1 Formal Research Assignment: Veganism and High-Performing Athletes Briana Maniscalco Keiser University ENC 4313: Research Writing Dr. AnneMarie Fowler July 5, 2020 2 Veganism and High-Performing Athletes Over the past decade there has been a definite rise in vegans across the United States. In 2016 it was reported that 0.5% of the population were vegan. Fast forward to more recent studies, a drastic increase of veganism jumps to 6%, but, why the six-fold increase within a few years? A 2018 film, titled “Game Changers”, showcases several elite vegan-athletes and suggests that a plant-based diet reigns supreme to an omnivorous diet and can improve physical performance. Many athletes presented in the film have more recently made the switch to a plantbased diet and are supported by dieticians, physicians, personal trainers, and chefs to ensure their diets do not lack any necessary nutrients. Many of the essential nutrients such as vitamin b12, zinc, n-3 fatty acids and an adequate amount of high-quality protein cannot be found in plants alone. A vegan diet is not optimal for elite athletes because many plant-sourced protein and nutrients are far less bioavailable than that of animal products, elite athletes require an above baseline amount of these nutrients as well as additional supplements to enhance performance and recovery and the likely deficiencies without supplementation will be detrimental to performance and muscle mass over time. Plant sourced nutrients such as omega-3 fatty acids, calcium, vitamin D, iron, zinc, iodine, vitamin B-12 and riboflavin are found less plentiful in plants in comparison to animal products, or are not adequately absorbed in the body. Bioavailability is the portion of a nutrient that is absorbed by the body and is influenced heavily by the structure and chemical makeup of the food. Antinutritional factors are compounds that reduce bioavailability, digestibility, and absorption of plant and animal proteins and are naturally synthesized in plant foods such as beans, legumes, soybeans, and cereals. (Lynch, Johnston, & Wharton, 2018) Plants, in nature, have their own self-defense approach against insects and grazing animals by producing oxalic 3 acid and oxalates which poisons them over time. These antinutrients, like phytates, lectins and oxalates have the biggest conversation when looking at the mechanism of damage to gut health, depending on a person’s sensitivity and genetic predisposition, and occur predominantly in raw plant foods. (Popova & Mihaylova, 2019) As researchers and scientists learn more about plants and the growing assortment of popular diets, I believe it’s important to question the old, simplistic idea that if it’s found in nature it must be good for you without first understanding how your body functions, and how you can optimize your own health by individualizing a diet. According to Rogerson, “Plant-based protein sources are often incomplete, missing important essential amino acids such as leucine, and typically contain less Branched Chain Amino Acids (BCAA) than their animal-based equivalents” (2017) Systems for scoring amino acid composition, digestibility and quality of protein were first constructed in 1989. The Protein Digestibility Corrected Amino Acid Score (PDCAAS) was created and one of the most used, although it has many restrictions including the disregard of antinutrient factors. In 2011, a newer system called Digestible Indispensable Amino Acid Score (DIAAS) was created and is considered higher ranking than the PDCAAS. (Lynch, Johnston, & Wharton, 2018) When comparing both it seems that animal-sourced protein scores higher than plant sourced. On the PDCAAS, soy protein is comparable to whey protein at 1.0 to 1.0, but when factoring in antinutrient inhibitors through DIAAS, whey protein is superior with a score of 1.09 vs 0.91. This goes to show how much of the nutrient is lost due to fiber and the poor nutrient binding absorption. To make up for the low bioavailability, it is strongly suggested that vegan athletes seek to consume more of these foods, specifically protein than omnivores to avoid nutrient deficiencies and muscle breakdown. 