Thursday, September 10, 2009

The Endurance Athletes Guide to Nutrition Part 2: Energy Sources

In Part 2 of this 6 part series I want to share with you some helpful information about energy sources that may help you adjust your diet to enhance your athletic endurance during training and racing.


If you know me, you know I like fat. Personally, I think Sisson said it best when he said "Animal fat makes everything better".

Awhile back I wrote an article called “Pass the Fat!” To quickly summarize:

• “Good fat” is good for you (olive oil, nuts, seeds, avocados, animal fat)
• Carbohydrates have their place in our diets, but not as much as you think
• We need to train our bodies to burn fat as a primary fuel source, which can be done through training and nutrition

Regardless of whether one is involved in endurance athletics or not, the bulk of calories consumed should be in form of good qualities fats. I am sure you are thinking that’s hard to swallow (no pun intended), but it’s the truth. I realize that this goes against everything you have been told, but bear with me and consider the following information.

When you are sitting at your desk, walking down the hallway to the printer, reading, this blog – or whatever it is that you do when you aren’t training (when you should really be training) - fat and protein are your primary fuel sources (ketosis). Your body and brain actually prefer these fuel sources since that’s what the body becomes accustomed to doing for the past 100,000 years. Since there aren’t a lot of energy demands on your system, your body has the time to break down fat and protein into forms of fuel. What you also may not know is that as a part of this process it also turns some of the fat and protein into glycogen (stored carbohydrate) for storage in your liver and muscles when you need it. Yes, you read that correctly - your body is able to create glycogen from fat and protein. It’s certainly a slower process than ingesting CHO, but it does happen.

Types of Fats – Essential Fatty Acids

They are termed “essential” because we can’t produce them ourselves, and that they are essential to our physical well being. Essential fatty acids are basically Omega-3’s and Omega-6’s. Evolutionary speaking, our ancestors typically consumed around a 1:4 Omega3-6 ratio. In modern times however, the western diet is disproportionately high in Omega-6’s because of the high amount of processed oils and grain-fed (as opposed to grass fed) meats we consume. Although they are essential, the imbalance of the 2 can cause havoc on us internally, mainly in the form of inflammation.

Omega-3’s come from healthy sources like fish, grass fed meats, avocado, fish, and certain types of nuts (e.g., macadamia, walnut). Ideally, you would strive for a 1:2-4 ratio of Omega-3/6. Some of the biggest benefits of Omega-3 are that:

• It is anti-inflammatory
• It is good for the immune system
• It helps with brain function (generally a good thing)

This is one of the few things that scientific studies agree on – that Omega-3’s are really good for you. Personally, I would argue that taking an Omega-3 fish oil supplement is one of the best things you could take.

Types of Fats – Monounsaturated, Polyunsaturated, Saturated and Trans Fats

Monounsaturated fat is generally considered a healthy fat and makes up about half of our cell membrane structure. Unfortunately, these fats can break down into free radicals – the very thing that endurance athletes have too much of, and the thing that anti-oxidants neutralize!

Polyunsaturated Fat is considered more “healthy” by the media (although I disagree). This fat can be very unstable during cooking thus forming free radicals – the very thing we are trying to get rid of with antioxidants (to be covered in Part 3)! It also has been proven to be immunosuppressive (i.e. detrimental to our immune system). It’s common for processed oils (safflower, corn, vegetable, soybean) to have high polyunsaturated fats, and high Omega-6’s. Coincidence? It’s also worth saying that with all the training that endurance athletes do, training actually weaken our immune systems (ever wonder why so many people get sick right before a race?), so these types of fats should be avoided.

Saturated Fat – I am going to open a can of worms here and say saturated fat can be GOOD for you (or at least not as bad as the media makes it out to be). I know you are thinking, “But I have always been told that fats, especially saturated fats, are bad for me!” To which I ask, “Who always told you? The US government?” Please refer to their food pyramid where they say fats should be used sparingly and Bread, Cereal, Rice & Pasta should be consumed 6-11 times a day! Then, look at the diet issues in our country. “

Although my rebuttal does hold merit, it doesn’t cover saturated fats being good. They are instrumental to hormonal balance. They are necessary to properly process and absorb vitamins. They enhance immune function and if you look at the membrane structure of a human cell, it’s 50% saturated fat!

Saturated fat doesn’t just come from animals either. There are plenty of healthy oils that are mostly saturated fat: palm kernel oil and coconut oil. Because coconut oil is a medium-chain fatty acid, it is immediately available to the body for energy. It requires little to no processing by your carnitine or lymphatic systems. Believe it or not, there are studies out there that show that higher intakes of saturated fat can actually prevent skin cancer.

