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Updated: Apr 19, 2026

Assessment of Neuromuscular Function Using Percutaneous Electrical Nerve Stimulation
Published on: September 13, 2015
Heterogeneous neuromuscular activation within human rectus femoris muscle during pedaling
Kohei Watanabe1, Motoki Kouzaki2, Toshio Moritani3
1Laboratory of Neuromuscular Biomechanics, School of International Liberal Studies, Chukyo University, Yagotohonmachi, Showa-ku, Nagoya, 466-8666, Japan.
Introduction:
We investigated the effect of workload and the use of pedal straps on the spatial distribution of neuromuscular activation within the rectus femoris (RF) muscle during pedaling movements.
Methods:
Eleven healthy men performed submaximal pedaling exercises on an electrically braked ergometer at different workloads and with or without pedal straps. During these tasks, surface electromyograms (SEMGs) were recorded from the RF using 36 electrode pairs, and central locus activation (CLA) was calculated along the longitudinal line of the muscle.
Results:
CLA moved markedly, indicating changes in spatial distribution of SEMG within the muscle, during a crank cycle under all conditions (P < 0.05). There were significant differences in CLA among different workloads and between those with and without pedal straps (P < 0.05).
Conclusion:
These results suggest that neuromuscular activation within the RF is regulated regionally by changes in workload and the use of pedal straps during pedaling.
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