4 When considering the high energy demand of an elite athlete, consequently, the low nutrient digestibility will be detrimental to performance and recovery. Strength and power training athletes have different nutrient and supplement needs than that of endurance athletes. Endurance athletes require a higher carbohydrate concentrated diet to replenish burned glycogen stores and fuel longer, high-intensity training and stabilize blood sugar levels, while strength and body building athletes will generally need more overall food consumption and “timing and distribution of protein consumption throughout the day are also important”. (Lynch, Johnston, & Wharton, 2018, p. 5) Yet, both require sufficient vitamins and minerals to maintain healthy muscles and bones for maximum potential performance output. Vitamin B12, zinc, and n-3 fatty acids, which are mainly found in animal products, are important for bone health. Vegans may be at greater risk of osteoporosis and fractures than omnivores especially when putting excessive stress and load on the bone through sports and exercise. (Veronese & Reginster, 2019) Within a plant-based diet, food choices tend to be low in fat, high in carbohydrates and high in fiber which could affect the absorption in some nutrients. Endurance athletes look to adopt a diet that could increase exercise capacity and anaerobic energy supply (Nebl, Haufe, Eigendorf, Wasserfurth, Tegtbur, & Hahn, 2019) and checklists that satisfy pre and post-training carbohydrate fueling, and adequate amount of iron. Whereas body builders or strength training athletes are interested in diets that maximize muscle mass and strength gains. “For athletes in heavy training, a plantbased diet with excessive fiber may result in insufficient low energy intake and potentially reduce enterohepatic circulation of sex steroid hormones.” (Larson-Meyer, 2018) A study done in 1999, reported an increase in mean type II muscle fiber size and increased hemoglobin and hematocrit in omnivorous diet groups in comparison to a vegan diet group. While another study done in 2012 revealed a vegetarian diet with low protein was acutely higher in oxygen 5 consumption. (Craddock, Probst, & Peoples, 2016) High quality protein consumption optimizes protein metabolism at a skeletal muscle level especially in older people whose muscles and bones are slowly degenerating. Plant based proteins have lower anabolic potential than animalbased proteins and therefore, are suggested to vegans, to increase protein intake. (Berrazaga, Micard, Gueugneau, & Walrand, 2019) A large survey of vegans said their average protein intake was 83g/d which, for an 80kg athlete, is 35% lower than the low end of the average. According to Craddock, Probst and Peoples, who reviewed seven randomized controlled trials and one cross-sectional study, there appeared to be no differences between a vegetarian based diet and an omnivorous diet in muscular power, muscular strength, anaerobic or aerobic performance. We can conclude that there may be favorable effects of a high carbohydrate diet for endurance athletes to fuel glycogen depletions during prolonged, high intensity training although this can be satisfied with a mixed diet. It is advised that all athletes consume an adequate amount of protein, fats, and carbohydrates but not to exceed caloric suggestions, by an overconsumption of calories due to a high carbohydrate ratio when trying to consume enough protein for recovery purposes, as this could be detrimental to performance as well. Equally important, is the supplementation needed to improve peak performance and prevent nutrient deficiencies outside of diet foods, whether you are an endurance athlete or body builder. Some supplements such as creatine, and beta alanine directly improve performance and should be considered to maximize potential benefits. Although some athletes take supplements in competitive sports to take advantage of getting ahead, some athletes use supplements to correct deficiencies, gain performance benefits, recovery from hard training sessions or optimize mass and body composition. (Maughan, Burke, Dvorak, Larson-Meyer, Peeling, Philips, & Engebretsen, 2018) For performance enhancing reasons, supplementation should only be 6 considered after a well-rounded diet and, a vegan diet must be supplemented to begin with. Outside of ethical reasons, if an athlete is looking