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Updated: Oct 26, 2025

In Vivo Electrophysiological Measurement of the Rat Ulnar Nerve with Axonal Excitability Testing
Published on: February 6, 2018
Eccentric exercise causes delayed sensory nerve conduction velocity but no repeated bout effect in the flexor
Eisuke Ochi1,2, Hisashi Ueda3, Yosuke Tsuchiya4
1Faculty of Bioscience and Applied Chemistry, Hosei University, 3-7-2, Kajino, Koganei, Tokyo, 184-8584, Japan. ochi@hosei.ac.jp.
Purpose:
This study was aimed at investigating the effect of eccentric contractions (ECCs) of flexor pollicis brevis muscles (FPBMs) on motor and sensory nerve functions as well as the ipsilateral repeated bout effect (IL-RBE) and contralateral (CL)-RBE of motor and sensory nerve conduction velocities following ECCs.
Methods:
Thirty-two young healthy men (age: 19.6 ± 0.2 years, height: 173.2 ± 1.2 cm, body mass: 69.7 ± 1.9 kg) performed two bouts of ECCs. During the first ECCs bout (ECCs-1), all participants performed 100 ECCs with 1 hand; for the second bout, 3 groups (2 weeks [W]: n = 11, 4W: n = 10, 8W: n = 11) performed ECCs with both hands 2, 4, or 8 weeks after ECCs-1. The maximal voluntary isometric contraction (MVC), range of motion (ROM), visual analog scale for pain (VAS), motor and sensory nerve conduction velocities were measured before, immediately after, and 1, 2, 3, and 5 days after ECCs.
Results:
ECCs-1 decreased the MVC, limited the ROM, developed VAS, and decreased the motor and sensory nerve conduction velocities compared to non-exercise hand (p < 0.05). The repeated bout effect was observed in the ROM for IL-RBE in 2W and 4W, VAS for IL-RBE in 2 W, and ROM and VAS for CL-RBE in 2W (p < 0.05). However, RBEs of MVC and motor and sensory nerve conduction velocities were not observed, and no differences were confirmed depending on the interval.
Conclusion:
In the present study, ECCs of the FPBM caused a sensory nerve dysfunction, while IL- or CL-RBE was not observed.
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