彎形曲柄對自由車衝刺表現及運動經濟性之影響

Abstract

目的：探討彎形曲柄對於自由車選手衝刺表現及運動經濟性之影響。方法：15名受過訓練的男性自由車選手，先在Cyclus2腳踏車固定式測功儀上進行一次最大攝氧量測試，接著進行兩階段共四次測試，每次測試間隔3天，第一階段中，受試者隨機分配，在兩次測驗中分別使用直形與彎形兩種不同曲柄，以100W的運動強度熱身10分鐘後，隨即進行30秒溫蓋特無氧動力測驗，並全程記錄踩踏功率。第二階段中，受試者隨機分配，在兩次測驗中分別使用直形與彎形兩種不同曲柄，在Cyclus2腳踏車測功儀上以80% VO2max的運動強度踩踏5分鐘後，隨即進行30秒溫蓋特無氧動力測驗，並全程記錄踩踏功率及氣體分析。結果：(1)平均動力輸出、最大動力輸出及疲勞遞減率等衝刺運動表現均未達顯著差異，中高強度後30秒溫蓋特無氧動力測驗平均迴轉速達顯著差異。(2)攝氧量、換氣量、呼吸交換率及心跳率等運動經濟性相關生理數值均未達顯著差異。結論：男性自由車選手使用彎形曲柄能夠些微增加30秒溫蓋特無氧動力測驗的平均動力輸出及最大功率輸出，但未能達到統計上顯著差異，建議未來可以不同實驗設計進行進一步探討。Purpose: To investigate the effect of curve crank on cycling sprint performance and efficiency in male cyclists. Methods: Fifteen male cyslists were recruited and participated in four exercise trials on Cyclus2 stationary ergometer with different cranks. Each exercise trial was performed at least three days apart. In the first stage, following a warming up trial for 10 minutes at 100W, the subjects performed 30s Wingate Anaerobic Power Test to measure cycling performance i.e., mean power, peak power, fatigue index and cadence. In the second stage, following a warming up trial for 10 minutes at 100W, the subjects cycled at 80% VO2max for 5 minutes. Then immediately performed 30s Wingate Anaerobic Power Test to measure physiological responses and performance, i.e., oxygen uptake, ventilatory, heart rate, respiratory exchange ratio, mean power, peak power, fatigue index, cadence, RPE. Results: No significant differences were found on the all physiological variables or performance between two groups. Conclusion: Male road cyclists may not improve sprint performance or efficiency in cycling with curve crank. Further testing will be helpful to define the possible improvements of curve crank.