Any fitness-oriented guy or gal out there already knows about the role of protein as a crucial nutrient for building lean mass. While it’s true that whole foods should be responsible for the bigger part of your protein intake, taking in some extra nutrition in the form of supplements can make a great difference in your results. Protein is made up of many amino acids that serve different purposes and they can be found in different amounts in different protein sources, which makes it quite challenging for aspiring bodybuilders to keep track of them all.
To help you understand amino acids better and make wiser choices in terms of your muscle-building supplementation, we’ve created this list of 14 important protein-building amino acids and their functions. Some of them are nonessential, which means that the body can produce them on its own, while the others have the status of essential amino acids and have to be obtained from food sources, and maintaining an adequate intake of both types is guaranteed to both enhance the gains from your gym efforts and keep your health in prime shape.
Non-essential amino acids
#1. Alanine
One of the simplest amino acids in terms of molecular structure, alanine helps the body convert the simple sugar glucose into energy and eliminate toxins from the body, and it also protects cells from damage caused by intense aerobic activity. Its counterpart, beta-alanine, a precursor to carnosine, is even more powerful at generating lean muscle and increasing strength and power.
#2. Asparagine
Asparagine is the amide of aspartic acid and was originally derived from asparagus juice. It plays a role in maintaining normal liver function, especially for synthesizing other amino acids, and keeping the nervous system healthy. Low levels of asparagine can result in the inability to properly synthesize and excrete urea, a waste product of excess dietary protein.
#3. Aspartic acid
Besides helping every cell in the body work, the most important task for this amino acid is helping the body create methionine, threonine, isoleucine and lysine. In addition, adequate amounts of aspartic acids are required for the needs of energy production and balanced hormonal activity.
#4. Cysteine
Cysteine is a sulfur-containing amino acid which is a constituent of many enzymes and plays a vital role in the synthesis of glutathione. In addition, it helps protect the body against cellular damage by free radical compounds and enhances the elimination of harmful chemicals from the tissue.
#5. Glutamine
Glutamine, an amino acid that makes up 61% of the skeletal muscle in your body, is the primary transporter of nitrogen into muscle cells. Glutamine is vital for gastrointestinal health, and it also plays key roles in protein metabolism, catabolism prevention and growth hormone production. In short words, this powerful amino makes your muscles grow, supports fat burning and enhances recovery.
#6. Glycine
Besides being one of the amino acids that make up creatine, glycine acts as a neurotransmitter involved in protein synthesis. Research suggests that supplementing with glycine can increase growth hormone production and muscular strength. It can also prevent muscle loss, cardiovascular disease and cellular mutations, while enhancing flexibility and range of motion.
#7. Tyrosine
The body makes tyrosine from another amino acid called phenylalanine, and in turn, tyrosine assists the production of hormones such as norepinephrine and thyroid hormones. Tyrosine can increase metabolism and energy levels, improve mood and enhance mental performance, while low levels of tyrosine lead to mood and sleep disorders.
Essential amino acids
#8. Arginine
Arginine is a basic amino acids that is a constituent of most proteins and gets converted into nitric oxide in the body, which makes it vital for cardiovascular health and muscle building goals. Increased levels of nitric oxide translate to increased blood flow to the muscles, which significantly enhances muscle performance and growth. In addition, studies have concluded that arginine can increase growth hormone levels.
#9. BCAAs
BCAAs (branched-chain amino acids) include isoleucine, leucine and valine are mostly used for gaining mass because of their powerful effects of protein synthesis. In fact, researchers believe that these amino acids are essential for stimulating muscle growth and prevention of catabolism. More specifically, BCAAs can help you increase the duration of your workouts, reduce fatigue and fire up your metabolism, thereby enhancing fat loss. The greatest benefit of supplementing with BCAAs lies in their ability to maintain muscle mass in terms of a calorie-deficit diet, which is very important for competitive bodybuilders.
#10. Histidine
Together with beta-alanine, histidine assists the production of carnosine, one of the most important anti-aging compounds found in the body. Histidine is also involved in the production of histamine, a compound that acts as a neurotransmitter, plays a part in local immune responses and increases nitric oxide production. Adequate levels of histidine are essential to both mental and physical health.
#11. Lysine
Lysine is another one of the building blocks of protein that’s essential for muscle growth, energy production and maintaining bone density and cardiovascular health. In addition, lysine has been proven to reduce anxiety levels and increase serotonin levels in both humans and animals.
#12. Tryptophan
Tryptophan is an amino acid that should be avoided around workout time since it increases fatigue. The body converts tryptophan into niacin, a B vitamin that plays a role in the synthesis of serotonin, which is a neurotransmitter that influences sleep and melatonin levels. This is why tryptophan can act as an effective sleep aid and a mild antidepressant. In addition, carbohydrates amplify the drowsy effects of tryptophan.
#13. Methionine
Like most essential amino acids, methionine plays an important role in many cell functions. Its primary purpose is to build protein, assist creatine production and maintain liver health. A methionine deficiency can lead to inflammation of the liver, anemia and depression.
#14. Phenylalanine
Phenylalanine is involved in the synthesis of ephinephrine, norepinephrine and dopamine, which are key neurotransmitters that influence the functioning of almost all systems and processes in the body. The body converts phenylalanine into tyrosine, an amino acid that plays a part in protein synthesis. Insufficient levels of phenylalanine lead to lack of energy, depression, memory problems and lack of appetite.
