FAT a burning question for the long distance runner


Racing in any running race requires a specific and targeted approach to your objective. The objective can be a one day race of a short distance, a medium distance race such as a marathon or maybe you are going to run long, 50 miles or more… You may even be running for multiple days?

The important thing to remember is that ‘training’ and ‘racing’ are 2 separate things and your fuelling approach should reflect this.

Any long distance event will require you (a unique individual) to utilise fat as a fuel source. You can teach your body to utilise a greater amount of fat as fuel and also to use less calories overall, making you more economical.

Other factors come into play, for example, someone who will be in the top 5% of the race results will have different needs to a runner in the final 5%. However, fat as a fuel is used and we can all adapt.

If you follow the guidance below over a 12-16 week training period you will adapt to fat usage.

Run at the correct intensity -slow and steady. Find out a specific heart rate zone in which to work. Maffetone method is a good starting place.

Avoid fluctuations in intensity when training long, average heart rate or power output are NOT the critical figures, it’s TIME IN ZONE that counts.

Eat foods which are balanced with low GI (glycemic index) carbohydrates and fats to encourage fat usage and avoid sugar spikes.

Avoid gels and sugar products based on point 3 above.

What happens during the race?

Let’s assume that while racing you burn 700kcal per hour, 50% of which comes from carbohydrate and 50% of which comes from fat. Carbohydrate loss is the one to worry about, in this scenario, 350cals (50% of 700). 350kcal of carbohydrate equates to 88 grams of carbohydrate (4 kcal per gram).

Here’s the big problem!

Most individuals can only absorb approximately 60g+/- of carbohydrate per hour.

A simple way to look at this is by looking at ‘you’ as a car ferry. The cars that you will fit in the ferry boat carry carbohydrate, lets say 10g per car. Your car ferry only holds so many cars… in our scenario it is 6!

But we have already worked out that you as an individual burning 50/50 carb and fat require 88g of carb. That is 8.8 cars.

So, you line up 9 cars on the dock every hour but only 6 fit. This leaves 3 on the dock. The boat sails away, comes back 1-hour later and 9 new cars have arrived in addition to the 3 you left waiting…

This is the same as adding carbs through your intestine wall to your blood stream. If you carry on missing 2.8 cars every hour, one thing is guaranteed to happen – you will either need to slow down or you will blow up!

As stated, a typical person can absorb 60gram +/- per hour.

For our example above, that means that you’re going to fall short. You’re using 88 grams per hour and you can only replace 60 grams per hour. That’s a 28 gram / 112 kcal per hour deficit.

If you try to eat more (an additional 2.8 cars) every hour, it’s unlikely to be digested and will simply sit in your stomach or intestines without providing energy. That may be okay for 1-hour, possibly 2 but then the classic scenario of stomach distress happens. How many runners have you talked to that have complained of stomach distress while running?

It’s really important that you understand, eating more food doesn’t mean you’ll have more energy and it may well mean that you’ll face stomach upsets.

Our above scenario works on the presumption that you are only using 700kcal per hour, bigger people and less efficient people may be using more? Our scenario also assumes that 50% is coming from fat and 50% fro carb – that may not be the case at all! In-fact, as much as 80-100% of energy may be coming from carbohydrate! A disaster for the endurance athlete.

Take multi-day racing for example when you are racing day-after-day with compromised recovery and limited calories. You just simply cannot carry enough carbohydrates to sustain you over the period of an event, particularly if it is a self-sufficient event such as the Marathon des Sables.

To move forward effectively armed with good knowledge about you as a person, you need to address 3 questions:

How many calories do I burn per hour?

How many of those calories come from fat and carbohydrate?

How many calories and what percentage of fat/ carb should I be taking in as a consequence?

Do a 1 hour run at your ‘race pace’ and then use your heart rate monitor to calculate how many calories per hour you are using when exercising at that intensity. These figures can be somewhat unpredictable but it will provide a starting point from which to work from.

