阻力運動是增加肌力與肌肥大最有效的運動模式,但詳細分子機制仍未完全瞭解。本文旨在探討急性阻力運動引起的荷爾蒙反應與肌細胞內涉及蛋白質合成的分子機制,以及荷爾蒙、胺基酸與肌細胞間的交互作用對運動後肌肉蛋白質合成之影響。經文獻回顧後,本文作出以下總結:一、急性阻力運動對生物體與肌細胞造成極大的生理壓力,並起動一系列複雜的荷爾蒙交互作用與細胞分子訊息系統,造成細胞蛋白質合成與肌肥大現象;二、阻力運動期間,異化性荷爾蒙與分子訊息活性增加並導致肌肉蛋白質合成下降;三、阻力運動停止後,機械性蛋白合成訊息與合成性荷爾蒙分泌增加,進而活化細胞內合成性分子訊息系統並刺激衛星細胞分化協助肌纖維肥大;四、阻力運動後增補蛋白質或胺基酸可使肌肉蛋白質合成現象獲得加成效果。
Resistance exercise is a widely used exercise modality for enhancing muscle strength and hypertrophy. However, the molecular mechanisms mediating acute resistance exercise-induced muscle protein synthesis have not been completely understood. In this article, we reviewed the hormonal responses and intramuscular molecular signaling systems involve in muscle protein turnover during and after acute resistance exercise, as well as the possible molecular mechanisms by which amino acids mediate post-exercise muscle protein synthesis from current literature. Acute resistance exercise is recognized as a strong stress to both human body and muscle cell. In order to cope with this physiological stress, a series of hormonal responses and intramuscular signaling transduction systems, which involve in muscle protein synthesis and growth, are initiated during and after acute resistance exercise. During resistance exercise, the catalytic hormones and intracellular signaling systems override the protein synthetic effect, thereby reducing net protein synthesis in skeletal muscle. In the post-exercise period, the sustained mechanical stress-induced protein synthesis and the releasing of anabolic hormones synergistically activate protein synthesis and muscle hypertrophy in skeletal muscle via activating protein synthetic signaling systems and satellite cell proliferation. Furthermore, after resistance exercise, the ingestion of supplements containing protein or amino acids is capable of obtaining greater muscle protein synthetic effect during postexercise recovery.