The Muscle Protein Synthetic Response to the Ingestion of a Plant-Based Protein Blend Is Not Different From Milk Protein in Healthy, Young Males

Abstract

Abstract Objectives It has been reported that plant-based proteins are not as effective as animal-based proteins in their capacity to stimulate muscle protein synthesis rates. This has been attributed to the lower essential amino acid content and the selective deficiency in specific amino acids. It has been hypothesized that a blend of different plant-based proteins may complement each other and, as such, compensate for such deficits. This study compares post-prandial muscle protein synthesis rates following the ingestion of 30 g milk protein with the ingestion of a 30 g blend of wheat, corn, and pea protein in vivo, in healthy young males. Methods In a randomized, double blind, parallel-group design, 24 healthy young males (24 ± 4 y) received a primed continuous infusion of L-[ring-13C6]-phenylalanine and ingested 30 g milk protein (MILK), or a 30 g protein blend with 15 g wheat, 7.5 g corn, and 7.5 g pea protein (PLANT) in beverage form (n = 12 per group). Both interventional drinks were matched for leucine content. Blood and muscle biopsies were collected for 5 h following protein ingestion to assess post-prandial plasma amino acid profiles and myofibrillar protein synthesis rates. Data are expressed as mean ± SD. Results MILK increased plasma essential amino acid concentrations ∼2 fold more than PLANT over the 5 h post-prandial period (incremental area under curve (iAUC): 151 ± 31 vs 79 ± 12 mmol∙5 h∙L−1 respectively; P < 0.001). Similarly, the leucine iAUC was ∼16% greater for MILK vs PLANT (36 ± 7 vs 31 ± 4 mmol∙5 h∙L−1 respectively; P < 0.05). Ingestion of both MILK and PLANT increased myofibrillar protein synthesis rates when compared to basal post-absorptive values (P < 0.001), with no significant differences between treatments (0.053 ± 0.013 vs 0.064 ± 0.016%∙h−1, respectively; P > 0.05). Conclusions Ingestion of 30 g of a wheat, corn, and pea protein blend increases muscle protein synthesis rates in healthy, young males. The post-prandial muscle protein synthetic response to the ingestion of 30 g of a wheat, corn and pea protein blend does not differ from the ingestion of an equivalent amount of milk protein in healthy, young males. Funding Sources TiFN