Dietary Protein Distribution Positively Influences 24-h Muscle Protein Synthesis in Healthy Adults

作者：Mamerow, Madonna M.; Mettler, Joni A.; English, Kirk L.; Casperson, Shanon L.; Arentson-Lantz, Emily; Sheffield-Moore, Melinda; Layman, Donald K.; Paddon-Jones, Douglas^*

来源：Journal of Nutrition, 2014, 144(6): 876-880.

DOI：10.3945/jn.113.185280

• OLDER-ADULTS
• ANABOLIC RESPONSE
• BODY-COMPOSITION
• WEIGHT-LOSS
• LEAN MASS
• SARCOPENIA
• RECOMMENDATIONS
• RESISTANCE
• ALLOWANCE
• EXERCISE

The RDA for protein describes the quantity that should be consumed daily to meet population needs and to prevent deficiency. Protein consumption in many countries exceeds the RDA; however, intake is often skewed toward the evening meal, whereas breakfast is typically carbohydrate rich and low in protein. We examined the effects of protein distribution on 24-h skeletal muscle protein synthesis in healthy adult men and women (n = 8; age: 36.9 +/- 3.1 y; BMI: 25.7 +/- 0.8 kg/m(2)). By using a 7-d crossover feeding design with a 30-d washout period, we measured changes in muscle protein synthesis in response to isoenergetic and isonitrogenous diets with protein at breakfast, lunch, and dinner distributed evenly (EVEN; 31.5 +/- 1.3, 29.9 +/- 1.6, and 32.7 +/- 1.6 g protein, respectively) or skewed (SKEW; 10.7 +/- 0.8, 16.0 +/- 0.5, and 63.4 +/- 3.7 g protein, respectively). Over 24-h periods on days 1 and 7, venous blood samples and vastus lateralis muscle biopsy samples were obtained during primed (2.0 mu mol/kg) constant infusion [0.06 mu mol/(kg.min)] of L-[ring-C-13(6)] phenylalanine. The 24-h mixed muscle protein fractional synthesis rate was 25% higher in the EVEN (0.075 +/- 0.006%/h) vs. the SKEW (0.056 +/- 0.006%/h) protein distribution groups (P = 0.003). This pattern was maintained after 7 d of habituation to each diet (EVEN vs. SKEW: 0.077 +/- 0.006 vs. 0.056 +/- 0.006%/h; P = 0.001). The consumption of a moderate amount of protein at each meal stimulated 24-h muscle protein synthesis more effectively than skewing protein intake toward the evening meal.

• 出版日期2014-6