What Are Amino Acids Good for When It Comes to Fitness?

Your client says that other gym-goers are talking about amino acid supplements. Now they’re wondering if they should take one too. 

Depending on your state’s rules, some nutrition advice is outside your scope of practice. But you can usually provide the basic information as to why people might take this type of supplement. This requires knowing the benefits that amino acid supplementation can provide.

What Are Amino Acids Good for in Fitness?

The National Institutes of Health reports that sports nutrition supplements contain many ingredients (1). One is amino acids. This is because these acids contribute to fitness in several different ways.

Healthier Muscle Tissue and Function

An amino acid is a molecule that, when combined, forms protein. Protein is important to muscle tissue health. It works by supporting tissue growth (muscle protein synthesis). Protein also assists with repairing muscle tissue if it becomes damaged. Amino acids help regulate skeletal muscle function. 

Greater Muscle Growth

In one eight-week study, older participants engaged in low-intensity resistance training. Some took leucine and the rest served as a control. The leucine group increased their muscle mass more than the no supplement group. They also had greater improvements in handgrip strength. (2)

Enhanced Muscle Recovery

The amino acid leucine promotes post-exercise recovery according to a 2020 study. In this study, a leucine supplement improved muscle strength during exercise recovery. (3) This amino acid works by enhancing myofibrillar protein synthesis. This form of protein synthesis is important for muscle repair. 

Reduced Muscle Soreness

Amino acids can also help reduce muscle soreness. A 2019 meta-analysis looked at eight different studies. Each one involved branched chain amino acids and delayed onset muscle soreness (DOMS). Researchers concluded that the amino acid supplements reduced DOMS better than a placebo. (4)

Improved Sports Performance

Research explains that amino acids can help improve performance. They do this by supporting protein synthesis. They also aid in recovery. This allows athletes to do their best during training and competitions. Its findings are in Nutrition and Enhanced Sports Performance. (5)

Better Weight Loss Effects

Amino acids may help support weight loss. How they do this is up for debate. Some suggest that the acids boost fat metabolism. Others feel that their power lies in their ability to increase muscle mass. And the more muscle mass you have, the more calories you burn throughout the day. More theories are that amino acids stimulate growth hormones and block fat storage.

Extra Amino Acid Benefits

Amino acids aren’t just good for muscle health. They provide a variety of other health benefits as well.

One of these benefits is stronger immune function. When your immune function is good, your body can fight off the latest bug. Strong immune function is also important for avoiding disease. For instance, some studies have linked amino acid intake with a lower risk of autism. (6)

Another benefit of amino acids is greater digestive health. The body uses these molecules to break down the foods we eat. By consuming the amino acids we need, we can create a healthier gut.

Different Amino Acid Types

Although we talk about amino acids as if they’re all the same, they’re not. Amino acids can be split into three different categories—essential amino acids, nonessential amino acids, and conditional amino acids.

Essential amino acids: The human body cannot make this type of amino acid on its own. So, the only way to get essential amino acids is through diet. There are nine essential amino acids. They are: 

• histidine

• isoleucine

• leucine

• lysine

• methionine

• phenylalanine

• threonine

• tryptophan

• valine 

Branched chain amino acids also fall into this category. A branched chain amino acid (BCAA) contains three of the essential amino acids. They are valine, leucine, and isoleucine.

Nonessential amino acids: A nonessential amino acid is an amino acid that our body can make. So, if we don’t this type of amino acid from food, we’ll produce it on our own. The 11 nonessential amino acids are:

• alanine

• arginine

• asparagine

• aspartic acid

• cysteine

• glutamic acid

• glutamine

• glycine

• proline

• serine

• tyrosine

Conditional amino acids: An amino acid in this category is only needed if you are sick or under a lot of stress. In times such as these, a conditional essential amino acid may help. Amino acids falling in this category include:

• arginine

• cysteine

• glutamine

• tyrosine

• glycine

• ornithine

• proline 

• serine

Ways to Increase Amino Acid Intake with Food

You can increase amino acid intake by eating certain foods. If a food contains every essential amino acid, it is a complete protein. Animal protein sources are a complete protein. Does your client’s daily protein intake include meat, eggs, and dairy? If so, they’re likely getting all nine essential amino acids.

If your client gets most of their dietary protein from plants, they may be missing some of the essential amino acids. Pairing plant protein sources together ensures that they get all the amino acids they need. They may pair nuts with whole grains, for instance, to create a complete protein. Or they might pair beans with seeds.

That said, some plant-based foods are a complete protein. Quinoa is one. Chia seeds and tempeh are two more.   

Another Alternative: Amino Acid Supplementation

Research explains that, sometimes, eating protein isn’t enough. (7) You may not get each amino acid that your body needs through diet alone. That’s why some people rely on amino acid supplements. A 2019 study looked at supplement use by high-performance athletes. It found that an amino acid supplement is the second most common. A protein supplement was the first. (8)

Several types of amino acid supplements exist. You can buy an essential amino acid supplement, a BCAA supplement, and more. A nutritionist can help determine which one is best. 

