Ratel Sébastien, Duché Pascale, Hautier Christophe A, Williams Craig A, Bedu Mario
Laboratoire Interuniversitaire de Biologie des Activités Physiques et Sportives, UFR de Médecine-Université d'Auvergne, Clermont-Ferrand, France.
Eur J Appl Physiol. 2004 Jan;91(1):100-4. doi: 10.1007/s00421-003-0937-9. Epub 2003 Sep 4.
The aim of the present study was to compare physiological data obtained during cycling using a noncircular "Harmonic" chainring versus a standard circular chainring over a range of speeds and slopes in endurance-trained cyclists. Thirteen male subnational cyclists (16-45 years) performed two maximal graded exercises on their own bicycle: one with a circular chainring, the other with a Harmonic chainring with the same gearwheel (52 teeth). The two chainrings were randomly assigned to avoid learning effects. The tests were carried out on a simulator. Speeds and/or slopes were increased every 2 min 30 s until exhaustion of the subject. Ventilation, oxygen uptake, carbon dioxide output, respiratory exchange ratio, and heart rate were continuously measured during the tests. Blood lactate concentration was measured during the last 30 s of each level. No significant difference was observed in any of the submaximal parameters measured during the tests ( P>0.05). Similarly, maximal values were not statistically different ( P>0.05). In conclusion, although the design of the Harmonic chainring was based on optimization analysis, comparison of the physiological response in this study did not translate into an advantage of the Harmonic over circular chainring during submaximal and maximal pedaling in trained cyclists.
本研究的目的是比较耐力训练的自行车运动员在一系列速度和坡度下使用非圆形“谐波”链轮与标准圆形链轮骑行时获得的生理数据。13名国家二级男子自行车运动员（16 - 45岁）在自己的自行车上进行了两次最大分级运动：一次使用圆形链轮，另一次使用具有相同齿轮（52齿）的谐波链轮。两个链轮随机分配以避免学习效应。测试在模拟器上进行。每2分30秒增加一次速度和/或坡度，直至受试者力竭。测试期间连续测量通气量、摄氧量、二氧化碳排出量、呼吸交换率和心率。在每个水平的最后30秒测量血乳酸浓度。测试期间测量的任何次最大参数均未观察到显著差异（P>0.05）。同样，最大值在统计学上也没有差异（P>0.05）。总之，尽管谐波链轮的设计基于优化分析，但本研究中生理反应的比较并未表明在训练有素的自行车运动员进行次最大和最大蹬踏时，谐波链轮比圆形链轮具有优势。
