With more knowledge available on plant-based diets, many individuals are opting to go meat-free and become vegetarians. While a vegetarian diet can be a healthier choice, it doesn’t always curtail or guarantee better performance, especially for athletes. Indeed, athletes new to vegetarian diets can consume poorly planned meals that increase the risks of nutritional deficiencies and decrease physical performance.
Some of these dietary pitfalls – including a lack of dietary variety, consuming excessive carbohydrates, and an over-reliance on meat-free processed food – can be addressed by understanding the nutritional requirements of a vegetarian athlete.
Richard Mallett, a Sports Science degree holder with years of experience in health and fitness, is a long-time vegetarian who has also spent time advising athletes (as a football coach) on how to approach the diet from a performance perspective.
A Macro-Nutrient Understanding
Holistically, athletes require their diets to have acceptable amounts of the major nutrient groups (proteins, carbohydrates and fats) that ensure optimal performance. For example, the recommended carbohydrate intake per day is between 3 to 12 grams per kilogram of body weight. For protein the recommended intake is 1.2 to 1.8 grams per kilogram, and it’s 1 gram per kilogram for fat.
These recommended intakes are not set in stone and can be adjusted to account for an athlete’s fitness level, the intensity of their training program, gender and age. Additionally, plant-heavy diets tend to have high levels of fibre (soluble and insoluble) that can provide other health benefits.
Flexible vegetarians can include eggs or dairy products in their diet, but strict observers can meet the maximum protein intake by adding foods such as soya, lentils, beans, nuts, seeds, cereals and whole grains.
It’s vital to note that most plant sources of protein do not have all the essential amino acids, which means that athletes must combine sources to gain the most benefits. These plant sources of protein don’t all have to be consumed in one meal but can be spread out over the day. Making sure that most of the day’s meals have a complete source of protein is recommended.
Inadequate iron in the body leads to excessive lethargy which can impact performance. Additionally, low levels of this nutrient can result in anaemia, which requires medical treatment. Plants generally have less iron compared to animal sources, and in terms of absorption by the body, iron from meat has higher absorption levels than that from plant sources. Furthermore, compounds such as polyphenols (present in coffee, herbs, spinach and tea), tannin (found in coffee and tea) and phytates (found in wholegrain cereals, oats, bran and tofu) can inhibit iron absorption.
To mitigate this, individuals are advised to consume iron-rich foods alongside vitamin C-rich foods, avoid tea or coffee with meals, and consume vegetables such as broccoli, kale, pak choi and peas, as these have lower phytate levels. Dried fruits, wholemeal toast and fortified cereal bars are also excellent sources of iron for an athlete.
Consuming foods with high phytate concentrations also affects the absorption of zinc, a nutrient that aids the proper functioning of the body’s immune system. Additionally, zinc levels from plant sources are much lower compared to animal sources. To combat this, adding wholegrain foods such as pasta and rice, bread, hard cheeses, lentils, beans, soya products, and nuts and seeds can provide the much-needed nutrient.
As an added measure, undertaking periodic blood tests provides detailed information on whether an athlete has the right levels of the essential nutrients. It’s a good idea and can go a long way towards identifying which foods to stock up on to meet all dietary requirements.