games kids condition themselves to make their exhalations longer, resulting in a slower, deeper, and more efficient breathing. Breathing games are based on a breathing technique called Pursed Lip Breathing and they are designed to train kids to make exhalations longer. This is specially recommended for people with breathing related (asthma, emphysema, COPD) and stress related (anxiety, blood pressure) disorders. In general medical doctors encourage people to perform Pursed Lip Breathing in order to get more oxygen, to gain energy or to relax.
Asthma School, 2014, Mladinsko zdravilisce Debeli Rtič (link)