Updated: Sep 25, 2018
As both an animal lover and casual bodybuilder, I have found it difficult to reconcile the need for high protein intake during training with my ethical beliefs that support the vegan or plant-based diet and lifestyle. This concern has been my biggest obstacle to going vegan, or even vegetarian! While I have come across plenty of stories and research of successful vegan endurance athletes, I wonder… how feasible is it to be a successful bodybuilder eating a plant-based diet?
Nutritional Phases of Bodybuilding
In the bodybuilding world, there are two commonly referenced phases of competition preparation in relation to dietary choices: bulking, and cutting. While there is a third phase known as maintenance, the results of the bulking and cutting phases tend to be the most sought after and focused on.
During the bulking phase, the goal is to increase muscle size, a process also known as muscle protein synthesis. Once this has been achieved, body composition improvements (primarily in the form of fat loss) occur during the cutting phase .
Nutritionally speaking, macronutrient composition changes between these two phases. The bulking phase is characterized by a high carbohydrate, moderate protein diet, with moderate fat intake and a caloric excess, whereas a low carbohydrate, high protein diet, with moderate fat intake and a caloric deficit is followed during a cutting phase.
The International Society of Sports Nutrition states that consuming 1.4 to 2.0 grams of protein per kilogram of body weight per day is sufficient for building muscle, but there is some evidence that a high protein intake of 3 or more grams per kilogram per day could improve body composition in individuals that are resistance-trained . In other words, individuals interested in reducing their body fat percentage and/or are in the cutting phase of their program could benefit from eating higher amounts of protein than they do during their muscle building (bulking) phase. Furthermore, it is recommended for athletes to divide their protein consumption into 4-6 servings of 20-40 grams. Bodybuilders specifically tend to follow the guideline of 1.6 to 2.2 g/kg/day (or about 1 g per pound of body weight per day) for bulking, and 1 to 3 grams per kg per day for cutting . To give you some perspective, this means that according to these recommendations, a 120 pound female would need to consume about 76-120 grams of protein each day during her bulking phase, and anywhere between 120 and 163 grams during her cutting phase. That would be 6 servings of 20 grams of protein every day.
Here are some plant-based equivalencies:
1 cup tofu
1 ounce seitan
1 Beyond burger
3 ounces Hempeh
100 grams tempeh
100 grams black beans
Each of these choices contain about 20 grams of protein. Not to mention many of your vegetables and fats will contribute to your protein intake as well.
Okay, so it can be done! But let’s take a look at the comparison of animal and plant protein…
Animal vs. Plant Protein Sources
While animal proteins are complete proteins – meaning they contain all 9 of the essential amino acids – it is specifically the branched-chain amino acids, and leucine in particular, that stimulate muscle protein synthesis, a marker of the bulking phase.
Compared to whey protein isolate, which is a common supplement used by those in the bodybuilding community, there is a lower leucine content in plant-based proteins [3,4]. Per 100 grams of pea protein, there are 6.4 grams of leucine, compared to 8.6 grams in 100 grams of whey protein . In rice protein, there is about 8% leucine, whereas whey is 11.5% . There is also a lower total amino acid appearance in the blood following rice protein ingestion compared to whey protein ingestion. However, a study has found that adding a plant-protein specific digestive enzyme blend to the plant protein, there was no longer any significant difference between the amount of amino acid appearance in blood following rice or whey protein consumption .
With regards to training results, significant performance differences have not been demonstrated between athletes supplementing with plant-based protein and those supplementing with whey protein. Muscle thickness, muscular strength, lean body mass, and perceptions of recovery are similar in both groups of athletes when they have been following identical resistance training programs [3,4]. Not to mention, that with plants you also receive healing phytonutrients, powerful antioxidants and gut-loving fiber.
Bodies Built By Plants
Considering the current research, plant-fueled athletes can achieve the same success in the bodybuilding world as a meat-eater. I want to know, would you make the switch… or are you stuck in your “wheys?”
MacCormick T. The Complete Guide to Bulking and Cutting: Diet Periodization for Bodybuilders. T NATION. https://www.t-nation.com/diet-fat-loss/the-complete-guide-to-bulking-and-cutting. Published 2017.
Jager R, Kerksick CM, Campbell BI, et al. International Society of Sports Nutrition Position Stand: protein and exercise. J Int Soc Sports Nutr. 2017;14:20.
Babault N, Paizis C, Deley G, et al. Pea proteins oral supplementation promotes muscle thickness gains during resistance training: a double-blind, randomized, Placebo-controlled clinical trial vs. Whey protein. J Int Soc Sports Nutr. 2015;12(1):3.
Joy JM, Lowery RP, Wilson JM, et al. The effects of 8 weeks of whey or rice protein supplementation on body composition and exercise performance. Nutr J. 2013;12:86.
Minevich J, Olson MA, Mannion JP, et al. Digestive enzymes reduce quality differences between plant and animal proteins: a double-blind crossover study. Journal of the International Society of Sports Nutrition. 2015;12(Suppl 1):P26. doi:10.1186/1550-2783-12-S1-P26.
Chelsi Brown is a graduate student of the Coordinated Program in Dietetics at Georgia State University. With a background in exercise science and health coaching, she aspires to one day be a sports dietitian, helping athletes to perform and feel their best! In her free time, you can find her at the local gym, playing with her pup Buffy, or dancing her heart out at music festivals.