What are the best protein sources for stimulating a maximal response of muscle protein synthesis following exercise?
Based on the current literature animal based protein sources are more potent at stimulating muscle protein synthesis compared to plant based proteins sources such as soy and wheat protein.
However there is still much to learn about other types of plant based protein sources such as mace, lentil and quinoa.
If you are looking for the most potent stimulator of muscle protein synthesis and you are not a vegan (or have food sensitivities), then whey, casein and milk proteins are your best choice.
Dr Witard has also written a nice blog on the best source of protein for building muscle: "Meat or Plants, based on the current evidence."
The key paragraphs:
"The reason why animal proteins are generally considered “higher quality” when it comes to building muscle is down to the type of amino acids they contain. Amino acids, in particular one called leucine, are thought to be key to driving muscle protein synthesis. In general, animal proteins have a higher proportion (9%-13%) of leucine than plant proteins (6%-8%). Plus, animal-based proteins usually contain all nine essential amino acids whereas most plant-based proteins are missing one or more of these amino acids.
There are exceptions such as maize protein, which boasts a 12% leucine content, and quinoa, which has a full complement of all essential amino acids. So it may be that certain plant proteins are just as effective as so-called “higher-quality” animal proteins.
We can potentially increase the “quality” of a plant-based proteins by fortifying them with extra leucine, combining different sources to make sure the food has all essential amino acids, or simply increasing the recommended amount of a plant protein source. As a note of caution, the latter option could require as much as 60 grams of certain plant proteins (for example seven large potatoes) – a dose that some people may struggle to consume.
The search continues for a more sustainable and environmentally friendly source of protein that can offer similar muscle-building potential to animal proteins. But based on currently available evidence, vegan bodybuilders will have to pay particular attention to their diets to achieve the same results."