本研究之目的是以腳踏車測力器來評估臨界負荷與PWC170之相關情形。受試者為21名學生，平均年齡23.38±2.44歲，平均身高173.00±3.78公分，平均體重69.24±5.64公斤。所有受試者必須分別接受150W、180W、210W最大努力的踩車運動，依負荷與踩車時間倒數的直線迴歸方程式求得臨界負荷；而PWC170則是以150W、180W、210W最大努力踩車的第三分鐘心跳率，依負荷與心跳率直線迴歸方程式求得。結果顯示臨界負荷平均為107.66±13.29W，而PWC170平均為189.11±11.59W；經 t 考驗結果發現兩者有顯著差異（t=-99.02, P<0.05），但是兩者卻有極高相關（r=0.96,P<0.05），由PWC170預測臨界負荷的迴歸方程式為y=1.19x-117.43，預測的變異解釋量達93%。本研究結果顯示臨界負荷與PWC170有極高相關，同時臨界負荷可由PWC170加以預測。

The purpose of this study was to evaluate the relationship between critical power and PWC170 for cycle ergometry. Twenty-one students with mean age, height and body weight of 23.38 (SD=2.44)yrs, 173.00(SD=3.78)cm, and 69.24(SD=5.64)kg, respectivly were studied. All subjects performed 150W, 180W, 210W cycle exercise to exhaustion in random order for critical power and PWC170 with a linear power -1/time model and a linear power-heart rate(the third minute) model. Results for critical power and PWC170 were 107.66±13.29W and 189.11±11.59W respectively. Related t-test and correlation analysis revealed that there were significant differences (t=-99.02, P<0.05), but significant correlation (r=0.96, P<0.05) between PWC170 and critical power. Critical power could be predicted by regression equation: y=1.19x-117.43. It is concluded that PWC170 and critical power were significantly correlated, and critical power could be predicted validly by PWC170.