Dietary protein consumption maximizes the anabolic response during resistance training (RT) by triggering muscle protein synthesis and providing the indispensable amino acids for a net positive protein balance. Leucine is considered the key amino acid in this process, suggesting that differences in protein quality may influence RT-induced gains in muscle mass and strength. In general, plant-based protein sources have lower leucine concentrations than animal-based protein sources and human skeletal muscle. In this respect, despite acute evidence on lower anabolic properties of plant- vs. animal-based protein, the effects of an exclusive plant-based dietary protein diet on RT-induced adaptations are currently unknown.

Inclusion Criteria:

• Healthy young men
• Vegans ≥ 1 y or omnivorous subjects
• Physically active but no resistance-trained subjects
• Without any chronic injury that impairs resistance training performance
• Protein intake > 0.8 g/protein/kg body weight

Exclusion Criteria:

• Use of creatine or beta-alanine supplements for the last 3 months
• Use of proteins and/or amino acids supplements for the last 1 month
• Engagement in specific dietary restrictions
• Previous use of anabolic steroids
• Engagement in any training program