Most heart rate monitors will use your age and weight to work out kcal per hour. This will only give you an approximate calorie burn per hour and won’t tell you what % of energy comes from carb/ fat. There are some tools on the internet such as: http://www.braydenwm.com/calburn.htm which can help to give you a basic idea.

Working scenario:

Billy is 43, weighs 82 kg and is racing a 100 mile race, he falls into a category of 65 carb /35 fat fuel usage. Billy has one main objective – to complete the event without major disaster and to run as much as possible. Billy running at his proposed race pace will use 820 Kcal per hour, so the calculation works like this:


Fat contribution:  820 Kcal x 35% = 287 Kcal

Carbohydrate contribution: 820 Kcal x 65% = 533 Kcal

Calories from fat do not need to be replaced – we all have plenty of stores. However, carbohydrate NEEDS replenishing and the body can only hold so much. 1g of carb is 4kcal. So, Billy will require 133g per hour!

Uh oh! We have already clearly said that around 60g of carb per hour is all that we can take. Billy is in trouble… he is missing out on 73g per hour. Remember the car ferry and the cars sitting on the dock waiting to get on the boat – Billy, racing over 100-miles will need a multi-story car park for the cars that won’t fit on his boat.

Although Billy is a ’sample’ case, this scenario happens time and time again in races all over the world.

How do you solve this problem?

Billy needs to utilise fat as a fuel more and be less reliant on carb.

The body is pretty clever. It is able to switch its metabolism. So, in the case of Billy, the availability of carbohydrate is becoming an issue, as a result the body will start to utilise fat stores. This is a good thing. Yes? Well yes but one thing will have to happen – Billy will need to slow down. Now for many of us, that is not an issue as a finish is a primary goal. However, this can be hard to take and yes, you may well feel lousy. More importantly, pre-race objectives may go out of the window… target times will be lost and a possible top-10 (if that was an objective) will also go out of the window.

Let’s cut to the chase

If more of your energy comes from fat, you’re less likely to run out of carbohydrate. The best athletes in the world require energy (Kcal) to run at race speed. If a large chunk of that energy requirement comes from fat, their total carbohydrate use is reduced.

As an example, by making changes to Billy’s training and diet, the new version arrives for the 100-mile race using only 700Kcal per hour and 55% of energy is being provided by fat.

A quick maths calculation reveals the following:

1. He’s using 315 Kcal of carbohydrate per hour on the run, compared to the previous figure of 533

2. With his intake of 60 grams per hour (240 Kcal), he now only has a deficit of 75 Kcal per hour compared previously with 292 Kcal (73 grams)

3. As a consequence, Billy could run the whole 100-mile race with a smile.

In conclusion:

For you to run an ultra feeling comfortable, relaxed, efficient and on target, you need to go away and find out:

How many calories do you burn per hour?

How many of those calories come from fat and carbohydrate?

How many calories and what percentage of fat/ carb should I be taking in as a consequence?

You may well find that you need some specific help in working out some of the data and figures outlined above.

A Metabolic Rate Test HERE and a Metabolic Test is the way forward HERE.

In training (not all training, just the slow/ steady runs):

To recap earlier points:

Run at the correct intensity – slow and steady. Find out a specific heart rate zone in which to work. Maffetone method is a good starting place.

Avoid fluctuations in intensity, average heart rate or power output are NOT the critical figures, it’s TIME IN ZONE that counts.

Eat foods which are balanced with low GI (glycymic index) carbohydrates and fats to encourage fat usage and avoid sugar spikes.

Avoid gels and sugar products.

Finally, daily diet plays a key role in overall adaptation. Simple sugars, processed food and so on are all bad in day-to-day life for an endurance athlete. Keep them at a minimum and as a treat.

Periodise your eating just as you would training.

Think about dietary fat and fat-burning and think low carb.

A low carb and high fat (LCHF) diet forces ones body to burn fat. As you will now know, fat stores are pretty much unlimited even in the skinniest guy or girl. Optimising ones body to use fat will use less carbs and allow you to perform longer. This becomes even more relevant in long endurance events, especially when the pace is slower and the energy requirement to run at a certain pace is lower.

