Plant-Based Nutrition for Endurance Training

What is a plant-based diet?

There are a variety of plant-based diets out there, all of which exclude animal products to different degrees. Depending on which foods you choose to exclude from your diet, there will be unique nutritional issues to keep in mind. So, what are the different plant-based diets?

Vegetarianism: This type of diet excludes all types of meat derived from animals, but you might still eat other food with animal origins such as milk, eggs and cheese. “Vegetarian” can also be used as a broader term for the more specific diets below.

Ovo-vegetarianism: This diet is distinguished from the one described above by including eggs, but excluding dairy products.

Lacto-vegetarianism: By contrast, lacto-vegetarians exclude eggs from the diet while consuming dairy.

Lacto-ovo-vegetarianism: Lacto-ovo vegetarians eat both eggs and dairy products, without consuming any types of meat.

Pescatarian: Pescatarians follow a similar diet to the lacto-ovo vegetarian, with the addition of fish and seafood.

Vegan: When on a vegan diet, you exclude everything that has an animal origin and solely eat plant-based foods.

Advantages and disadvantages of a plant-based diet for endurance athletes

Eating a plant-based diet with plenty of vegetables, legumes and fruit is beneficial for overall health. It has been shown to decrease the risk of cardiovascular diseases, high blood sugar and other health problems (1).

However, people with a high energy expenditure can find it difficult to take in enough energy on a plant-based diet. Vegetables and fruit have a low energy density and are often high in water and dietary fiber. As a result, you need to eat larger volumes or understand how to best combine these foods to get enough energy. Some might find it difficult eating these larger amounts, since a diet rich in dietary fiber will also make you feel full for longer than a low-fiber diet (2). If you have a high energy requirement or a hard time eating large servings, a potential solution is to add extra healthy fats to your meals. This increases the energy amount with lower volumes of food. Examples of healthy fats include olive oil, canola oil, avocado, nuts and seeds.  

A plant-based diet (if well balanced) is also naturally high in dietary fiber. Fiber is generally good for you, since it helps keep blood fat and sugar levels low. However, a large amount of dietary fiber, especially if you’re not used to it, can cause some discomfort. If you’re new to eating a higher amount of dietary fiber, try to increase your intake slowly. Eat regularly and make sure to drink enough water so that your body has time to adapt to it. 

Protein

There’s a common misconception that it’s difficult to get enough protein from a plant-based diet, especially when working out a lot. Truthfully, it is not as hard as you might think – you just need to be a bit more strategic. Protein takes on many important roles in the body, impacting the hormones, enzymes and immune system, as well as building and recovering the muscles. It is recommended to eat at least 0.83 grams of protein per kg of body weight (or 0.37g per lb) each day to meet your body’s needs (3). If you are a professional athlete or just train like one, your protein requirements will be a bit higher with a recommendation of 1.2-2 grams of protein per kg (0.5-0.9g per lb) of body weight (4). Protein exists in many different types of food. It’s not just found in eggs, meat, chicken and fish, but also in grains, legumes, nuts and seeds. As a result, it’s quite rare for an individual to lack in dietary protein, even when on a vegan diet. It’s more common that a person isn’t consuming enough energy in general. If someone has an energy deficit and their energy requirements aren’t being met, the protein in the diet will primarily be used up as energy instead of for its other functions. Therefore, if you have an energy deficit, it’s good to take in more protein to ensure the body still gets the amount it needs (5).

Protein & its complementary effect

There are some other things to keep in mind about protein apart from adequate energy intake. Protein consists of smaller building blocks called amino acids. There are about 20 different ones in total, nine of which are essential – this means we need to get them through the food we eat, since we can’t produce them in the body. Animal protein sources contain all nine essential amino acids, so if you are eating eggs, fish, meat or chicken, you will get all of them. Plant-based protein sources also contain essential amino acids, but they rarely have all nine of them. To complete the protein source, you can get all nine essential amino acids by combining two (or more) different plant-based food items in one meal (5). For example, legumes alone will not contain all essential amino acids. However, if you combine them with a grain like oats, they will complement each other to provide all nine. This might seem quite complicated, but truthfully it is not. As long as you eat a varied diet in line with your energy requirements, you can take in all required protein and amino acids without too much planning (1)

Vitamins & minerals to keep in mind

An adequate intake of vitamins and minerals is important, both for your general health and workout performance. When working out, even at a professional level, the recommended levels of vitamins and minerals are mostly reached when eating a varied diet according to your energy requirements (4). However, when excluding any food from the diet you need to make sure you are still getting its nutritional benefits elsewhere. Animal products are common sources of vitamins such as riboflavin, B6, B12, D, iron and calcium. When excluding animal products, you’ll need to take a little care in order to work those vitamins and minerals into your diet another way (6). A varied diet with different types of legumes, seeds, nuts, vegetables and grains covers most of these requirements. Also, today many plant-based products like soy and oat milk are enriched with vitamins and minerals to prevent any deficiencies. 

