The Simple Science Behind Protein Supplementation
We hear it all the time as athletes, fitness lovers, or people who simply want to live a healthier life: EAT YOUR PROTEIN!
This is one trend that we are glad is finally catching on as protein has some many benefits to performance and recovery, let alone being an essential macronutrient your body needs to function properly.
While going to food sources is always a great way to go, protein supplements are an easy (and delicious!) way to make sure you are getting enough protein in your day and are getting protein in sources your body can utilize the best.
The Bottom Line ---> The quality and bioavailability of your protein can influence how quickly your body can use it after a workout and high well it is absorbed to make sure you are getting full benefit of your post workout protein.
A well made protein powder can also offer muscle protein synthesis benefits greater than a regular dairy product because it resulted in higher plasma leucine and other essential amino acids that are important for the postprandial muscle response for muscle mass and strength growth.
So how do you know you are picking a quality protein?
Just walking into a supplement store is overwhelming at times because you see so many options: whey, casein, soy, pea protein, rice protein, blends, isolates, etc.
Knowing the benefits of certain types of protein can help you not only make a wise choice so you’re not wasting money, but also will help you choose the best protein for your goals.
Our favorite? Paleoethics' All Natural Grass Fed Whey.
Protein is obviously important for stimulation of muscle protein synthesis (We won’t go into all the details with that pathway, just enough to understand why your body needs certain protein qualities).
For years, pure Whey was always touted as the best way to go to stimulate muscle protein synthesis as it was the quickest digesting and thought to get into the muscles the quickest, making sure to hit that magic 30 minute anabolic window.
Luckily, we now know that digestion that occurs outside of 30 minutes after your workout is still beneficial for rebuilding, repairing, and recovering muscles.
However, recently more research has leaned more towards protein blends that may not cause as quickly of a rise in blood BCAA levels as pure whey isolate would, but did lead to sustained elevated levels of blood amino acids later into recovery.
FSR (fractional synthetic rate) remained elevated only in the a protein blend group versus a just whey group. mTORC1 signaling increased similarly between both proteins, except there was no increase in S6K1 phosphorylation in the just Whey group at 5 hours post-exercise.
What this is saying, is, blending protein sources with different digestion rates may show additional benefit by having just enough amino acid pool expansion to signal additional muscle protein synthesis while delaying all the amino acids from going into the muscle to have some in the pool for later.
Muscle protein synthesis occurs with at least 20 grams of protein, consisting of 8-9 amino acids and at least 1.8 grams leucine.
A fast, rapidly digested source causes a rapid and maximal increase in muscle protein synthesis, whereas a slowly digested source is more likely to cause a delayed, more prolonged response, at least in the post workout stage.
This fits perfectly if you buy a protein blend of WHEY and CASEIN to get the the quick digesting protein from the whey, and the slow digesting protein with the casein.
With blends, its preferred to have casein and whey together in comparison to other protein sources because together they have all the essential amino acids in the amounts necessary to stimulate muscle protein synthesis and are easily absorbed by the body.
Because of a higher BCAA content, and rapid increases in blood amino acid concentrations, whey protein is often considered superior to other isolated protein sources such as vegetarian sources like soy or pea protein.
Whey is also a good source of leucine, the main amino acid to stimulate muscle protein synthesis.
Whey is about 10% leucine, or about 10 grams of leucine per 100 grams whey protein powder.
Higher leucine content stimulates the muscle protein synthesis pathway (mTOR), as long as total protein content is also adequate, making a serving of whey protein (usually 24-30 grams) a great source of this necessary leucine, as well as other amino acids.
While vegetarian protein powders do not have as high of leucine content as dairy options, that doesn’t mean soy protein is bad for you.
There are some benefits to soy, especially for those who are vegans.
Soy is the only plant protein that does contain all 9 essential amino acids in the proper amounts to support muscle growth, as well as fiber.
Soy does not have the high BCAA content whey protein does, which is a downside, but it does have high amounts of arginine and glutamine.
Studies have shown that both whey and soy are effective in helping with lean muscle growth and recovery from exercise. Soy protein does have a more gradual release than whey, so it could also be used to complement whey in a blend and there are studies to suggest that it does not have the same hormonal release (aka testosterone) effects as whey or have the same ability to blunt cortisol.
The other common vegetarian source of protein is pea protein.
While this can be another good option, it does not quite have the nutritional profile that animal based products like whey can casein do, such as digestibility and BCAA content. However, it can be a good allergy-free option if you need a dairy/lactose free option.
Bottom line, first step is making sure you are getting your necessary amount of protein in, as any protein source is better than no protein source.
After that, you can fine tune the details by analyzing leucine and other amino acid content of different protein powders.
In this review, animal based proteins, especially blended, like a blend of whey and casein came up superior for amino acid profile and having the ability to be both fast and slow digesting for optimal protein synthesis and absorption.
Getting that mix of protein sources can lead to better recovery, more satiety between meals, thus having an effect on body composition, and are usually very delicious!