本研究的目的，在透過三參數的非線性臨界速度(critical Velocity , CV)數學模式，進行走路運動CV強度的判定，並且進一步評量CV強度走路運動時的各項生理反應的變化情形，包括心跳率、攝氧量、二氧化碳產生量、換氣量以及自覺量表等人體生理反應，以便能夠確認走路CV的有效性。本研究以經常參與運動的男性大學生20名為受試對象，年齡21.55±1.67 歲、身高170.7±3.93公分、體重61.80±9.57公斤。所有受試者依平衡次序的方式，接受四次實驗室跑步機上的最大持續走路時間測驗(2.0-3.2m/sec)，以確定受試者的走路CV強度。然後，受試者於實驗室內接受走路CV強度的20分鐘運動測驗。研究結果發現，走路CV強度下的運動過程中，攝氧量並不會隨著運動時間的增加而提高；但是，心跳率、換氣量、二氧化碳產生量與自覺量表等人體生理反應，則出現無法達成穩定狀態的情形。本研究以攝氧量證實走路CV的效度，進而確認CV對於評量走路有氧能力的代表性，值得一般運動參與者適度運動的參考與應用。

The purpose of this study was to examine the validity of critical velocity (CV) derived from walking using a 3-parameter critical power model. The walking CV was evaluated according to the variations of physiological data, which include heart rate (HR), oxygen intake (VO2), carbon dioxide output (VCO2), ventilation (VE), and RPE. Twenty male college students (21.55±1.67yrs, 170.70±3.93cm, 61.80±9.57kg) who exercise regularly served as subjects in this study. At the first session, each subject performed four constant velocity exhaustive treadmill tests (2.0-3 .2m/sec) to determine walking CV in a counter balance order. Then, participants performed a .20-minute continuous treadmill test at their walking CV. In the second session, the response of oxygen intake maintained a constant while examining the validity of walking CV, but the other physiological responses increased with time. The result proved that the 3-parameter critical power model was valid to predict walking CV by VO2. At the same time, it brought the representative of examining walking aerobic ability, which was useful for participants of moderate exercise.