Plant-Powered Muscle: Trials Show Vegans Build Strength as Well as Meat Eaters

Picture the old wrestling grounds of northern India, the akharas, where pehlwani wrestlers trained for hours each day in pits of soft earth. Their diet was famous. It included soaked almonds, chickpeas, lentils, and plenty of milk and ghee. Much of their strength came from humble plant foods. Around the world, from Mexican beans and corn to Japanese tofu and miso, traditional cultures fed hard-working bodies with plant protein for centuries.

Yet a stubborn belief lingers in the gym: if you want to build real muscle, you need meat, eggs, and whey. Plant proteins, the thinking goes, are “incomplete” and too low in the amino acid leucine to switch on muscle growth. In the last few years, well-controlled trials have put that idea to the test. Their answer is good news for anyone who wants to eat more plants and still get stronger.

Key Takeaways

• In a 12-week University of São Paulo trial, vegans and omnivores eating the same amount of protein gained the same muscle mass and strength from resistance training.
• A University of Exeter trial found that a vegan diet built around mycoprotein produced the same thigh muscle growth (about 8%) as a high-protein omnivorous diet over 10 weeks.
• A meta-analysis of 9 trials found soy protein supported strength and lean mass gains equal to whey and other animal proteins.
• Total protein matters more than the source. A major analysis of 49 trials found gains level off at about 1.6 grams of protein per kilogram of body weight per day.
• Combining legumes, grains, soy, nuts, and seeds across the day gives you all the essential amino acids you need.

Why People Doubted Plant Protein

Muscle is built from amino acids. Of the 20 amino acids, nine are “essential,” meaning your body can’t make them and you must get them from food. Leucine is especially important because it acts like an on switch for muscle protein synthesis, the process that repairs and grows muscle after a workout.

Animal proteins tend to be a bit higher in leucine and are digested slightly more efficiently. Many plant foods are lower in one or more essential amino acids. Grains are low in lysine, for example, while beans are lower in methionine. Plant foods also contain less protein per bite, because they come packaged with fiber and starch. On paper, that seems like a handicap.

But traditional cuisines solved the problem long ago by pairing foods. Rice and beans, dal and chapati, hummus and pita, tofu and rice: each combination fills the other’s gaps. The real question is whether these paper differences matter when people actually train and eat.

What the Research Shows

Vegans vs. Omnivores, Head to Head

In 2021, a team led by Victoria Hevia-Larraín and Hamilton Roschel at the University of São Paulo, with muscle scientist Stuart Phillips of McMaster University, published a carefully designed trial in Sports Medicine. They recruited 38 healthy young adults. Half had been vegan for years, and half were habitual meat eaters. Both groups followed the same 12-week resistance training program and ate the same amount of protein, 1.6 grams per kilogram of body weight per day. To hit that target, the vegans used soy protein and the omnivores used whey.

At the end, the two groups had gained the same amount of muscle mass and strength. There was no meaningful difference between them. When protein intake is high enough, the plant-based diet kept up with the meat-based one.

A Fungus-Based Vegan Diet

In 2023, researchers at the University of Exeter, with first author A. J. Monteyne, reported in the Journal of Nutrition on a 10-week trial with 22 young adults doing high-volume resistance training. One group ate a high-protein omnivorous diet. The other ate a vegan diet built largely on mycoprotein, a protein made from fungus. Both groups gained lean mass (about 2.6 kg for omnivores and 3.1 kg for vegans), and thigh muscle grew by roughly 8% in both. Strength gains were also similar.

Soy Matches Whey

Soybeans have been a staple in East Asian diets for thousands of years, and they’re one of the few plant foods that contain all nine essential amino acids in good amounts. In 2018, Mark Messina and colleagues pooled nine trials with 266 participants in the International Journal of Sport Nutrition and Exercise Metabolism. People who added soy protein to resistance training gained strength in the bench press and squat, and they gained lean mass, just as much as those who used whey or other animal proteins.

How Much Protein Is Enough?

A landmark 2018 analysis in the British Journal of Sports Medicine, led by Robert Morton at McMaster University, combined 49 trials with 1,863 people who lifted weights. Adding protein improved gains in muscle and strength, but the benefit leveled off at around 1.6 grams per kilogram of body weight per day. The source of the protein, and whether it was eaten right after a workout or in regular meals, made no difference to the results. For a 175-pound (80 kg) person, that’s about 128 grams of protein a day.

