In men undergoing a 12-week resistance training program, supplementation with plant-based protein and animal-based protein results in similar increases in muscle mass and strength.

Study: A Novel Plant-Based Protein Has Similar Effects Compared to Whey Protein on Body Composition, Strength, Power, and Aerobic Performance in Professional and Semi-Professional Futsal Players

Men who took either plant-based or whey protein while lifting weights gained the same amount of muscle and strength — the study found no difference between the two types of protein.

Study: Efficacy of Pea Protein Supplementation in Combination with a Resistance Training Program on Muscle Performance in a Sedentary Adult Population: A Randomized, Comparator-Controlled, Parallel Clinical Trial

Men who took pea protein (from plants) while lifting weights gained just as much muscle and strength as those who took whey protein (from milk). The study found no real difference between the two.

Study: Similar effects between animal-based and plant-based protein blend as complementary dietary protein on muscle adaptations to resistance training: findings from a randomized clinical trial

Men who lifted weights for 12 weeks and took either plant-based or whey protein supplements gained the same amount of muscle and strength — the study found no difference between the two types of protein.

Study: Long-term effects of plant vs. animal protein supplementation on body composition, muscle strength, physical performance, and cardiometabolic risk factors in adults:a systematic review and meta-analysis of randomized controlled trials

This study found that whether men took protein from plants or animals while lifting weights, they gained about the same amount of muscle and strength over time — so the type of protein doesn’t seem to matter as long as they get enough.