Gotshall R W, Bauer T A, Fahrner S L
Department of Exercise and Sport Science, Colorado State University, Fort Collins 80523, USA.
Int J Sports Med. 1996 Jan;17(1):17-21. doi: 10.1055/s-2007-972802.
Previous studies on cycling cadence have focused on the economy of the cadence, in search of the optimal pedal cadence. The purpose of this study was to determine the hemodynamic changes associated with varying pedal cadence at a constant workload. It was hypothesized that increased pedal cadence would enhance the skeletal muscle pump, resulting in elevation of cardiac output. Seven cyclists were enlisted to cycle at 200 watts at pedal cadences of 70, 90 and 110 rpm (random order). Oxygen uptake, heart rate, stroke volume, cardiac output, blood pressure, and vascular resistance were determined. As has been previously shown, oxygen uptake increased with increased cadence (70, 90, 110 rpm) at this workload. Heart rate, stroke volume, cardiac output and blood pressure were increased, and vascular resistance decreased, with increased cadence. Cardiac output increased (34%) in excess of the increase in oxygen uptake (15%) as shown by the decrease (-14.5%) in the arterial-venous oxygen difference occurring with increasing cadence. Apparently, even though the workload was constant, the increase in pedal cadence resulted in a more effective skeletal-muscle pump which increased muscle blood flow and venous return. It is not known if this might contribute to the natural selection of higher cadences by cycling athletes, even though there is reduced economy.
先前关于骑行踏频的研究主要集中在踏频的经济性上，以寻找最佳的踏板踏频。本研究的目的是确定在恒定工作量下，与不同踏板踏频相关的血液动力学变化。研究假设是，增加踏板踏频会增强骨骼肌泵功能，从而导致心输出量增加。招募了7名自行车运动员，让他们在踏板踏频为70、90和110转/分钟（随机顺序）的情况下以200瓦的功率骑行。测定了摄氧量、心率、每搏输出量、心输出量、血压和血管阻力。如先前所示，在该工作量下，摄氧量随踏频增加（70、90、110转/分钟）而增加。随着踏频增加，心率、每搏输出量、心输出量和血压升高，血管阻力降低。随着踏频增加，动脉-静脉氧差下降（-14.5%），表明心输出量增加（34%）超过摄氧量增加（15%）。显然，即使工作量恒定，踏板踏频的增加也会导致更有效的骨骼肌泵功能，从而增加肌肉血流量和静脉回流。目前尚不清楚这是否可能有助于自行车运动员自然选择更高的踏频，尽管经济性有所降低。
