Lesson 10, Topic 1
In Progress

Protein – The Building Block of Tissues: For Educators

Michael Bewley September 19, 2020


Protein-rich foods are the ‘builders’ that sereve as the bedrock for muscle growth, maintenance and repair.

When in Doubt, Protein Out

An athlete who fails to get enough protein will not grow nor be able to leverage their full athletic potential. That’s why athletes turn to protein powders, shakes and nutrition bars — they are quick and easy to consume and provide a near fat-free source of muscle supporting protein.

Though proteins get found in small amounts in many foods, athletes look to “animal-derived” foods like fish, poultry, pork, red meat, low-fat dairy, and eggs, for a full spectrum of essential amino acids required for muscle growth and repair. Amino acids are the building blocks found in protein foods, and they do just that – they build muscle. The athlete hoping to develop his or her body needs more protein than the inactive individual. Plus, the harder you hit the weights to improve your strength and size, the more protein you’ll need.

Protein-Rich Food Sources

When choosing protein-rich foods, pay attention to what comes along with the protein. The best animal protein choices are fish and poultry. If you are partial to red meat, stick with the leanest cuts, choose moderate portion sizes & make it an occasional part of your diet. Download the Critical Reload Food Sources Guide to review and post on your fridge for quick reference.

Protein Quick Tips Guide


Food Sources Guide 607.00 KB 169 downloads


Avoid A Catabolic State

While carbohydrates are indeed an essential aspect of sports nutrition, the body will fail to grow, to become bigger and stronger without sufficient protein. Protein is an essential nutrient and the most critical element in muscle repair. Failing to eat enough protein will prevent you from growing while setting off a cascade of undesirable events leading to impaired athletic performance. Called catabolic state, it’s a state of extreme fatigue which short-circuits athletic performance and promotes a loss of muscle. Eating the right amount of protein can keep the body well-nourished with its building blocks – amino acids – helping the athlete to stay in a growth state while avoiding catabolism.

Amino Acid Power

Besides building the body, amino acids prevent a loss in lean muscle in yet another way. As glycogen stores (the body’s storage reserves of carbohydrates) fall, the body begins to burn amino acids. If protein intake is insufficient, lower glycogen stores set off a chain of events that cause muscle breakdown and loss! Mostly, muscles that are made up of amino acids are torn down and burned as fuel. Providing your body with enough protein each day will ensure muscles are rarely – if ever burned – even if glycogen levels plummet.


  1. Blake, J. (2014). Nutrition & You, 3rd Edition. Retreive from
  2. Clark, N (2013), Nancy Clark’s Sports Nutrition Guidebook. Retrieve from
  3. Gastelu, et al, (2015) Specialist In Performance Nutrition: Weight Control, Fitness, and Performance Nutrition. International Sports Science Association. Retrieve from ISSA Website.
  4. US Anti-Doping Agency: Nutrition Guide. Retrieve PDF file from USADA website.
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