Background: Electroacupuncture stimulation is sometimes used to prevent and treat delayed onset muscle soreness (DOMS) induced by exercise; however, the effect is unclear. Using a human biceps brachii muscle pain induction model, we investigated the effect of contralateral electroacupuncture (CEA) versus ipsilateral electroacupuncture (IEA) stimulation on DOMS and muscle injury markers. Methods: Nineteen young men were randomly assigned to receive either CEA or IEA. All participants performed eccentric exercise using the biceps brachii muscle of the nondominant arm to induce muscle damage. Electroacupuncture stimulation (1.5 Hz, 15 minutes) was applied to the dominant arm in the CEA group and the nondominant arm in the IEA group. Electroacupuncture stimulation was applied in both groups from 7 days before exercise to 4 days after exercise. All variables were analyzed at the following seven timepoints: baseline, immediately before exercise, immediately after exercise, and on days 1–4 after exercise. Results: Palpation pain was significantly lower in the IEA group than the CEA group at 72 and 96 hours after exercise. The decrease in the elbow range of motion after exercise was significantly suppressed by electroacupuncture stimulation. The muscle injury markers (creatine kinase, lactate dehydrogenase) increased following exercise, but these changes were not significantly influenced by IEA stimulation. IEA suppressed exercise-induced oxidative stress at 72 hours after exercise. Conclusion: This study suggests that the application of IEA before and after eccentric exercise effectively reduces DOMS. Electroacupuncture might suppress increases in oxidative stress elicited by eccentric exercise.

The authors have declared no competing interest.

UMIN000054171

This study was supported by the JSPS KAKENHI (Grant Number: 22H03485) and Grant in Research Aid for Anna-Massage-Acupressure, Acupuncture and Moxibustion from the Public Interest Incorporated Foundation for Training and Examination in Anna-Massage-Acupressure, Acupuncture and Moxibustion.

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Ethics Statement The study protocol was approved by the ethics committees of the University of Tsukuba, Japan (approval number: Tai019-75) and Teikyo Heisei University (approval number: 2020-100) and followed the ethics principles of the 7th revision (2013) of the Declaration of Helsinki. Participants provided written informed consent and authorization for the disclosure of protected health information before enrolling in the study.

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