How Much Amino Acid Do You Need?

There is no one-size-fits-all recommended amino acid intake. Instead, the amount of each amino acid needed depends on body weight.

An article in the journal Amino Acids talks about essential amino acid intakes. Their recommendations are as follows (9):

• histidine – 11 mg per kilogram of body weight per day

• isoleucine – 15 mg per kilogram of body weight per day

• leucine – 34 mg per kilogram of body weight per day

• lysine – 31 mg per kilogram of body weight per day

• methionine – 15 mg per kilogram of body weight per day

• phenylalanine – 27 mg per kilogram of body weight per day

• threonine – 16 mg per kilogram of body weight per day

• tryptophan – 4 mg per kilogram of body weight per day

• valine – 19 mg per kilogram of body weight per day

Remember that the essential amino acids must come from the diet. The body cannot make them. Aiming for these amounts can help ensure that one’s essential amino acid needs are met.

Who Should Take an Amino Acid Supplement?

If someone is not getting an adequate intake of amino acids in their diet, they may want to take a supplement. This includes individuals following a vegan diet. This person may need an amino acid supplement because most plant-based foods are incomplete proteins. 

BCAA supplementation may be beneficial for athletes. Among the benefits are optimized performance and better recovery. An example of the latter is reduced muscle soreness.

The only way to know for sure is to look at the client’s diet and determine if they’re getting their suggested intake. A nutritionist can assist with this. Their dietary analysis can help determine if amino acid supplementation is needed. 

You can also provide your clients nutritional knowledge as a Certified Nutrition Coach. This certification teaches you how to help clients set and meet nutrition and wellness goals. This helps ensure that all your clients meet their nutritional needs. 

References

1. U.S. Department of Health and Human Services. (2022, June 2). Office of dietary supplements - dietary supplements for exercise and athletic performance. NIH Office of Dietary Supplements. Retrieved October 21, 2022, from https://ods.od.nih.gov/factsheets/ExerciseAndAthleticPerformance-HealthProfessional/ 

2. Yoshimura, Y., Bise, T., Shimazu, S., Tanoue, M., Tomioka, Y., Araki, M., Nishino, T., Kuzuhara, A., & Takatsuki, F. (2019). Effects of a leucine-enriched amino acid supplement on muscle mass, muscle strength, and physical function in post-stroke patients with sarcopenia: A randomized controlled trial. Nutrition, 58, 1–6. https://doi.org/10.1016/j.nut.2018.05.028 

3. Waskiw-Ford, M., Hannaian, S., Duncan, J., Kato, H., Abou Sawan, S., Locke, M., Kumbhare, D., & Moore, D. (2020). Leucine-enriched essential amino acids improve recovery from post-exercise muscle damage independent of increases in integrated myofibrillar protein synthesis in young men. Nutrients, 12(4), 1061. https://doi.org/10.3390/nu12041061 

4. Fedewa, M. V., Spencer, S. O., Williams, T. D., Becker, Z. E., & Fuqua, C. A. (2019). Effect of branched-chain amino acid supplementation on muscle soreness following exercise: A meta-analysis. International Journal for Vitamin and Nutrition Research, 89(5-6), 348–356. https://doi.org/10.1024/0300-9831/a000543 

5. Martínez Sanz, J. M., Norte Navarro, A., Salinas García, E., & Sospedra López, I. (2018). An overview on essential amino acids and branched chain amino acids. Nutrition and Enhanced Sports Performance, 509–519. https://doi.org/10.1016/b978-0-12-813922-6.00043-6 

6. Singh, S., Sangam, S.R., Senthilkumar, R. (2020). Regulation of Dietary Amino Acids and Voltage-Gated Calcium Channels in Autism Spectrum Disorder. In: Essa, M., Qoronfleh, M. (eds) Personalized Food Intervention and Therapy for Autism Spectrum Disorder Management. Advances in Neurobiology, vol 24. Springer, Cham. https://doi.org/10.1007/978-3-030-30402-7_24 

7. Kamei, Y., Hatazawa, Y., Uchitomi, R., Yoshimura, R., & Miura, S. (2020). Regulation of Skeletal Muscle Function by Amino Acids. Nutrients, 12(1), 261. https://doi.org/10.3390/nu12010261 

8. Baltazar-Martins, G., Brito de Souza, D., Aguilar-Navarro, M., Muñoz-Guerra, J., Plata, M. del, & Del Coso, J. (2019). Prevalence and patterns of dietary supplement use in elite Spanish athletes. Journal of the International Society of Sports Nutrition, 16(1). https://doi.org/10.1186/s12970-019-0296-5 

9. Blachier, F., Blais, A., Elango, R. et al. Tolerable amounts of amino acids for human supplementation: summary and lessons from published peer-reviewed studies. Amino Acids 53, 1313–1328 (2021). https://doi.org/10.1007/s00726-021-03054-z