Notice I say low carb and not no carb! Carb has a place in your diet, it just needs to be consumed at the correct times and make sure the carbs you eat are low GI and good quality. Avoid white pasta, white bread, anything refined and potatoes for example (high GI) and eat sweet potato, beans, whole grains (but be careful) and plenty of vegetables (low GI).

Protein is also key for recovery, muscle growth and repair.

A typical runners diet, broken down into percentages of fat, protein and carb would have often (and in many cases still does) look like this:

Carb 60%

Protein 15%

Fat 25%

The modern day ultra, endurance or multistage runner has percentages that look like this:

Fat 50%

Protein 30%

Carb 20%

Of course, we have all been told that high fat is bad for us but sugar and in particular, refined sugar is the real evil and in day-to-day life it just doesn’t help you as an ultra runner.

Note though, fat should be good quality – oily fish, nuts, seeds, good quality meat, olive oil and so on. Bad fats are the obvious ones such as crisps etc.

Periodise your food intake

Just like you will plan training – intervals, hills, long runs and so on. Food should also be planned in-line with training and racing needs. I will write more on this in another post.

In simple terms:

Train fasted for long runs and keep your pace low to promote fat burning. Actually eating fat before a long run has benefits in helping and promoting fat burn. As does coffee. Try Bulletproof coffee before long and slow runs, read here

Recovery consume a little good quality carbohydrate post training, ideally within a window of 30 to 40-minutes and include good quality lean proteins.


When racing a long distance race, you as a runner will be far more efficient at using the calories that you have within your body if you follow the guidelines above. We have already said that the body can only hold so much carbohydrate, so, if you have your fat burning turned on you will go longer. Your food requirements whilst racing will also change and you will require less sugary products to keep you going.

Pace (the speed you run) will also impact on how the carb/ fat ratio is used. Runners who are racing (looking for a top placing) incorporate different methods to perform. Often called, ‘train low and race high’ – Timothy Olson for example is a good example. Timothy eats high-fat and low carb in training and day-to-day life but when he races he uses sugar (such as gels) to fuel him during the run. His training has adapted him to use less gels (he uses more fat as fuel), last longer and each sugar smack he gets while racing has less work to do as his carb stores are always being used in conjunction with fat.

Carb loading has been used for years and it’s often misunderstood. How many times have you seen or heard a runner gorging on carb for days before a race – why? We already know that our body can hold so much stored carb (approx 2500 cal) so, when we ‘carb load’ we are basically making sure that our carb stores are full pre a race. Don’t over indulge. It will just sit in your stomach, cause discomfort and make you feel lethargic and more than likely, you will add weight to your frame. As a guide in the 24-hour period before your race, keep a balanced diet but up the carb % say from 20 to 35/40%. Again, make this good carb – low GI.

What is key here is finding what works for you.

“The benefits of low carbs really start to distinguish themselves when you get beyond the marathon, because you’re definitely running out of carbs then,” – Jeff Volek


Always check with a medical professional before making any drastic change to your eating  or training regime. The information provided in this post is designed to make you question and pursue an opportunity to enhance your training and racing and we stress that you must find out what personally works for you.

Thanks to Marc Laithwaite for his contribution to this post.

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Timothy Olson – Low Carb

Earlier this summer, Steve Phinney and Jeff Volek, authors of The Art and Science of Low Carbohydrate Performance, headed to the Western States 100-mile Endurance Run, to study how runners in this grueling race fared, literally, for they were checking how the athletes performed AND how they ate.

Steve Phinney says that more and more endurance athletes are choosing low-carb, high-fat.  They’re choosing this diet both to get over digestive problems that hit in such a demanding event, and to win the race, and win it BIG!

That’s what Tim Olson did this year.  A self-proclaimed low-carb eater, Tim won the race — with a record-breaking pace.

You may like to read the article HERE

This obviously links into my previous post on the 40-30-30 diet

Timothy Olson

40-30-30 Diet

40-30-30 means eating the right balance of carbohydrates, protein, and fat. When you eat a 40-30-30 meal, 40% of the calories in that meal are from carbs, 30% from protein, and 30% from fat.

