By following these guidelines, vegan bodybuilders can optimize their diet and training for muscle gain and fat loss success. At the same time, further research explores the nuances of vegan bodybuilding nutrition.
Vegan Bodybuilders: How to Meet Protein Requirements KEY POINTS
- Many vegan bodybuilders fail to meet the proper protein requirements.
- Male and female bodybuilders who were omnivores and vegan were studied in the offseason and during a bodybuilding competition.
- Vegan Bodybuilders met protein requirements in the offseason but failed to Meet Protein Requirements During the Cutting Phase in which higher protein intake was required.
- Both omnivorous and vegan bodybuilders did not reach the RDAs for calcium with diet in any of the two stages of preparation for competition.
- Both female groups (i.e., vegan and omnivore) failed to meet the requirements for iron.
Vegan Diets and Bodybuilding
People have been more interested in veganism lately and want to find out if it can help enhance athletic capabilities, build muscle mass, and boost protein intake. Interest in veganism is rising as people explore how it might give athletes an edge in muscle growth and performance.
Athletes that are vegan have adopted plant-based diets, which have continued to increase, driven by concerns for the environment, animal welfare, and human health.
Vegan Diets and Physical Performance
When comparing physical performance, studies have found no differences between well-planned plant-based and omnivorous diets (i.e., meat-eating diets). (Craddock et al., 2016; Lynch et al., 2018; D. Rogerson, 2017) However, plant-based diets require careful planning when trying to gain muscle.
Plant-based diets reduce appetite due to their high fiber content and low-calorie density, which can benefit weight loss by reducing calorie intake but may pose challenges when an athlete is trying to gain muscle and be in a caloric surplus. (Craddock et al., 2016) Furthermore, getting adequate protein can be difficult for vegan athletes compared to those that eat meat.
Protein Quality and Quantity in Vegan Diets
Vegan athletes should be mindful of their protein intake, as plant-based proteins are often incomplete and contain fewer essential amino acids (EAAs) than animal-based proteins. (Hertzler et al., 2020) However, combining different plant protein sources can improve the overall quality of protein meals by complementing the amino acid composition.
The digestibility of plant-based proteins is typically lower than that of animal products, which may limit muscle protein synthesis and muscle mass gains. The digestibility of plant-based proteins appears to be significantly lower than that of animal products due to anti-nutritional factors such as phytic acid and trypsin inhibitors, oxalates, phenolic compounds, and tannins, which limit the absorption of nutrients. (David Rogerson, 2017) A systematic review of the evidence found that vegans aim to meet their necessary protein intake by consuming protein-dense plant foods like seeds, nuts, legumes, processed meat analogs, and soya protein foods. (David Rogerson, 2017)
Can Vegans Build Muscle Similarly to Meat-Eating Bodybuilders
The idea that vegans cannot build muscle as efficiently as omnivores is a long-standing myth. A 2018 study comparing the effects of different diets on body composition found that vegans had lower muscle mass index and lean body mass compared to omnivores and vegetarians. (Vanacore et al., 2018) However, if a vegan diet is well planned and meets the same protein intake as meat eaters, they can have similar muscle hypertrophy.
Several studies have compared the muscle-building capabilities of vegan and omnivorous athletes. A 2021 study found no significant difference in resistance training adaptations between vegans and omnivores, as both groups achieved similar muscle growth and strength gains. (Hevia-Larraín et al., 2021) It is important to note that a vegan diet must be well-planned to ensure adequate intake of nutrients critical for muscle building, such as protein, fiber, vitamin B12, omega-3 fatty acids, iron, zinc, iodine, calcium, and vitamins.
Bodybuilding Phases: Bulking and Cutting
Bodybuilders undergo two main phases in their bodybuilding competitive cycle: the muscle-gaining or “bulking” phase and the contest preparation or “cutting” phase. The bulking phase aims to increase muscle mass without adding unnecessary body fat, achieved through resistance training and maintaining a positive energy balance with a protein requirement ranging from 1.6 to 2.2 g/kg (.7-1 gram per pound) of body mass.
The cutting phase involves reducing body fat while maintaining muscle mass gained during the bulking phase, typically following a high protein (2.3–3.1 g/kg or 1.04 – 1.4 grams per pound) of body mass), calorie-restricted diet, aerobic exercise, and isometric “posing practice.”
Comparing Vegan Bodybuilders to Omnivore Bodybuilders
A recent study published in the International Journal of Environmental Research and Public Health compared a vegan bodybuilding diet and an omnivore bodybuilding diet during the offseason and during a bulking phase. The study wanted to compare food diaries and macronutrients between the groups. The study consisted of 18 male and female bodybuilders (8 vegan and 10 omnivores). The study’s results highlighted some potential limitations of a vegan diet.
Both groups behaved similarly regarding increasing calories in the offseason and decreasing calories while cutting. Omnivores decreased their calories by an average of 8.5 kcals/kg/day per day while cutting (700 kcals for men and 510 kcals for women). Vegans cut calories by 7.9 kcals per day (665 kcals for men and 385 kcals for women).
Vegan Bodybuilders Failed to Meet Protein Requirements During the Cutting Phase
During bulking, vegan and omnivore bodybuilders met or exceeded the recommended protein range of 1.6–2.2 g/kg/day. Omnivores consumed 2.2-2.7 g/kg/day, while vegans consumed 1.9-2.5 g/kg/day. However, during the cutting phase, vegan bodybuilders had a protein intake of 1.6–2.2 g/kg/day, below the recommended guidelines for preserving lean mass of 2.3-3.1 g/kg/day. (Amatori et al., 2023)