Protein for Muscle & Fat Loss
How to stimulate & maximize muscle protein synthesis
I remember going to GNC and looking for a protein powder that had both whey and casein… this was many years ago now.
I asked the staff where they put it, and she asked me why I cared about whey and casein. “Protein is protein.” she explained, “We have almond bars here that are great sources of protein.”
I actually couldn’t believe my ears. I didn’t mean to be disrespectful, but I probably had a blank stare on my face for a couple seconds before asking if she had a manager around.
I wasn’t going to complain, I literally wanted to know where the whey protein was. Also, I am severely allergic to almonds. Her response? “I am the manager.”
Well, I thanked her and went on looking for whey and casein.
Now, to be clear, whey and casein might not be my choice today - but that’s not exactly the point of this article.
A lot of trainees understand these basic concepts:
Protein is a macronutrient, “the building block to all cells”
You need adequate protein to build muscle
Here is where there is a serious knowledge gap:
Protein is a category of nutrients, such as amino acids.
Each amino acid has specific and sometimes profound effects on our physiology.
Some of these amino acids are essential, others essential under certain conditions, and others are not essential.
L-Leucine is one essential amino acid that, aside from being essential, is particularly relevant for building muscle and strength.
Why? Because L-Leucine is literally the key that turns the ignition on for muscle protein synthesis.
The Leucine Threshold
Two processes occur at varying degrees in your body: muscle protein breakdown and muscle protein synthesis.
In other words, your body is breaking down and building muscle at various degrees all the time.
Obviously, we want to maximize the net amount of muscle protein synthesis.
Two major tools to accomplish this are exercise and protein intake.
In fact, even when calories are equal, you will lose more weight and more of it will be fat when you optimize protein intake.
That is because protein stimulates muscle growth and is essential for adapting to strength training. Protein is also more thermogenic than other macronutrients; it requires more energy to digest protein and so the net energy intake will actually be lower for the same number of calories.
But remember, protein is a category of nutrients. It’s not protein in general that stimulates muscle growth, it’s leucine.
If you ingest 30 grams of protein, at least 2.5 grams of that must be from leucine or you will not stimulate muscle protein synthesis.
If we optimize leucine through natural food sources, we typically optimize protein intake in general. Supplementing leucine on it’s own will not have the same effect. It will turn the key to the ignition, but you need all of the essential amino acids to build and regenerate tissue.
There is more than enough leucine to stimulate protein synthesis, along with 25-30 grams of protein, in 4-5 ounces of beef or chicken.
Leucine becomes a specific concern for vegan athletes, since leucine is significantly lower in plant sources.
For example, quinoa is often touted as a great source of plant protein, as are peas and lentils.
It would take 300 grams (more than half a pound) of quinoa to meet the leucine threshold, which comes along with 1,122 calories and 207 grams of carbohydrates.
You could try about 2 pounds of peas to meet the leucine threshold, but that would also come with about 700 calories and 120 grams of carbohydrate.
Or we can eat about 350 grams of lentils, almost a pound. That be the most protein dense option, with only 406 calories and 46 grams of carbohydrates.
But still, all of those examples are a ton of food, come with a massive dose of fiber which you may or may not be able to tolerate, and they only meat the leucine threshold for one meal. If you can seriously eat nearly a pound of lentils in a meal, that is impressive.
And you’d still want other foods to meet other nutrient requirements.
Or you can eat about 3.5 ounces of beef or chicken and you’ll hit the leucine threshold… with 150 calories or less.
The Leucine Plan
Ideally, we want to stimulate protein synthesis 3-4 times per day in 3-5 hour increments to maximize net muscle protein synthesis.
One meal per day, even with equal amounts of protein, does not compare to 3 or 4 meals per day in terms of muscle growth.
The body cannot store essential amino acids for later use and so needs a supply from food - that’s why they are essential. Of course, the body could break down muscle for amino acids, but that defeats the purpose.
In other words, we need 3-4 leucine rich meals per day.
As you can see, meeting the leucine threshold at the optimal frequency is rarely done correctly in the Standard American Diet.
1 egg on a bagel? No.
2 ounces of turkey in a sandwich? No.
1 protein bar? Nope.
Add one of these options to your meals 3-4 times per day to stimulate muscle protein synthesis and provide ample amounts of essential amino acids:
4 ounces of sirloin steak
4 ounces of chicken
4 ounces of bison
4 large chicken eggs
1 scoop of Whey or Beef protein
20g of Essential Amino Acids (EAA) powder
Protein is essential for maximizing muscle growth and thus, maximizing fat loss when losing weight.
Protein of itself does not stimulate muscle growth, however - you need adequate leucine, which appears to be 2.5 grams.
30 grams of protein with at least 2.5 grams of leucine 3-4 times per day is a baseline for virtually anyone, regardless of age or weight, of course excluding medical conditions.
Optimal levels can be much higher depending on weight and training status. 1 gram per pound of body weight appears to be an optimal level although there is some contention regarding optimal intake.
Thank you for reading, now go build some muscle!
Daniel J Furtado, CPT, LMT, Owner of Honor Strength
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