His breathing training operation can detect the user's heart rate change in real time during breathing training, make a score, and give reasonable suggestions for improvement after each breathing training. Breathing training especially emphasizes real-time feedback and monitoring whether breathing correctly drives some changes in heartbeat rhythm, which is similar to breathing in traditional Chinese medicine and pranayama in western medicine. Breathing training is a traditional pranayama training in China, which has been recognized by the World Health Organization and spread all over the world. It is a very effective and simple exercise method.