The purpose of this study was to evaluate the cardiorespiratory response and energy expenditure during the practice of Tai-Chi-Qui-Gong (TCQG). Forty-seven TCQG practitioners with a mean age of 60.7 +/- 9.9 years participated in this study. The cardiorespiratory responses and energy expenditure were measured by a K4 telemetry system. TCQG has 54 motions and can be divided into 3 sets. The result indicated that the exercise intensity of each motion is about 3 metabolic equivalents (MET) and the energy expenditure of each set is about 60 Kcal. The estimated intensity of TCQG in elderly individuals approximated 50% of the maximum oxygen uptake (vO2max) for men, and 60% of the maximum oxygen uptake (vO2max) for women. The findings demonstrate that TCQG is a low intensity exercise and can be prescribed as an alternative exercise program for cardiopulmonary rehabilitation.