Institute of Sports Medicine, Department of Orthopedic Surgery M81, Bispebjerg Hospital, Copenhagen NV, Denmark.
Nutrients. 2013 Mar 13;5(3):852-76. doi: 10.3390/nu5030852.
Ingestion of protein is crucial for maintenance of a variety of body functions and within the scope of this review we will specifically focus on the regulation of skeletal muscle mass. A quantitative limitation exists as to how much muscle protein the body can synthesize in response to protein intake. Ingestion of excess protein exerts an unwanted load to the body and therefore, it is important to find the least amount of protein that provides the maximal hypertrophic stimulus. Hence, research has focused on revealing the relationship between protein intake (dose) and its resulting stimulation of muscle protein synthesis (response). In addition to the protein amount, the protein digestibility and, hence, the availability of its constituent amino acids is decisive for the response. In this regard, recent studies have provided in-depth knowledge about the time-course of the muscle protein synthetic response dependent on the characteristics of the protein ingested. The effect of protein intake on muscle protein accretion can further be stimulated by prior exercise training. In the ageing population, physical training may counteract the development of "anabolic resistance" and restore the beneficial effect of protein feeding. Presently, our knowledge is based on measures obtained in standardized experimental settings or during long-term intervention periods. However, to improve coherence between these types of data and to further improve our knowledge of the effects of protein ingestion, other investigative approaches than those presently used are requested.
蛋白质的摄入对于维持身体的各种功能至关重要。在本次综述中，我们将特别关注骨骼肌质量的调节。人体对蛋白质摄入的反应所能合成的肌肉蛋白质数量存在定量限制。摄入过多的蛋白质会给身体带来不必要的负担，因此，找到提供最大肥大刺激的最小蛋白质量非常重要。因此，研究的重点是揭示蛋白质摄入（剂量）与其对肌肉蛋白质合成的刺激作用（反应）之间的关系。除了蛋白质的数量外，蛋白质的消化率以及其组成氨基酸的可用性对于反应也具有决定性作用。在这方面，最近的研究提供了关于依赖于摄入蛋白质的特性的肌肉蛋白质合成反应的时程的深入知识。蛋白质摄入对肌肉蛋白质合成的影响可以通过先前的运动训练进一步刺激。在老年人群中，体育锻炼可以对抗“合成代谢抵抗”的发展，并恢复蛋白质喂养的有益作用。目前，我们的知识是基于在标准化实验环境中或在长期干预期间获得的测量值。然而，为了提高这些类型的数据之间的一致性，并进一步提高我们对蛋白质摄入的影响的认识，需要采用除目前使用的方法之外的其他研究方法。