Further, saturated fats are great cooking oils since they have much higher boiling temperatures, and don’t break down into cell damaging free radicals as easily, or under high heats as much as mono and polyunsaturated fats do.

Trans Fat – Regardless of how much of an aerobic base you have - just swim, bike or run away from these as fast and as far as possible!

Cholesterol - While reading this part on saturated fat, I am sure cholesterol has crossed your mind. Cholesterol is not a fat, but the American public tends to associate the two, so it’s worth touching upon.

Cholesterol is essential to life. In fact, it’s so essential that your liver produces it based on the body’s needs. Your body, being the evolutionary marvel that it is, is smart enough to know that if there is an increase in cholesterol through diet, and then the liver simply doesn’t produce as much. This is why vegans can survive without eating animal products, which are primarily the body’s only way of getting cholesterol from an outside source (even though plants do contain small amounts of it).

I don’t want to lose you with the explanation on why cholesterol gets a bad rap, but the layman’s version is eating a diet high in trans fats and CHO (especially simple sugars) will cause a number of issues, one of them being inflammation. Inflammation is now the widely accepted cause of heart disease, NOT cholesterol (as it was thought to be back in the 1950’s.). The problem is that cholesterol is guilty in the court of public opinion and that may not ever change. If people would really like me to, I could do a write up on saturated fat and cholesterol specifically, but that’s beyond the purpose of this article!


As for carbohydrates, let’s be clear: the main purpose of carbohydrates is to provide IMMEDIATE fuel for a strenuous physical task because they can be broken down so easily into fuel. What your body doesn’t use for immediate energy gets stored as fat, especially if consumed at night. This will be covered in Part 3.


Protein is found in nearly everything, but people typically associate protein and meat together - for good reason. Animal protein (including fish) is a complete protein in that it contains all, or nearly all, Branched Chain Amino Acids (BCAA’s). BCAA’s are really the building blocks for muscle regeneration, which helps our muscles recover faster (always a good thing for any type of athlete). Protein doesn’t really provide that much “energy.” A gram of protein contains 4 calories, and it takes your body almost 4 calories of energy to completely digest a gram of protein.

Animal protein should be your primary source of protein, but it doesn’t necessarily have to be meat. Whey protein can be a healthy substitute (especially for vegetarians), and one of the main benefits is that it can be absorbed into the body faster since it is in much more granular form, and is typically consumed as part of a liquid drink (e.g., shake, smoothie).

Ideally, if you can afford it, purchasing meat that is any combination of organic, grass fed, vegetarian fed, antibiotic & hormone free, free range is, simply put, best for you. These types of meats are typically a bit more expensive, but in my opinion, taste better, and are better for you. The grass fed types are typical leaner, and have higher omega-3 content since animals eat what they are supposed to eat – grass – rather than grains. This link helps describe the differences between them all. These types of meats are much more in line with what our ancestors ate.


• Healthy fats such as mono-unsaturated (Extra Virgin Olive Oil) and saturated fats (Butter, Coconut Oil) are good for you
• Polyunsaturated (ie. Industrial Processed Oils) and trans fat are bad for you
• Strongly consider taking an Omega-3 fish oil supplement
• Carbohydrates should be used primarily for immediate fuel and glycogen replenishment
• Clean animal protein is best for recovery and well being


Toby Guillette said...

I eat lots of pastas and whole grains in my diet because I thought that's what I was supposed to be doing to keep my energy levels going. I'm absorbing as much of this as I can right now. Thanks again for sharing the knowledge and helping me restructure my approach to endurance nutrition.

Chuckie V said...

Keep this series going Denner. I shall be linking to it in the future, I'm sure.

On a side note regarding this subject, the thing I find utterly amazing with the elites I guide is how many of them can make every necessary sacrifice. Until it comes to the kitchen, that is!

They're willing to train really, really hard. They will also nap, stretch, lift, pay for massage, read what I ask them to, etc. But when I advise them to limit the late night snacking or their caffeine intake or work on eating more REAL food, they tend to drop the ball. What is it about nutrition that makes it so hard on us? Are our taste buds really in that much control? Are we that weak?


Ryan Denner said...


I'd be curious to hear if this is an issue with US-based elites specifically, or elites around the globe. I wouldn't be surprised if it's primarily US based, given the culinary environment we have surrounded by a bunch of processed foods such as breads and pastas. Not to mention the never ending marketing of bars/gels that athletes think they *need*.

What's funny, is I am sure if you ask a professional race car driver what they put in their car, I am sure its the best quality fuel they can get their paws on. Same concept, different application. Go figure.