Excessive exercise induces cardiac arrhythmia in a young fibromyalgia mouse model

• Published in: PloS one 2020-09, Vol.15 (9), p.e0239473-e0239473
• Main Authors: Nakata, Taiki, Doi, Atsushi, Uta, Daisuke, Yoshimura, Megumu, Shin, Min-Chul, Ito, Etsuro
• Format: Article
• Language: English
• Subjects: Animal models; Arrhythmia; Arthritis; Biology and Life Sciences; Bone surgery; Cardiac arrhythmia; Cardiac function; Cardiovascular disease; Causes of; Cognition & reasoning; Complications; Complications and side effects; Earth Sciences; EKG; Electrocardiography; Electrodes; Exercise; Experiments; Fibromyalgia; Gait; Health aspects; Heart rate; Laboratory animals; Medicine and Health Sciences; Motor activity; Open source software; Pain; Physical training; Production methods; Rehabilitation; Research and Analysis Methods; Reserpine; Shallow water; Walking; Warm water; Water treatment
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0239473

Background Fibromyalgia patients experience cardiovascular complications in addition to musculoskeletal pain. This study aimed to investigate the cardiac effects of a prolonged shallow water gait in a fibromyalgia-induced young mouse model. Methods To produce a fibromyalgia mouse model, wild-type mice were administered an intraperitoneal injection of reserpine once a day for three days, and two primary experiments were performed. First, three types of gait tests were performed before and after the reserpine injections as follows: (i) 5 minutes of free gait outside the water, (ii) 1 minute of free gait in shallow warm water, and (iii) 5 minutes of free gait in shallow warm water. Second, electrocardiogram recordings were taken before and after the three gait tests. The average heart rate and heart rate irregularity scores were analyzed. Results Exercise-induced cardiac arrhythmia was observed at 1-minute gait in shallow water during the acute stage of induced FM in young mice. Further, both cardiac arrhythmia and a decrease in HR have occurred at 5-minute gait in shallow water at the same mice. However, this phenomenon was not observed in the wild-type mice under any test conditions. Conclusion Although a short-term free gait in shallow warm water may be advantageous for increasing the motor activity of FM-model mice, we should be aware of the risk of prolonged and excessive exercise-induced cardiac arrhythmia. For gait exercises in shallow water as a treatment in FM patients. We suggest a gradual increase in exercise duration may be warranted.