The Study for the Reliability and Validity of Incremental Shuttle Walking Test for COPD Patients in Korea

Patients will be required to walk around a 10-m course marked by cones placed 9 m apart, thus allowing 0.5 m for turning at each end. Walking speed will be regulated by prerecorded signals on a compact disc or MP3 file. Patients will increase walking speed at every minute. patients can stop this study, when they can not maintain their speeds due to dyspnea

Exercise stress test will be performed with cycle. When patients perform this study, they will gradually increase the velocity. Investigators will measure electrocardiography, vital sign, oxygen saturation, oxygen uptake, minute ventilation and fatigue.

When participants perform 6 minutes walking test, patients will walk around the tract during 6 minutes. They can their walking speed according to condition and symptom. Investigators records walking distance, pulse rate, oxygen saturation and Borg scale