Ingestion of an ample amount of meat substitute based upon a lysine-enriched, plant-based protein blend stimulates postprandial muscle protein synthesis to a similar extent as an isonitrogenous amount of chicken in healthy, young men.

Plant-based proteins are considered to be less effective in their capacity to stimulate muscle protein synthesis when compared with animal-based protein sources, likely due to differences in amino acid contents. We compared the postprandial muscle protein synthetic response following the ingestion of a lysine-enriched plant-based protein product with an isonitrogenous amount of chicken. Twenty-four men (age: 24±5 y; BMI: 22.9±2.6 kg·m-2) participated in this parallel, double-blind, randomised controlled trial and consumed 40 g protein as a lysine-enriched wheat and chickpea protein product (Plant, n=12) or chicken breast fillet (Chicken, n=12). Primed, continuous intravenous L-[ring-13C6]-phenylalanine infusions were applied while repeated blood and muscle samples were collected over a 5h postprandial period to assess plasma amino acid responses, muscle protein synthesis rates, and muscle anabolic signalling responses. Postprandial plasma leucine and essential amino acid concentrations were higher following Chicken (P<0.001), while plasma lysine concentrations were higher throughout in Plant (P<0.001). Total plasma amino acid concentrations did not differ between interventions (P=0.181). Ingestion of both Plant and Chicken increased muscle protein synthesis rates from post-absorptive: 0.031±0.011 and 0.031±0.013 to postprandial: 0.046±0.010 and 0.055±0.015%∙h-1, respectively (P-time<0.001), with no differences between Plant and Chicken (P-interaction=0.068). Ingestion of 40 g protein in the form of a lysine-enriched plant-based protein product increases muscle protein synthesis rates to a similar extent as an isonitrogenous amount of chicken in healthy, young men. Plant-based protein products sold as meat replacers may be as effective as animal-based protein sources to stimulate postprandial muscle protein synthesis rates in healthy, young individuals.