B12:

People on a strict plant-based diet won’t be able to take in enough vitamin B12, since its main sources are animal products like meat, fish and eggs. B12 does exist in plant-based products like fermented foods, but not in sufficient amounts (6). Therefore, if you follow a strict vegan diet it’s important to ensure you get enough B12 (1). 

Women and iron:

Iron is another thing to keep in mind when following an active lifestyle on a plant-based diet, especially if you are a woman of fertile age. Iron deficiencies are common for all women of fertile age, whether following a plant-based diet or not, but you are at higher risk if you don’t eat any animal produce. Iron does exist in plant-based foods including whole grains, beans and nuts, but this type is more difficult for the body to absorb than iron from animal products. It’s important to keep track of iron levels when following a plant-based diet, taking care to include extra iron sources like nuts, beans and whole grains (1). 

High-intensity endurance training on hard surfaces also leads to an increased breakdown of red blood cells (hemolysis), which may increase your need for iron (7). There are both inhibitory and stimulating factors that can affect the absorption of iron. For example, vitamin C and muscle meat in a meal enhance iron absorption. By contrast, phytates (found in i.e. legumes and grains) calcium and polyphenols (i.e. found in tea and coffee) inhibit the absorption (8).

If you’re taking part in endurance training while on a plant-based diet, it can be beneficial to keep these enhanced and inhibitor factors in mind. Have an orange (vitamin C) during or after your meal, since it enhances iron uptake. Additionally, make sure to include vegetable iron sources in all meals to prevent a deficiency.

Most importantly:

Whether you’re already following a plant-based diet or planning to in the future, make sure to eat a varied diet that meets your energy requirements. Remember, the more types of food you exclude, the more you’ll need to keep in mind to keep nutrition in balance. As always, if you’re unsure about nutritional planning consult your healthcare provider.

Don’t forget to try out one of our delicious plant-based recipes below! You’ll find plenty of them in the Lifesum recipe-tab if you search for ́ ‘Vegan”. We promise that you won’t be disappointed!

Green Curry Tofu

645 kcal, 20 min, 4 servings

28.2oz (800g) tofu

3 tbsp olive oil

4 tbsp green curry paste

1 1/2 cup coconut cream 

4 cup water 

9.2 oz (260g) rice noodles

6 cups (240g) baby spinach 

Method:

1. Cut the tofu into squares and fry in oil in a casserole pan for a few minutes.

2. Add coconut cream, water, green curry paste and stir.

3. Add rice noodles and spinach, boil for 2 minutes.

4. Season with salt and it’s ready to serve.

5. Add some lime and cilantro for additional flavor.

References

1. Livsmedelsverket. Vegetarisk mat för vuxna. 2019. https://www.livsmedelsverket.se/matvanor-halsa–miljo/kostrad-och-matvanor/vegetarisk-mat-for-vuxna/

2. Ru-Yi Huang, Chuan-Chin Huang, Frank B Hu; 2015. Vegetarian diets and weight reductions: a meta-analysis of randomized controlled diets. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4699995/

3. EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA). ‘Scientific Opinion on Dietary Reference Values for Protein’, EFSA Journal, vol. 10/no. 2, (2012), pp. 2557-n/a 

4. Sveriges Olympiska Kommitté (SOK). Kostrekommendationer för olympiska idrottare. 2016.

5 .Abrahamsson, L & Hambraeus, L. Protein. I Näringslära för högskolan, Abrahamsson, L., Andersson, A., Nilsson, G (red.),160-179. Stockholm: Liber AB, 2013.

6. Nordic Nutrition Recommendations. Vitamin B12. 2012. P.451. https://norden.diva-portal.org/smash/get/diva2:704251/FULLTEXT01.pdf

7. Burke, L., Deakin, V. Clinical Sports Nutrition. 5th ed. New York: Mc Graw Hill Education, 2015, 293.

8. Becker, W. Mineralämnen. I Näringslära för högskolan, Abrahamsson, L., Andersson, A., Nilsson, G (red.),180-222. Stockholm: Liber AB, 2013