to optimize performance and recovery, it would not make sense to take on a vegan diet to supplement more than half of the dietary needs. “A vegan diet is usually characterized by low intake of protein, creatine and carnitine, which could negatively impact performance.” (Nebl, Haufe, Eigendorf, Wasserfurth, Tegtbur, & Hahn, 2019) Creatine, mainly found in meat, fish, and poultry are not included in a vegan diet without supplementation. Research shows that creatine may be the most beneficial supplement in improving “short-term high-intensity exercise performance, muscle hypertrophy and maximal strength.” (Rogerson, 2017, p. 11) Similar to creatine, beta alanine, a precursor to carnosine, is shown to be lower in vegetarians and vegans due to the lower muscle carnosine levels. Beta alanine is sourced through meat and poultry and proper supplementation can lead to performance improvements by decreasing muscle fatigue and scavenging free radicals. (Rogerson, 2017) When used appropriately, these can enhance performance, but it is important to educate yourself with knowing what a specific diet lacks and how you can optimize nutritional needs to achieve maximum potential in training and recovery. This diet proves there are many limitations and deficiencies in nutrient absorption and proper macronutrient availability in food choices. This makes the long-term adoption of the diet very difficult to sustain and performance could suffer over time. It just does not make sense to eliminate a certain food source out of your diet when you are not able to receive essential nutrients to optimize performance, let alone health. A plant-based diet is growing in popularity, which is more recently, promoted by athletes who have adopted the lifestyle and lead the general population to believe that becoming a high-performing athlete is optimal on a vegan diet regardless of ethical and moral reasons. A nonpermanent approach to the diet, or a balance of an 7 omnivorous diet with a variety of food and micro and macro nutrient consumptions may provide benefits of optimal performance and recovery. References Berrazaga, I., Micard, V., Gueugneau, M., & Walrand, S. (2019). The Role of the Anabolic Properties of Plant- versus Animal-Based Protein Sources in Supporting Muscle Mass Maintenance: A Critical Review. Nutrients, 11(8), 1825. https://doi.org/10.3390/nu11081825 Craddock, J. C., Probst, Y. C., & Peoples, G. E. (2016). Vegetarian and Omnivorous Nutrition-Comparing Physical Performance. International Journal of Sport Nutrition & Exercise Metabolism, 26(3), 212–220. Larson-Meyer, E., PhD, RD, CSSD, FACSM. (2018). Vegetarian and vegan diets for athletic training and performance. Sports Science Exchange, 29(188), 1-7. Retrieved June 14, 2020, from https://www.gssiweb.org/docs/default-source/sse-docs/larsonmeyer_sse_188_v3.pdf?sfvrsn=2 Lynch, H., Johnston, C., & Wharton, C. (2018). Plant-Based Diets: Considerations for Environmental Impact, Protein Quality, and Exercise Performance. Nutrients, 10(12). https://doi.org/10.3390/nu10121841 Maughan, R. J., Burke, L. M., Dvorak, J., Larson-Meyer, D. E., Peeling, P., Phillips, S. M., Rawson, E. S., Walsh, N. P., Garthe, I., Geyer, H., Meeusen, R., van Loon, L. J. C., Shirreffs, S. M., Spriet, L. L., Stuart, M., Vernec, A., Currell, K., Ali, V. M., Budgett, R. 8 G. M., & Ljungqvist, A. (2018). IOC consensus statement: dietary supplements and the high-performance athlete. Sport & Geneeskunde, 2, 19–40. Nebl, J., Haufe, S., Eigendorf, J., Wasserfurth, P., Tegtbur, U., & Hahn, A. (2019). Exercise capacity of vegan, lacto-ovo-vegetarian and omnivorous recreational runners. Journal of the International Society of Sports Nutrition, 16(1), 23. https://doi.org/10.1186/s12970019-0289-4 Popova, A., & Mihaylova, D. (2019). Antinutrients in Plant-based Foods: A Review. The Open Biotechnology Journal, 13(1), 68-76. doi:10.2174/1874070701913010068 Rogerson D. (2017). Vegan diets: practical advice for athletes and exercisers. Journal of the International Society of Sports Nutrition, 14, 36. https://doi.org/10.1186/s12970-0170192-9 Veronese, N., & Reginster Jean-Yves. (2019). The effects of calorie restriction, intermittent fasting and vegetarian diets on bone health. 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