Why Athletes Need Fats

Why Athletes Need Fats

05 Mar

Why Athletes Need Fats

But I thought fat makes you fat? Eh, there’s a bit more to it than that. In this post, we are going to discuss why we need fat and why it’s an important tool in an athlete’s diet. The points we will cover:

  • Types of fat and sources
  • How it interplays with hormones
  • How much you need for performance

What is fat?

Fat is one of three macronutrients we consume on a daily basis. It consist of organic molecules containing carbon and hydrogen atoms joined together in long groups called hydrocarbons. The arrangement of these hydrocarbon chains will determine the fat type.

There are three different types of fats we get from our diet:

Saturated Fat (A fat with no double bonds between the individual carbon atoms of the fatty acid chain) (too much may cause the cell membrane to be too rigid)



Coconut (oil, milk, shredded)


Dark Chocolate (70%+ cacao)

Fatty Beef, Lamb

Palm Oil

Whole Fat Milk, cheese, yogurt

Monounsaturated Fat (a fat with a single double bond between the carbons in the fatty acid chain)


Almonds (almond butter)

Avocado (guacamole)

Brazil nuts (high in selenium which is a powerful antioxidant, can’t over indulge in these as too much selenium can cause an negative effect on the system)

Cashews (cashew butter)

Egg yolk

Hazelnuts (hazelnut butter)

Macadamia nuts (macadamia nut butter)

Olives (olive oil)




Chicken and Duck Fat

Polyunsaturated Fat (a fat with two or more double bonds between the carbons in the fatty acid chain) (too much many cause the cell membrane to be to fluid)


Chia Seeds

Cod Liver Oil

Fish Oil


Grapeseed Oil

Hemp Seed

Pine Nuts


Sunflower seeds

*We can synthesize most fatty acids, but there are two we can’t make:

Omega 3 Fatty Acids (ALA, EPA, and DHA) - anti-inflammatory

-Improves cell membrane fluidity (a more fluid muscle cell membrane will increase insulin sensitivity; a more fluid brain cell membrane will improve the transmission of neurochemicals)

-Dilate blood vessels

-Lower inflammation

-Prevent blood coagulation and clumping

-Dilate airways

Omega 6 Fatty Acids ( LA, GLA, and AA) - pro-inflammatory

-Constrict blood vessels

-Increase inflammation

-Cause blood clotting

-Increase pain

-Constrict airways

Both are vital for our health and performance. Ensure you are getting enough in the diet either via foods and/or supplements. If supplementing with fish oil or algae oil, keep them in the refrigerator to minimize oxidation.


(signaling molecules produced by glands that travel via the circulatory system to regulate our behaviors and physiology)

Let’s talk about Cholesterol, an organic lipid (fat) molecule. While the mainstream media has placed cholesterol on the taboo list, human physiology is much more complex than one might imagine from reading a Webmd article. All steroid and corticosteroid hormones, including Vitamin D, are derived from cholesterol, which is biosynthesized by all animal cells. Our liver makes roughly 80% of the daily cholesterol we need while the other 20% is attained via the foods we intake. Our liver will tightly control this relationship adjusting production relative to how much is consumed and how much is needed. Worth noting, some people are genetically predisposed to having higher cholesterol levels, but that is outside the scope of this blog post. The hormones we derive from cholesterol:

Sex hormones:

Testosterone - primary male sex hormone - responsible for bone and muscle mass development

Estradiol - the major female sex hormone - helps to regulate the female reproductive cycle and development and maintenance of female reproductive tissues

Corticosteroid hormones:

Cortisol* - body’s main stress hormone - increases blood sugar production, suppresses the immune system, decreases bone formation (these become an issue when cortisol is “chronically” called upon)

Aldosterone - essential for sodium conservation and regulating blood pressure

Pregnenolone - precursor hormone to Progesterone, DHEA, Cortisol,

Progesterone - involved in menstrual cycle, pregnancy, embryogenesis,

DHEA - the anti-stress hormone, helps balance out cortisol, they are inversely related

*When our cortisol (main stress hormone) is chronically elevated, the body will increase cholesterol production, specifically Low-Density Lipoproteins (LDLs), in order to produce MORE of that hormone. Instead of looking at decreasing your cholesterol intake, it might be prudent to look at areas of your life where you can mitigate stress, bring the body back into balance to allow for more parasympathetic drive.

