By Kristin Duyn, MSc
Why is protein so important?
Protein is essential for a wide range of bodily processes, most notably the synthesis and maintenance of muscles, enzymes, hormones, bones, cartilage, hair, and skin. Protein also helps dull hunger, preventing late night fridge raids, and provides an auxiliary fuel source for athletes to be used alongside fat and carbohydrate.
In the presence of adequate protein feeding, the combined effects of exercise and protein ingestion results in the formation of new proteins being made (referred to as protein synthesis) such that we can better withstand the physical demands associated with the next training session. It is these repeated changes in protein synthesis in response to every single training session that form the basis of how our muscles adapt and recondition to the demands of training (1). In order for such optimal training adaptation to occur, it is essential that protein is ingested in close proximity to the exercise stimulus given that protein rich foods and supplements contain the key amino acids that are used as the building blocks to make new proteins in our muscles (1).
Why should endurance athletes be mindful about their protein intake?
In the context of the endurance athlete, these amino acids are used to make the many hundreds of enzymes that are required in order to provide energy from the breakdown of carbohydrate and fat (1). The net result is that our muscles now contain more mitochondria (the factories where we produce energy during endurance exercise) and our exercise performance is significantly improved. It is advised that protein is consumed as 20-30 gram servings every 3-4 hours (1).
In a recent study, the recommended protein intake was determined to be approx. 1.83 g/kg/day, which is ~31–53% greater than previous recommendations for endurance trained populations (2). In a second study, the recommended intake came out to a range of 2.1-2.6g/kg/day for the 24-hour period post exercise (3). Based on this data, a 150lb (68kg) athlete undergoing endurance training needs about 140-180 grams of protein per day.
As intensity, frequency, and duration of training increases shoot for the higher end of the protein range. Skimp on this, and your body will borrow from muscle to meet its needs—undermining fitness growth. Fortunately, you should have no trouble meeting your protein quota if you eat a varied, whole-food diet.
- 2 Eggs : 12 grams
- 3 oz. Wild Atlantic Salmon (palm size): 22 grams
- 20 Raw Almonds: 6 grams
- Plain Low-fat Greek Yogurt: 25 grams
- 1 cup Cooked Quinoa: 8 grams
- 1 cup Cooked Lentils: 18 grams
- 3 oz. Cooked Tempeh (palm size): 17 grams
- 1 cup Cooked Steel Cut Oatmeal: 7 grams
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