Sport + Protein (Part I): How Much & What Kind?

*Photography by Raven Eye Photography. Athlete: Christopher Kuusselka (July 8, 2016)*

Bear with me for some background before we dive in...

Proteins are molecules that play many critical roles in our bodies. They are needed for the structure, function, and regulation of all our body tissues and organs – WOW, talk about responsibility!

Each individual protein is made up of a long chain of building blocks called amino acids, of which there are 20 different kinds. Our body can make some of these amino acids, but there are about 8 amino acids that are considered ‘essential’, meaning that we need to get them from the proteins (foods) that we eat.

*Image source: Bio-Social Methods Collaborative*

How much protein do you need?

The Recommended Dietary Allowance (RDA) for a typical adult is set at 0.8g/kg/d (for a 75kg adult, that is equivalent to 60g protein), however many nutrition experts agree that 0.8g/kg/d may be underestimating our needs as new techniques emerge to quantify protein requirements.

That being said, athletes are a different breed altogether. The American College of Sports Medicine, along with Dietitians of Canada and the Academy of Nutrition and Dietetics, recommend that endurance- or resistance-trained athletes consume significantly more protein in the range of 1.2-2.0g/kg/d to support enhanced muscle repair and growth (for a 75kg athlete, that is equivalent to 90-150g protein). Even higher intakes of daily protein may be required in the short term during intense training or during active weight loss.

Traditional protein recommendations for athletes focused on the total daily intake, however new research has shown that the type of protein as well as the timing/spread of protein intake throughout the day is just as important. More about that below…

Types/Sources of Protein {~g protein/100g food}:

•   red meat {29}
•   poultry {31}
•   fish/seafood {25}
•   eggs {12}
•   dairy foods (like milk, yogourt, cheese, and kefir) {4-24}
•   soy-based foods (like tofu, tempeh, edamame, dried soybeans, and miso) {12-39}
•   nuts & seeds (like almonds, cashews, chia and pumpkins seeds) {15-25}
•   legumes (like chickpeas, beans, and lentils) {8}
•   whole grains (like quinoa, millet and whole-grain bread) {4-11}

For more detailed lists of protein contents, look here, here, & here. Or search by single food by using Canadian Nutrient File.

*Photography by: A Little Nutrition/Ignite Nutrition Inc.*

Protein quality:

To assess a protein source, we can consider “protein quality”. A high quality protein is easily digested and contains all the essential amino acids in amounts that humans need to make body proteins. The Digestible Indispensible Amino Acid Score (DIAAS) proposed by the FAO (Food and Agriculture Organization) in 2013 ranks protein according to their quality.

Animal proteins such as meat/poultry/fish, dairy, and eggs contain all of the essential amino acids and have DIAAS scores above 100% (high quality), whereas vegetable proteins score below 80% (lower quality), with the exception of soy protein.

Plant-based proteins contain some of the essential amino acids, but are limiting in a few others. Plant proteins are each missing different essential amino acids, so if you eat a variety of plant-based proteins they will complement each other (i.e., the essential amino acid missing in one, will be present in the other). This is known formally as “protein complementation”. For example, the protein in legumes (beans, chickpeas, etc.) complements the protein in grains (barley, rice, wheat, etc.) and nuts/seeds.

When evaluating protein quality for muscle building we can also consider a protein’s leucine content. Leucine is one of the 8 essential amino acids and plays a key role in stimulating muscle protein synthesis. Foods that are naturally high in leucine are milk/yogourt (whey protein), egg white, red meat/poultry/fish and soy.

Vegetarian + vegan considerations:

Now that you’ve learned about food sources of protein and ‘protein quality’ you may be thinking that as a vegetarian or vegan athlete you could have more difficulty meeting your protein needs…This is actually quite a common concern, especially if your diet is not properly planned.

Here are a few reasons why vegetarian/vegan athletes may struggle to eat enough protein:

May need to eat larger volumes of food to get the same amount of protein (meat is more protein dense than legumes).
Many plant-proteins also contain a significant amount of fibre that can cause earlier feelings of fullness (early satiety) and therefore cause you to eat less.
If you are trying to limit your daily calorie intake, eating enough protein from vegetarian sources can be a challenge as they typically come with packaged with a significant amount of carbohydrate (ex: lentils) and fat (ex: nuts).
Need to make sure you consume a wide variety of plant-based proteins to ensure adequate protein complementation.
- Note: Protein complementation does not need to be done at the same meal. The assortment of proteins can be eaten over the course of the day. If you ate chickpeas for lunch and then had some raw almonds for your afternoon snack you would be covering your bases.
May need to eat more protein (~10% more) to achieve the same muscle protein synthesis due to the lower bioavailability of protein from plant-based foods. Aim for the higher end of daily protein target (1.6-2.0g/kg vs. 1.2-1.6g/kg).

Health + wellness:

Although it may be easier to meet your protein needs for sport performance, recovery and muscle maintenance with high quality animal-based protein, these types of protein also tend to also be accompanied by higher amounts of saturated fat and cholesterol, which can affect our heart health.

A recent study released earlier this month found that eating animal protein was associated with a higher risk for mortality, whereas eating plant-based protein was associated with lower mortality. These associations were apparent only in populations that also had at least one other unhealthy lifestyle factor such smoking, heavy alcohol intake, overweight, or physical inactivity. Animal protein did not appear linked to a higher mortality risk, nor was plant-based protein tied to a longer life for people with a healthy lifestyle.

The bottom line:

There are certainly many benefits for including more plant-based protein in your diet in terms of health and mortality. And there are also many benefits of consuming animal-based protein for athletes focused on exercise performance and recovery, and muscle protein synthesis.

If you are an athlete who relies mainly on animal-based protein, aim to add a few plant-based proteins into your daily eating habits. Try focus on lower-fat dairy, eggs, seafood, and lean meats/poultry and swap out your processed red meats for some hummus and stir-fried tofu!

If you are a vegetarian or vegan athlete, you can still meet your daily protein requirements for performance. However, you may need to do a little more planning depending on your goals, appetite, and calorie limits. This is where meeting with a Registered Dietitian may be helpful.