When you get the right amount of carbs, along with the right amount of protein and good fats, your body naturally burns fat. And, you aren’t hungry between meals. Plus, you feel better – your mind is clearer and you have more energy. For endurance athletes this ability to utilize fat as a fuel source is something we all need. The old adage of carbo loading’and consuming vast quantities of carbohydrate is slowly but surely being tipped on its head with the smart athlete now consuming considerably less carbs in preference for a more ‘balanced’ diet and one that uses the GI scale to help consume proper calories to maximize performance.

You can listen to a podcast on the 40-30-30 diet with Ian Corless from Talk Ultra and Marc Laithwaite HERE


40-30-30 is a specific nutritional balance of 40 percent calories from carbohydrates, 30 percent from proteins, and the remaining 30 percent from fat.

Dr. Barry Sears originally created The Zone Diet for cardiologists, to teach them to use food as if it were a drug. He advocated diet as treatment for heart disease and diabetes. Those two diseases are also tied to excess production of the hormone insulin, the underlying hormonal disturbance that also causes obesity.

Patients on the program quickly reported that eating balanced meals made them feel better. Most of them also noticed that they were losing weight. When you eat a nutritionally balanced diet, your body naturally adjusts to keep you healthy – including dropping those extra pounds you don’t need.


It’s adjusting the amount of three key macronutrients you eat to keep your body in hormonal balance. The ideal is to:

  • Provide enough low glycemic carbohydrates to feed your brain and keep you sharp mentally, without spiking your blood sugar and triggering an insulin response.
  • Provide enough protein to maintain muscle mass, and to trigger fat burning through release of the hormone glucagon.

Provide enough fat that the body can absorb fat-soluble vitamins – A, D, E, and K, and Linoleic acid (necessary for growth and reproduction).

GI – Glycemic Index

The Glycemic Index (GI) is the measure of the amount and the rate of an increase in blood sugar after eating a carbohydrate. The higher the GI, the larger the rise in blood sugar, and the more insulin is released. Unfortunately the more insulin in your system, the more fat you’ll retain.

Eating 40-30-30 reduces your glycemic load. High glycemic foods (like candy bars) will give you fast, abundant energy, which unfortunately fades quickly, and is replaced by sleepiness. But when you eat low glycemic carbohydrates like an apple, an orange, pear, or strawberries, you are less hungry between meals and more mentally clear. You feel great, you lose fat, you have more energy, and your mood will be stable.

A low glycemic diet is not a low calorie diet. It is possible to eat fewer calories and not be hungry.

Nutritional Standards

Glycemic Index is based on a scale of 0 to 150.

  • Low is within the range of 0-35,
  • Medium is 36-70,
  • High is 71-100,
  • and Very High is over 100.
  • The Glycemic index cannot be calculated, only measured in lab testing on humans

Learning about GI can be very interesting and certainly you may be very surprised by some of the results that you find

Here is a very useful tool. You can input your food choice and find out its index. Click HERE

  • To search for a food, enter the name only.
  • To generate a list of all high GI foods, enter > 55 in the glycemic index field.
  • For a list of low GI foods, enter < 55 in the glycemic index field.
  • If you enter bread in the name field and < 55 in the glycemic index field, you’ll get a list of all breads with a GI less than 55.
  • Foods containing little or no carbohydrate (such as meat, fish, eggs, avocado, wine, beer, spirits, most vegetables) cannot have a GI value.
  • No carbs = no GI.

Putting it into practice

Adopting a 40-30-30 diet is not difficult. You can view a guide to GI tables here. In principal you want to maintain the balance of 40-30-30 and when eating carbohydrate ensure that it is low GI. When eating breads, pasta and rice ensure they are brown or whole-wheat. Eat good lean proteins and ensure that your fats are good fats such as those that come from oily fish, olive oil and nuts.

