Murphy Caoileann H, Hector Amy J, Phillips Stuart M
a Department of Kinesiology , McMaster University , Hamilton , ON , Canada.
Eur J Sport Sci. 2015;15(1):21-8. doi: 10.1080/17461391.2014.936325. Epub 2014 Jul 11.
A large body of evidence now shows that higher protein intakes (2-3 times the protein Recommended Dietary Allowance (RDA) of 0.8 g/kg/d) during periods of energy restriction can enhance fat-free mass (FFM) preservation, particularly when combined with exercise. The mechanisms underpinning the FFM-sparing effect of higher protein diets remain to be fully elucidated but may relate to the maintenance of the anabolic sensitivity of skeletal muscle to protein ingestion. From a practical point of view, athletes aiming to reduce fat mass and preserve FFM should be advised to consume protein intakes in the range of ∼1.8-2.7 g kg(-1) d(-1) (or ∼2.3-3.1 g kg(-1) FFM) in combination with a moderate energy deficit (-500 kcal) and the performance of some form of resistance exercise. The target level of protein intake within this recommended range requires consideration of a number of case-specific factors including the athlete's body composition, habitual protein intake and broader nutrition goals. Athletes should focus on consuming high-quality protein sources, aiming to consume protein feedings evenly spaced throughout the day. Post-exercise consumption of 0.25-0.3 g protein meal(-1) from protein sources with high leucine content and rapid digestion kinetics (i.e. whey protein) is recommended to optimise exercise-induced muscle protein synthesis. When protein is consumed as part of a mixed macronutrient meal and/or before bed slightly higher protein doses may be optimal.
大量证据表明，在能量限制期间摄入较高蛋白质（2 - 3倍于蛋白质推荐膳食摄入量（RDA），即0.8克/千克/天）可以增强去脂体重（FFM）的保持，尤其是与运动相结合时。高蛋白饮食对FFM的保护作用背后的机制仍有待充分阐明，但可能与维持骨骼肌对蛋白质摄入的合成代谢敏感性有关。从实际角度来看，建议旨在减少脂肪量并保持FFM的运动员摄入约1.8 - 2.7克/千克/天（或约2.3 - 3.1克/千克FFM）的蛋白质，同时保持适度的能量赤字（-500千卡）并进行某种形式的抗阻运动。在这个推荐范围内的蛋白质摄入目标水平需要考虑许多具体情况因素，包括运动员的身体成分、习惯性蛋白质摄入量和更广泛的营养目标。运动员应专注于摄入优质蛋白质来源，目标是在一天中均匀分布蛋白质摄入。建议在运动后从亮氨酸含量高且消化动力学快的蛋白质来源（即乳清蛋白）中摄入0.25 - 0.3克/餐的蛋白质，以优化运动诱导的肌肉蛋白质合成。当蛋白质作为混合宏量营养素餐的一部分食用和/或在睡前食用时，稍高的蛋白质剂量可能是最佳的。