Proper synthesis of these hormones is predicated on the presence of cholesterol. While the liver will tightly control cholesterol production relative to how much is consumed, it still warrants adequate consumption in our diet. Additionally, in order for each step of the hormonal synthesis process to take place we need vitamin A. Why is this important? Vitamin A is a fat-soluble vitamin (along with D, E, K) meaning it needs to be consumed in the presence of fat to act as a transporter. Another important reason for adequate inclusion of fat in the diet to support transportation and synthesis of vital pieces for our hormones and by extension, our performance.

For those interested, Vitamin A is in high quantities of dark leafy green vegetables and other colored vegetables. To ensure it is absorbed appropriately, add some type of oil (olive, avocado, macadamia) or nuts along with some vitamin C, which helps improve iron absorption, via citrus fruits to help improve absorption of the vitamin and minerals in the vegetables. Lemon Juice and Olive Oil are always solid, and tasty, choices to add on a salad and now you know why.

How much fat intake do I need for performance?

While we now know that fat is an important macronutrient in our diet, how does it relate to our performance? If it’s so good, should it make up majority of our energy intake? Not so fast. The first question we have to answer is, what type of performance (or sport) are we looking at. The functional requirements of the sport will dictate what fuel sources are needed. When thinking about CrossFit, the functional demands of that sport require high amounts of training volume with varied degrees of intensity, favoring the side of “intensive” training. With that in mind, countless research studies have looked at what is optimal fueling for performance in more intensive based sports in comparison to endurance based sports. This quote provides a bit of insight into what the general consensus has been:

“Studies in which trained individuals have been exposed to a high fat diet (>60-65% of dietary energy) for 5-28 days show markedly higher rates of fat oxidation and reduced rates of muscle glycogen use during submaximal exercise compared with consumption of an isoenergetic high carbohydrate diet…However, examination of the performance outcomes from these studies shows either a lack of a performance benefit or methodological/design flaws that require a conservative and cautious interpretation of the results…”

For more specifics on fueling for CrossFit, see my blog post here: Why CrossFit Athletes Need Carbs

When looking at sport performance in CrossFit, fat plays a very important piece in the diet but it plays more of a supporting role as opposed to a leading role. We need enough for optimal hormonal production, tissue repair, cognitive function, and immune support but too much can pull us away from performance. With all things related to the body, the amounts are unique to each of us. One general metric we use at Big Dawgs when calculating fat intake for our athletes is the following:

To calculate rough fat intake for CrossFit Athletes:

BW x 0.4-0.6 = grams per day of fat

*In a general sense, closer to 0.4 for males and closer to 0.6 for females as they will need a bit more fat relative to a male. Take this as a general guideline as some might need more and some might need less. The athlete’s goal and functional demand of the sport will dictate what type of fueling is needed.

Let’s wrap it up. There are 3 different types of fats we want to consume in varying quantities (saturated, monounsaturated, polyunsaturated fatty acids). There are 2 types of polyunsaturated fatty acids we can’t create in the body and must consume via our diet, or through supplementation: Omega 3 and Omega 6 fatty acids. They work antagonistically with both serving vital roles for our health and performance. The building blocks of all our sex and corticosteroid hormones is cholesterol, an organic fat molecule. Our liver will produce roughly 80% of the daily amount of cholesterol we need while 20% will come from the foods we consume. The liver will tightly control this relationship and adjust production relative to consumption. If we are lacking in adequate amounts of fat, more specifically cholesterol, we can hinder hormonal production negatively impacting our ability to recover, grow, and perform. When looking at fat intake for performance, we have to see it as a supporting piece not the primary driver. For competitive Crossfit Athletes, daily fat intake will be on the lower end of the scale as majority of the fuel intake will need to come from carbohydrate sources (see my blog post on carbohydrate intake for more information). Don’t neglect fat intake, aim to choose from a variety of sources, and chew them well.


-Alan Aragon’s Research Review

-Precision Nutrition

-Food, Nutrition and Sports Performance II: The International Olympic Committee Consensus on Sports Nutrition

By: Ron Maughan,  L.M. Burke,  E.F. Coyle

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CrossFit® is a registered trademark of CrossFit, Inc. Big Dawgs' uses of the CROSSFIT® mark are not endorsed by nor approved by CrossFit, Inc., and Big Dawgs is in no way affiliated with nor endorsed by CrossFit, Inc.

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