Protein synthesis: the physiological process for constructing proteins from amino acids. The overall goal for the typical weight lifter is to build lean tissue. For the cross training athlete, the goal could be maintenance of lean tissue. In either case, the protein synthesis process is the vehicle that gets the athlete to that point. Just like with any of the body's processes, there are requirements in terms of raw materials needed to facilitate the cellular tasks. Protein synthesis requires several. In previous posts, I've touched base on the need for cellular catalyst and glycogen replenishment. What I wanted to touch base on here was the most vital component: dietary proteins.

Proteins are made up of an assortment of amino acids bound together forming what is called a peptide chain. It is the arrangement of these individual amino acids that give the proteins their unique characteristics and roles. There are a total of 20 amino acids - 9 essential and 11 non-essential. Of these 20, the body has the ability to synthesize 11 of them. These are called non-essential amino acids, and the term is appropriate because they do not need to be ingested as the body can make them. The remaining 9 are considered essential because the body does not possess the ability to synthesize them. As a result, they must be ingested in order for the proteins to become functional as the building blocks for new tissues.

When proteins are ingested, the peptide chains are simplified in the GI tract. Once broken into small enough molecules, they are absorbed and enter the blood stream. Keep in mind, we do not have the ability to absorb whole proteins. As a result, they must be broken down into individual amino acids or short-chain peptides in order to be absorbed. Once absorbed, these amino acids and peptide chains make up what is called the amino acid pool.

The amino acid pool provides for cellular catalyst to "withdraw" what is needed for their respective tasks. For proteins to be constructed, all 9 essential amino acids MUST be present within the amino acid pool. This pool does not last forever, though. With a window of approximately 2-3 hours, if the amino acid chain is not completed with the "missing links", a chain reaction is set off that ultimately causes the body to go to any lengths to obtain the raw materials it needs to complete its current task. This means it must "rob" the essential amino acids from another cell; thereby, breaking it down and rendering it useless.

After such time period has elapsed, the excessive amino acids not being used for protein synthesis are then deaminated and used for synthesis of glucose. Whether this glucose is needed at the time or not does not matter. The body cannot store proteins; therefore, it must convert the excess to a substance that can be stored in order to achieve homeostasis. This glucose can then be stored as glycogen in the muscles or liver cells or as fat in adipose tissue.

So, now the question arrives of "how do we know if we're ingesting whole proteins or not? The labels on my foods only tell me the quantity of protein." Simple.. some examples of incomplete proteins are grains and legumes (beans). Typically, these protein sources conveniently contain what the other is lacking; therefore, they are considered "complimentary proteins". If you grub on some beans, they should be complimented with a grain like rice. This will complete the amino acid chain giving the pool and cells all 9 essential amino acids. Did you know that peanuts are actually not nuts? They are classified in the legume family along with beans. As a result, they also do not contain all 9 essential amino acids and should, therefore, be complimented with a grain such as wheat bread or oats. Examples of complete proteins would be summarized by anything that is of animal origin - dairy, meats, poultry, fish, etc.

So, the moral of the story is to focus on quality not quantity. A protein is not necessarily a protein in terms of being used for protein synthesis. If you're consuming incomplete proteins without complimentary sources within 2-3 hrs, do not count those proteins towards your daily protein intake. They will not be used to build or repair tissues and will, therefore, be used for energy purposes.