In simple terms, the 40-30-30 diet involves cutting out most carbohydrates such as breakfast cereals, rice, potatoes, pasta, noodles, bread, bagels, croissants, muffins, crisps, pastries, pies, chocolate, sweets, sugar and preserves, as these have the greatest effect on blood sugar levels and therefore insulin levels.

Most fruit and vegetables, however, are allowed. Low-fat protein-rich foods such as skinless chicken, turkey and fish should be eaten with every meal. Meanwhile, eating fewer foods that contain saturates and choosing foods that are rich in monounsaturates, such as olive oil, avocado and nuts, is recommended.

Divide your plate into three equal sized sections and then filling one section with low-fat protein such as chicken – making sure it’s no larger or thicker than the palm of your hand – and the remaining two sections with vegetables and fruit. Adding a little olive oil, avocado or a few nuts will help to boost intakes of monounsaturates!

Of course as an athlete you need to think about your food choices in relation to your exercise and racing. For example, reducing carbohydrate intake and eating fats before long training sessions or races will teach your body to utilize the fats that are within your body and use them as fuel. Initially you may feel a little unusual and crave carbohydrate but after 2-3 weeks you will adapt well. During exercise and racing you will need to refuel, particularly for longer races but think about the pace you are running/ cycling at and the energy requirements your body needs. Gels are not always the answer but if you hit a low spot or if you feel flat a gel may be just what you need to ‘lift you up’.

The important thing is that we are all individual. You need to play around with your diet and find out what works for you.

RECIPES linked to iwantfreehealthyrecipes.com

Aragula Scramble: This is a quick breakfast, but because you don’t see arugula used much, it seems kind of elegant.

3 eggs
1 cup arugula

1/2 tomato, diced
1 tbsp Parmesan cheese
2/3 cup dry quick oats
1 1/3 cup water
1 cup skim milk

First, get your oatmeal & water cooking in the microwave. Chop the arugula & tomato roughly. Scramble the eggs. Spray a nonstick frying pan with Pam and preheat to medium. Stir-fry the arugula just until wilted, maybe about a minute, then toss in your eggs. Stir over medium heat until almost cooked, and stir in your tomato for the final minute or two. Top with about a tablespoon of grated Parmesan cheese. Serve alongside the oatmeal and milk.

48 g carbs (39%)
36 g protein (29%)
20 g fat (32%)

Popeye Fritta: A fritatta like this is a great make-ahead breakfast. Put it together while your making dinner the night before, and you can just pop a slice into the microwave in the morning, and get rolling out the door!

4 eggs
3/4 cup cooked chopped spinach (1 pkg. of frozen spinach)
1/4 cup chopped fresh parsley or cilantro
1/4 cup chopped tomato1/4 tsp. sea salt
1/2 tsp. chopped garlic
1 tbs. margarine
4 chopped green onions
1 tbs. chopped hazelnuts, walnuts or sesame seeds

Beat eggs. Combine with spinach (make sure it’s well squeezed first!), parsley or cilantro, garlic and sea salt. Saute the green onions in a medium oven proof frying pan, using the margarine. When the onions are slightly wilted, add the egg mix. Cook over a high heat until the egg starts to set up, shaking constantly to prevent burning. Finish under a broiler for several minutes. Top with the chopped nuts. Makes 2 servings.

Santa Fe Chicken Soup: This is one of our family’s favorites. We eat it all the time in the winter. Even our normally picky kids love it.

1 1/2 lb. chicken breasts
2 large green peppers

2 cups onion
2 cups carrots
1 cup tomatoes
1 1/2 cups corn kernels
1/2 cup green chiles
1 qt. water
1/3 cup chicken broth
1 1/2 cups wheat flour
5 tbs. butter
6 cups milk
2 tbs. garlic powder
1 tsp. white pepper
1 tsp. black pepper
1 tbs. cumin
1 tbs. Cajun spices
1 tsp. cayenne pepper
1 tbs. seasoned salt
2 tbs. onion powder
5 tbs. chili powder

Start by broiling the chicken. When cooked, shred or dice it, and place in a large stock pot. Dice the peppers, onions, carrots and tomatoes.

