BACKGROUND: The limbe is a traditional Mongolian instrument that has been used since the ancient times, and the performer uses a unique method called circular breathing to play it. The circular breathing technique is significant heritage of the Mongolian people, and has been recognized by UNESCO World Heritage. Aim: To study the anatomy and physiology that take part in playing the Mongolian limbe with the circular breathing technique. METHODS: We have studied 20 flutists using case control study method. The flutists’ change of gas compound in blood have been studied with a gas analyzer after playing for 10 minutes with the circular breathing. When the flutists play it with circular breathing, the anatomical structures and their function have been studied and documented by an endoscopy, X-ray and a 320 row area detector CT. RESULTS: The 20 participants were between the ages of 22-56 with the circular breathing experience of 2 to 37 years. After playing the instrument for 10 minutes, we found the following results: 67.7% of the participants developed alkolosis, 23.5% hypocapnia, 5.9% hypercapnia, 94.1% hypoxia, and all participants’ oxygen saturation decreased. The lingual muscles, upper and under muscles of the hyoid bone, larynx and vocal cords are the main structures of the circular breathing. CONCLUSION: Playing Mongolian limbe with the circular breathing leads to hypoxia, thus the circular breathing stops. It is important to note that this process does not depend on flutist’s age, their practice time, and their personal technique. However, we concluded that the time of performance without interruption depends on individual’s physiological characteristics. In order to study the issues of anatomy and physiology that take part in playing the Mongolian limbe with the circular breathing, we have studied 20 flutists using case control study method. The flutists’ change of gas compound in blood have been studied with a gas analyzer after playing 10 minutes by the circular breathing. When the flutists play it with circular breathing, the anatomical structures and their function have been studied and documented by an endoscopy and X-ray. The lingual muscles, upper and under muscles of the hyoid bone, larynx and vocal cords take part in the circular breathing by limbe as a main rule. Playing Mongolian limbe with the circular breathing lead to hypoxia thus the circular breathing stops. This process does not depend on flutist’s age, their practice time, and their private technique. But we concluded that how long time they play it without interruption depends on individual’s physiological singularity.

Introduction: Khuumii (throat singing) is a unique form of art derived from the nomadic population of Central Asia, producing two or more “simultaneous” sounds and melodies through the organ of speech. Material and Methods: The aim of the study is to identify the anatomical structures involved in the formation of khuumii and the features and patterns of their functions and compare each type of khuumii as performed by Mongolian people. A total of 60 participants aged 18-60 years (54 men and 6 women) were selected by non-random sampling method using cross-sectional study. Statistical analysis was performed using SPSS 23 software using questionnaires, X-ray, endoscopy, sound research method, and general blood tests. Results: 90.7% of the khuumii singers were male and 9.3% were female. The average height of the participants was 172.91±0.93 cm (arithmetic mean and mean error), average body weight was 77.53±2.46 kg, and body mass index was 25.93±5.31 respectively. Heart rate was 92.19±20.71 per minute prior to khuumii while 133.19±19.09 after performing khuumii and 85.81-98.56 at 95% confidence interval. In terms of ethnicity (ethnographically), the Khalkh were the largest ethnic group (72.1%), followed by Bayad, Buryatia, Darkhad, Torguud, and Oirat (2.3%), respectively. 60.5% of the participants were professional khuumii singers who graduated from relevant universities and colleges. The process of Khuumii was recorded by X-ray examination, and laryngeal endoscopy evaluated the movement of true and false vocal chords, interstitial volume, movements of epiglottis and arytenoid cartilage, and mucosa. Khuumii increases the workload of the cardiovascular system by 70-80%. Furthermore, the sound frequency is 2-4 times higher than that of normal speech, and sound volume is 0.5-1 times higher. 95.3% of throat singers did not have a sore throat, 88.4% did not experience heavy breathing, and 74.1% had no hoarseness. During the formation of khuumii sound, thoracic cavity, diaphragm, and lungs regulate the intensity of the air reaching the vocal folds, exert pressure on the airways and vibrate the sound waves through air flows passing through the larynx and vocal folds. Mouth-nose cavity as well as pharynx are responsible for echoing the sound. Conclusion It is appropriate to divide khuumii into two main types according to structural and functional changes in the organs involved; shakhaa and kharkhiraa. Khuumii, the “Human music” originating from the people of Altai Khangai basin by imitating the sounds of nature with their own voice in ancient times, spread all over the world from Mongolia and it is proposed to classify khuumii into two main types of shakhaa and kharkhiraa in terms of structural involvement and functionality.