Performing on a Plant Based Diet

By Heidi Strickler | June 24, 2019, 5 p.m. (ET)

Plant-based diet

"Where do you get your protein?”

This is likely the most annoying question a plant-based athlete receives from meat-eating acquaintances. The assumption that animal-based foods are the only protein source is a timeless and global misconception. In fact: 

  • One cup of cooked broccoli or spinach has as much protein as a medium egg (6 grams)
  • Spirulina, a blue-green algae, is the most protein-dense food on the planet by weight
  • 3 tablespoons of hemp seeds have equal protein (10 grams) to ½ cup Greek yogurt, plus 6 grams of omega-3 fatty acids

In the United States, the recommended daily allowance (RDA) for protein is 0.8 grams of protein per kilogram of body weight. However, this recommendation is meant to simply maintain basic bodily functions, and daily protein intake should be higher for most people. Research shows that endurance athletes need approximately 50% more protein than their sedentary counterparts (1), or 1.2 - 2.0g/kg protein daily, depending on training phase, weight goals, diet, gender, and age (2). Females, vegans and those looking to lose fat and gain lean muscle fall toward the higher end. 

Plant Protein 101

Amino acids are the building blocks for protein. Of the 20 amino acids, your body can make 11 of them — these are known as non-essential amino acids. The other nine are termed essential amino acids — they cannot be made by the body and must be consumed through foods. 

Animal foods (meat, dairy, eggs) contain all essential amino acids in roughly equal amounts. Plant foods such as quinoa, buckwheat, spirulina, soy, hemp, chia, hummus, and Ezekiel® breads also contain all nine, but most plant foods are lacking in at least one essential amino acid. While you don’t need all amino acids in every bite of food, achieving and maintaining whole body protein synthesis requires meals and snacks that include a variety of plant-proteins, including whole grains, legumes, nuts, seeds, and vegetables. 

Lysine is the only essential amino acid that is hard to obtain on a vegan diet because it exists in plants in very small amounts. Lysine is a precursor to carnitine, a key molecule in beta oxidation (the conversion of fatty acids into energy) (3). Carnitine also helps remove toxins from muscle, lowers cholesterol, and aids in the production of collagen — a protein found in bone, cartilage, tendons, ligaments, and skin. 

A mixed diet that includes meat, eggs, and/or dairy provides 60 - 180milligrams per day of carnitine, whereas a vegan diet provides 10 - 12 milligrams (3). For this reason, vegan athletes specifically should focus on high-lysine plant protein sources. Foods richest in lysine include tempeh, lentils, sprouted tofu, amaranth, quinoa, pistachios, garbanzo beans (chickpeas), and pumpkin seeds. 

Protein and Performance

The average individual can get away with a suboptimal vegan diet; however, the increased demands from training and racing can lead to poor performance, recovery and health for a vegan athlete.

Specific risks can include:

  • Spikes and crashes in blood sugar, because plant protein sources contain more carbohydrate and less fat than animal proteins. This can result in metabolic inefficiency and diminished ability to use fat as fuel, plus less satiety and increased sugar cravings.
  • Low energy availability (EA), in part due to high-fiber intake which reduces absorption of calories and nutrients. EA is the amount of energy left for basic bodily functions after exercise energy expenditure is subtracted from energy intake. Low EA can harm bone mineral density, hormone function, immunity and menstrual function, among other health issues (4).
  • Micronutrient deficiencies, including iron, zinc, vitamin B12, omega-3 fatty acids (EPA/DHA), calcium, and vitamin D. This is due to exclusion of key nutrient sources and decreased absorption due to high-fiber load (4).
  • Poor recovery, due to the exclusion of high-leucine foods (present in dairy foods). Leucine is a branched chain amino acid and is critical for exercise recovery. Athletes, especially females, should get 3 grams of leucine within 30 minutes of intense or prolonged exercise.
  • Diarrhea, especially while running, related to high-fiber intake.
  • Plant-based athletes who deal with gastrointestinal issues should consult with a registered sports dietitian about meal type and timing. 

Plant Pro Tips

Here are some tips for vegan athletes:

  • Eat a variety of plant-proteins throughout the day, including high-lysine sources, and ensure you are getting at least two sources with snacks and at least three with meals. Soak and sprout grains, legumes, nuts and seeds when possible.
  • Know roughly how much protein you need based on your goals, and plan accordingly (talk to a registered sports dietitian).
  • Optimize recovery by using a blend of plant-proteins to help reach your leucine needs after exercise.
  • Supplement strategically and intelligently. Have the appropriate blood work done and speak to a registered sports dietitian.
  • Consume a diet that is rich in iron. Include vitamin-C rich foods each meal to enhance iron absorption. Prioritize your highest iron foods at least 2 hours after exercise. Exercise increases the hormone hepcidin, which impedes iron absorption. 

A Day in the Plant-Based Life

The following sample meal plan provides a variety of lysine-rich plant-proteins, pairs high-zinc and iron foods with vitamin C and meets >100% daily requirement for vitamin B12, calcium and omega-3 fats.

  • Breakfast (pre-training): Oats or quinoa with pumpkin seeds and pistachios, molasses (for iron), and berries (for vitamin C). Add a high-protein nut milk or soy-free, plant-protein powder for extra protein.
  • Post-Training Snack: chia pudding or a smoothie with high-leucine protein powder and fruit.
  • Lunch: A hearty salad with leafy greens (kale, spinach or bok choy for iron and calcium), plenty of vegetables (beets for nitrates, peppers for vitamin C), chickpeas and organic tempeh, avocado (for omega-3 fats), and nutritional yeast (for vitamin B12).
  • Snack: sourdough bread or veggie sticks with hummus; or apple, banana, or sprouted bread or wrap (such as Ezekiel®) with nut butter and hemp seeds.
  • Dinner: Bean and lentil chili with tinned tomatoes and sweet potato. Roasted Brussels sprouts or broccoli on the side (an extra protein boost plus calcium and vitamin C).

Want athlete-focused plant-based recipes? Check out Heidi’s “Plant-based Metabolic Efficiency Recipe Book” here

References 

1. Wooding DJ, Packer JE, Kato H, West DWD, Courtney-Martin G, Pencharz, PB, Moore DR. Increased protein requirements in female athletes after variable-intensity exercise. Med Sci Sports Exer. 2017;49(11):2297-2304.

2. Thomas DT, Erdman KA, Burke LM. Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: nutrition and athletic performance. J Acad Nutr Diet. 2016;116(3):501-28. 

3. Rebouche CJ. Carnitine. In: Shils ME, Olson JA, Shike M, Ross AC (eds). Modern Nutrition in Health and Disease, 9th Edition. Lippincott Williams & Wilkins, New York, 1999, pp.505-12.

4. Fuhrman J and Ferreri DM. Fueling the vegetarian (vegan) athlete. Curr Sports Med Rep. 2010;9(4):233-41. 
Heidi Strickler, RD, CSSD, METS I, ISAK I is a Registered Sports Dietitian with eNRG Performance. An avid endurance athlete, triathlete, and ultra-runner herself, she has a passion for providing nutrition coaching to endurance athletes. She also specializes in plant-based nutrition, female physiology, and collegiate athlete nutrition. In July, she will graduate with a Master’s degree in Sports Nutrition from Liverpool John Moores University in England, United Kingdom. Find out more about Heidi at www.enrgperformance.com.