Department of Rehabilitation Sciences, Kobe University Graduate School of Health Sciences, Kobe, Japan.
Department of Musculoskeletal Functional Research and Regeneration, Graduate School of Biomedical and Health Sciences, Hiroshima University, Minami-ku, Hiroshima, Japan.
Kobe J Med Sci. 2021 Sep 30;67(2):E48-E54.
An experimental animal model that causes mild structural disorders of skeletal muscles is essential to understand general exercise-induced muscle damage. Thermal stimulations such as icing and heating are commonly used as treatments for muscle injuries in sports. We established a downhill running (DR) protocol that leads to structural muscle disorders without sarcolemmal disruption and directly compared the structural changes produced by icing and heating after DR. Male ddY mice were divided into the DR, DR plus icing (Ice), and DR plus heating (Heat) groups. All mice ran at 20 m/min, -20% grade on a treadmill for a total of 90 min (three rounds of 30 min). In the Ice and Heat groups, an ice pack and a hot pack were, respectively, applied to the exercised triceps brachii muscles for 20 min just after DR. The proportion of myofibers with structural disorders was higher in the Ice group than in the DR and Heat groups at days 1 and 7 after DR. Moreover, the structural disorder of myofibers was slightly improved in the Heat group at day 1 after DR compared with the DR group. These findings suggest that icing treatment might aggravate the structural changes after DR.
建立一种可导致轻微骨骼肌结构紊乱的实验动物模型对于理解一般运动引起的肌肉损伤至关重要。热刺激，如冰敷和热敷，常用于运动中肌肉损伤的治疗。我们建立了一种下坡跑步（DR）方案，该方案可导致结构肌肉紊乱而不会破坏肌膜，并直接比较 DR 后冰敷和热敷引起的结构变化。雄性 ddY 小鼠分为 DR、DR 加冰敷（Ice）和 DR 加加热（Heat）组。所有小鼠均在跑步机上以 20m/min、-20%坡度跑 90 分钟（共 3 轮，每轮 30 分钟）。在 Ice 和 Heat 组中，在 DR 后立即将冰袋和热袋分别应用于运动后的肱三头肌 20 分钟。与 DR 和 Heat 组相比，在 DR 后第 1 和第 7 天，Ice 组中具有结构紊乱的肌纤维比例更高。此外，与 DR 组相比，在 DR 后第 1 天，Heat 组的肌纤维结构紊乱略有改善。这些发现表明，冰敷治疗可能会加重 DR 后的结构变化。
