The purpose of this study was to examine the circulatory-respiratory dynamics in elderly people during Tai Chi Yuttari-exercise. The subjects were females with an average age of 74 years who had been continuously practicing Tai Chi Yuttari-exercise for at least six months. The heart rate and blood pressure were measured before and after the subjects performed four different versions of Tai Chi Yuttari-exercise. The perceived exertion was evaluated using the Borg scale. The respiratory rate, oxygen uptake and respiratory quotient (RQ) were measured using an expired gas analyzer. The results showed an increase in heart rate during exercise, but confirmed that the rise in HR was below the safety limit. The blood pressure tended to be low post-exercise. Regarding perceived exertion, the maximum heart-lungs Borg scale response was 9 (very light). A slight increase in the respiratory rate was observed while exercising, but no abnormal breathing patterns were observed. The average metabolic equivalents (METs) of the exercise ranged from 1.34 to 1.87, and the average RQ ranged from 0.82 to 0.90. The circulatory-respiratory dynamics observed in this study verified that elderly females with an average age of 70 years could safely perform the Tai Chi Yuttari-exercise. This study helped obtain basic data for expanding the indications for this exercise.
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