In contrast to other rhythmic tasks such as running, the preferred movement rate in cycling does not minimize energy consumption. It is possible that neurophysiological mechanisms contribute to the choice of cadence, however this phenomenon is not well understood. Eleven participants cycled at a fixed workload of 125 W and different cadences including a freely chosen cadence (FCC, ∼72), and fixed cadences of 70, 80, 90 and 100 revolutions per minute (rpm) during which transcranial magnetic stimulation (TMS) was used to measure short interval intracortical inhibition (SICI) and intracortical facilitation (ICF). There was a significant increase in SICI at 70 (P = 0.004), 80 (P = 0.008) and 100 rpm (P = 0.041) compared to FCC. ICF was significantly reduced at 70 rpm compared to FCC (P = 0.04). Inhibition-excitation ratio (SICI divided by ICF) declined (P = 0.014) with an increase in cadence. The results demonstrate that SICI is attenuated during FCC compared to fixed cadences. The outcomes suggest that the attenuation of intracortical inhibition and augmentation of ICF may be a contributing factor for FCC.

与其他有节奏的任务（例如跑步）相比，骑自行车时的首选运动速率不会使能量消耗最小化。神经生理机制可能有助于节奏的选择，但是这种现象尚未得到很好的理解。11名参与者以125 W的固定工作负荷和不同的节奏骑自行车，包括自由选择的节奏（FCC，〜72），以及固定的节奏，每分钟70、80、90和100转（rpm），在此期间经颅磁刺激（TMS）用于测量短时皮质内抑制（SICI）和皮质内促进（ICF）。SICI在70（P  = 0.004），80（P  = 0.008）和100 rpm（P = 0.041）。与FCC相比，ICF在70 rpm下显着降低（P  = 0.04）。抑制-兴奋比（SICI除以ICF） 随着节奏的增加而下降（P = 0.014）。结果表明，与固定节奏相比，SICI在FCC期间衰减。结果提示皮质内抑制的减弱和ICF的增强可能是FCC的促成因素。