本研究目的在探討速度-時間非線性模式(V-T)、速度-時間倒數線性模式 (V-1/T)、距離-時間線性模式(D-T)和三參數非線性模式(3P)所得之臨界速 度(critical velocity；CV)的差異及其與運動表現的相關。受試對象為18名 國內優秀表少年游逑選手，所有受試者皆需接受25m、50m、100m 200m、400m最大努力捷泳測驗，再以此成績利用SAS統計軟體計算各種 數學模式之CV。結果各數學式之 CV，經由變異數分析後，發現除V-T 非線性模式分別與D-T線性模式和3P非線性模式無顯著差異外，其餘各組皆 達顯著差異水準。各數學模式之CV與運動表現的相關，隨著運動距離的增加 而增加(r=0.90∼0.99)。顯示各數學模式之CV皆能代表游泳選手之有氧 運動能力，但是，不同數學模式之CV並不相同，以3P非線性模式之CV最 低，D-T線性模式的計算方法最簡便，兩者相關更高達0.97，因此，可利用 迴歸公式；3P模式CV=.08905×-D-T模式CV+0.2146，增進臨界負荷 的實用性。

　　　　　The pruposes of tnis study are to investigate critical velocity (CV) derived from velocity-time (V-T) nonlingrar model, velocity-1/time(V-1/T)linear model, distancetime (D-T)linear model and 3-parameter (3-P)nonlinear model. Subjects are 18 male juvenile swimmers (mean ± DS； 15.4 ± 1.64yr； 167.9 ± 6.48cm, 58.2 ± 8.20 kg)Each subject swam five different distances (25m. 50m. 100m,200m and 400m) with freestyle at their maximal effort and the time to complete each distance was recorded for assessing critical velocity by various mathematical models. Significant differences were found among CV's deriveed from different mathematical models The data showed high coefficient of correlation (r=0.90 ∼ 0.99) between performance of all distance and CV form varied mathematical models. The longer the swimming distance, the higher coefficient of correlation was also found. Since the simplicity for calculation and high coefficient of correlation with swimming perfomancw (100m：r=0.92, 200m：r=0.97, 400m： r=0.99, it is suggested that D-T linear model is the best choice for CP estimation for juvenile swimmers.