The Bonus Benefits of Building Muscle With Plants

Plant proteins bring more than amino acids. Beans, lentils, and whole grains carry fiber that feeds healthy gut bacteria, plus potassium, magnesium, and antioxidants that support recovery and heart health. As we covered in our look at beans, lentils, and chickpeas, legumes are a staple food in many of the world’s longest-lived communities. Building muscle and caring for your long-term health can go hand in hand.

How to Build a Plant-Powered Muscle Plan

1. Set your protein target. Aim for about 1.6 grams per kilogram of body weight per day. To find your number, divide your weight in pounds by 2.2, then multiply by 1.6. Plant eaters may want to aim a little higher to allow for slightly lower digestibility.
2. Spread protein across the day. Plan three or four meals that each contain a solid serving of protein, rather than loading it all into dinner.
3. Build meals around protein-rich plants. Rely on tofu, tempeh, edamame, lentils, chickpeas, black beans, seitan, and pea or soy protein. A cup of cooked lentils gives you about 18 grams of protein.
4. Pair foods the traditional way. Combine legumes with grains (rice and beans, dal with roti, hummus with whole-grain pita) to round out the essential amino acids, including leucine.
5. Use a plant protein powder if needed. Soy or a pea-and-rice blend makes it much easier to hit higher targets, just as soy powder did in the São Paulo trial.
6. Add nuts and seeds. Pumpkin seeds, hemp seeds, almonds, and peanut butter add protein, healthy fats, and calories for growth.
7. Train progressively. Gradually add weight, reps, or sets over time. Even 30 to 60 minutes of strength training per week brings real health benefits.
8. Support recovery naturally. Sleep 7 to 9 hours, consider creatine (it’s synthetic and vegan-friendly, and vegans often have lower muscle stores to begin with), and explore traditional helpers such as ashwagandha and tart cherry juice.

The Bottom Line

The idea that you need meat to build muscle doesn’t hold up in controlled trials. When protein intake is high enough, vegan and plant-forward diets build muscle and strength just as well as diets based on animal protein. The secret is the same one traditional kitchens have relied on for centuries: eat enough protein, combine your foods well, and train hard and consistently. Your muscles, your gut, and your heart will all benefit.

Frequently Asked Questions

Do I need to combine proteins at every meal?

No. Your body pools amino acids from everything you eat during the day. Eating a variety of legumes, grains, soy, nuts, and seeds across your meals is enough.

Is soy safe for men who want to build muscle?

Yes. Trials of soy protein in men lifting weights showed strength and muscle gains equal to whey. Soy has been a staple food for generations in East Asia.

Do older adults respond the same way?

The trials above mostly studied young adults. Older muscles respond less strongly to protein, so people over 60 may benefit from aiming for the higher end of protein targets and making sure every meal includes a good serving.

What about the gas and bloating from beans?

Increase legumes gradually, soak and rinse dried beans, and cook them with traditional digestive spices such as cumin, ginger, or asafoetida (hing), as Indian cooks have long done.

A note on safety: High-protein diets are safe for healthy people, but if you have kidney disease, talk with your practitioner about the right protein target for you before raising your intake.

Sources

• Hevia-Larraín V, Gualano B, Longobardi I, et al. High-protein plant-based diet versus a protein-matched omnivorous diet to support resistance training adaptations: a comparison between habitual vegans and omnivores. Sports Medicine. 2021. https://doi.org/10.1007/s40279-021-01434-9
• Agência FAPESP. Vegan and omnivorous diets promote equivalent muscle mass gain, study shows. 2021. Agência FAPESP
• Monteyne AJ, et al. Vegan and omnivorous high-protein diets and resistance training adaptations in young adults. Journal of Nutrition. 2023. AZoLifeSciences summary
• Messina M, Lynch H, Dickinson JM, Reed KE. No difference between the effects of supplementing with soy protein versus animal protein on gains in muscle mass and strength in response to resistance exercise. International Journal of Sport Nutrition and Exercise Metabolism. 2018;28(6):674-685. https://doi.org/10.1123/ijsnem.2018-0071
• Morton RW, Murphy KT, McKellar SR, et al. A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. British Journal of Sports Medicine. 2018. McMaster University News

This article is for educational purposes and is not a substitute for personalized advice from a qualified health practitioner.