Note, we normally add the chopped veggies to the pot now. But if you’ve got picky eaters at home, you could always give these a quick shot in the blender first. It’ll grind them up so they’re unrecognizable, but they still give the soup a ton of flavor, and some added thickness as well.

Add in all remaining ingredients except for the butter, flour and milk. Bring to a boil, then let it simmer on a low burner.

In a medium saucepan, melt the butter. In another saucepan, heat the milk until steaming, then remove from the burner. When the butter is melted, slowly whisk in the flour. Avoid lumps. As the mixture becomes too dry to work with, slowly alternate adding the flour and the milk. When you’ve combined all of the butter, flour and milk, whisk this mixture slowly into the simmering soup. Let the whole thing cook on low for another 20 minutes.

Makes 10 servings. It will keep in the refrigerator for about a week, and freezes well.

Almond & Chicken Casserole: 2 lb. cooked chicken meat (light and dark)
2 lb. red potatoes
4 stalks celery
1 medium onion

4 cloves garlic
2 cans cream of chicken soup (Healthy Choice or other reduced fat)
1/2 cup slivered almonds
1/2 cup chicken broth
1/4 cup lemon juice
1/2 tsp. salt
1/4 tsp. pepper
2 tbs. olive oil
3/4 cup bread crumbs

Shred the chicken. Chop the potatoes into bite-sized pieces, and steam or boil until about half cooked. Dice the celery & onion, and peel and chop the garlic finely. Mix all of that in a big bowl with the almonds, soup, broth, juice, salt and pepper. Stir it all well, and pour into a greased 13 inch X 9 inch pan. Mix the oil and bread crumbs thoroughly, and sprinkle on top. Bake at 350 for about 30 minutes. Serves 8

Chille Casserole: 12 whole green chille’s
4 oz shredded jack cheese
4 eggs
1/3 cup milk
1/2 cup whole wheat flour
1/2 tsp baking powder
1 cup (4 oz) shredded, sharp cheddar cheese

Split each chille the long way. Remove the white pith and seeds. Stuff the chilles with the Jack cheese, wrapping each chile tightly around the cheese. Spray a 1 1/2 quart baking dish with nonstick spray, and arrange the chiles in one layer in the pan.

With an electric mixer, beat the eggs on medium-high until thick and foamy. Add the milk, flour and baking powder, and beat until smooth. Pour the egg batter evenly over the chiles. Sprinkle the top with the shredded cheddar cheese.

Bake the chiles uncovered at 375 until the dish is somewhat puffed up (about 1/2 hour). Makes 6 side dish servings.

NOTE: I included this recipe because it’s a great dish, and in terms of carbs vs. protein, the proportions are right on. On the other hand, I’m sure you noticed it has a HUGE fat content. So unless you’ve had a really bad day, combine a small portion of it with a lowfat burrito.

Chicken & Pineapple Stir Fry: 1 lb. boneless chicken breasts
1 lb. broccoli tops
1 medium red pepper
1/2 cup chopped green onions
8 oz. can pineapple chunks
1 tsp. chopped fresh ginger
2 tsp. cumin
1 clove garlic
2 tbs. soy sauce
2 tbs. corn starch
1 tbs. sesame oil
2 tbs. pineapple juice.

3 cups cooked brown rice

Cut the chicken breasts and broccoli into bite-sized pieces. Slice the pepper into thin strips, and chop the green onions. Crush the garlic, and chop the ginger finely. Heat the sesame oil in a nonstick skillet on high heat. Stir fry the chicken and broccoli. Add the ginger, cumin, garlic , pepper and green onions. Cook for about 5 min. While that’s cooking, drain the pineapple chunks and add about 2 tbs. of the juice to the cornstarch. When the stir-fry mixture is cooked, add the pineapple, soy sauce and cornstarch mixture. Continue cooking briefly until the sauce thickens, and serve immediately over brown rice. Makes 6 servings.

More menus are available here: linked to iwantfreehealthyrecipes.com