緒論:近年來,功能性閾值功率(functional threshold power, FTP)為評估自由車騎乘表現的重要指標,其被認為在長時間騎乘過程中,血乳酸濃度能夠維持在平穩的狀態。由於FTP測試時間較長,已簡化為20分鐘的平均功率,並以FTP_(20)表示;不過FTP_(20)反應出哪些負荷因素,則需要進一步地驗證。因此,本研究目的為探討FTP_(20)與運動表現參數之相關性。方法:25名訓練有素的高中自由車選手,以最大努力表現進行FTP_(20)測試及漸增負荷測試,以平均值與標準差呈現FTP_(20)與攝氧量、乳酸及心率等各項運動表現參數,再以皮爾森相關係數分析FTP_(20)與運動表現參數之間的相關性。結果:FTP_(20)與最大攝氧量、最大有氧功率、峰值功率輸出、乳酸閾值下攝氧量、乳酸閾值下功率、乳酸閾值下心率、個人乳酸閾值下攝氧量、乳酸閾值下功率及平均心率皆達顯著相關(r = -.413~ .877),其中FTP_(20)與最大攝氧量及最大有氧功率的相關性最高(r = .857; r = .877)。結論:本研究發現,最大攝氧量、最大有氧功率、乳酸閾值下攝氧量及乳酸閾值下功率等運動負荷,為影響FTP_(20)能力的關鍵因素,建議基層訓練的教練或運動科學研究員,能夠將訓練目標設定為最大攝氧量以及下肢肌群的肌力與耐力,進而提升臺灣高中選手在長時間騎乘時的踩踏力量及轉速。
Introduction: Functional threshold power (FTP) has recently become a crucial metric for evaluating cycling performance. FTP represents an estimate of the maximal steady state of blood lactate concentrations during long-term cycling, assessed as the average power value in a 20-minute test (FTP_(20)). However, the sports performance parameters reflected by FTP_(20) require further confirmation through laboratory tests. This study aimed to investigate the relationship between FTP_(20) and sports performance parameters. Methods: Twenty-five well-trained high school cyclists performed the FTP_(20) test and graded exercise tests with maximum effort. The FTP_(20) and various sports performance parameters, such as oxygen uptake, lactic acid, and heart rate, are presented as the mean and standard deviation. Pearson's correlation coefficient (r) was used to examine the correlations between FTP_(20) and sports performance parameters. Results: FTP_(20) was significantly correlated with maximum oxygen uptake (V̇O_(2max)), maximum aerobic power (MAP), peak power output, oxygen uptake at onset of blood lactate accumulation (OBLA_(vo2)), power output at onset of blood lactate accumulation (OBLA_(power)), heart rate at onset of blood lactate accumulation (OBLA_(HR)), oxygen uptake at individual lactate threshold (ILT_(vo2)), power output at individual lactate threshold (ILT_(power)), and average heart rate (HR_(avg)) (r = -0.413-0.877). FTP_(20) was most strongly correlated with V̇O_(2max) (r = 0.857) and MAP (r = 0.877). Conclusion: This study found that key factors affecting the FTP_(20) included sports performance parameters such as V̇O_(2max), MAP, OBLA_(vo2), and OBLA_(power). Therefore, V̇O_(2max), muscle strength, and endurance of the lower body muscles should be improved to enhance the pedaling power and speed of high school cyclists in Taiwan during prolonged cycling.