Tag Archives: athlete

Burn Fat for Fuel | The Paleo Diet

The marathon and triathlon seasons are fully underway and this year over half a million people will complete the marathon and thousands more participate in triathlons and other endurance events. Whether they’re entering an event for the first time or trying to achieve a personal best time, one of the most common questions I get asked by clients is “what should I eat before my long run?” The answer may surprise you!

A common refrain amongst most endurance coaches is that you must consume a heavy carbohydrate meal before your long run or bike to perform your best. High carbohydrate breakfasts of oatmeal, cereals, and juice or the classic ‘carb-load’ pasta dinner are staple recommendations from many top endurance coaches. While this is certainly not bad advice, there is another option.

Don’t eat any carbs before your long run or ride! (Yes, you heard me correctly.)

Let’s take a moment for a quick physiology review. When carbohydrates are ingested they are preferentially burned for fuel and provide 4 calories per gram of energy. When fats are ingested, or burned from body stores, they provide 9 calories per gram of fuel. You are effectively doubling your fuel efficiency if you use fat are your primary fuel source from the outset.

By maximizing your capacity to burn fat for fuel, you’ll also be sparing precious muscle glycogen, the carbohydrate stores in your muscle. You have approximately 500g of glycogen stored primarily in your muscles (and some in your liver) that can provide you with 2,000 calories of energy during your race. In contrast, even lean individuals between 7-14% body-fat have 20,000-30,000 calories available for energy use in their fat stores. Wow! That’s a lot of fuel that could be used, if you changed your pre-race food choices.

Skeptical? I don’t blame you, but the preliminary results are impressive.

Dr. Jeff Volek PhD is a world-renowned researcher and author of the FASTER (Fat-Adapated Substrate oxidation in Trained-Elite-Runners) study due to be released later this year. Dr. Volek and his team are investigating the impact of very low-carb diets on an athlete’s capacity to burn fat for fuel, compared to the traditional high-carb diets used by endurance athletes.

A traditional high carb diet would be broken down to approximately 60% carbs, 15% protein, and 25% fat. A low-carb diet would dramatically increase the fat intake to 70%, provide slightly more protein at 20%, and carbs would only make up 10% of the total daily energetic intake.

The initial data is sending shockwaves through the exercise community. Why?

It has been well established in the scientific literature for years that the maximum amount of body-fat that can be burned per minute is 1.0 grams, while the average athlete burns between 0.45-0.75g per minute. 1

The initial results from Dr Volek’s FASTER study smash this concept, showing the LCD athletes are burning upwards of 1.1-1.8g/minute which is way beyond what was thought physiologically possible. 2 You can see the peak fat oxidation or burning rates in the graph below.

Peak Fat Burning During VO2 Max

Traditionally, it was believed that somewhere between 35-65% of your maximum heart rate you switch from burning fat for fuel to carbohydrates. 3 However, this new research is re-shaping the way we think about fueling endurance athletes. The graph below highlights the body’s capacity to burn fat on a low-carb diet at much higher training intensities than thought possible. 2

Fat Oxidation Versus Exercise Intensity

If you ingest primarily carbohydrates your body quickly shifts over to burning the ingested carbs, and your body’s glycogen stores, for fuel. However, if you eat primarily fats and protein before exercise you’ll be able to tap into your fat reserves more effectively. This allows you to spare your muscle glycogen for further along in the race, when you really need it!

This new research is in-line with an ancestral or Paleo approach to eating. You don’t need to rely on an endless array of gels, powders, and pills to produce the best possible endurance race times. If you are engaging in endurance sports to lose weight this is critical, as your excess carbohydrate consumption is likely holding you back from achieving a better body and better health.

For example, you could start your day with a coffee and a tablespoon or two of coconut oil or MCT oil. The caffeine helps stimulate lipolysis, the breakdown of body-fat stores to free fatty acids for fuel and the MCTs provide the added instant energy source. Alternatively, you could have eggs with avocado and a serving a stir-fried kale or spinach. This will allow your body to burn fat for fuel more effectively, as well as improving your health.

Not everyone needs to follow a low-carb diet. If you are purely performance-based and striving for new personal bests than you may want to tread lightly. (Check out my previous article on Eating Enough Carbs Optimal Recovery to get your post-exercise carb fix). However, in a sport like endurance training where carbohydrates are king, this compelling new research highlights that we still have a ways to go in understanding how to most effectively fuel the body for endurance performance.

Train your body to burn more fat and watch your performance, as well as your health, reap the benefits!



1. Venables et.al.; “Determinants of fat oxidation during exercise in healthy men and women: a cross-sectional study”. J Appl Physiol (1985) 2005 Jan;98(1):160-7.

2. Defty, President VESPA, Peter. “The Emerging Science on Fat Adaptation | Ultrarunning Magazine.” Ultrarunning Magazine The Emerging Science on Fat Adaptation Comments. Ultrarunning Magazine, 16 Dec. 2014. Web. 1 May 2015.

3. Lima-Silva A et al. Relationship between training status and maximal fat oxidation rate. J Sports Sci Med. 2010 Mar 1:9(1):31-5

4. Noakes, T., J.S. Volek, and S.D. Phinney. Low-carbohydrate diets for athletes: what evidence? British Journal of Sports Medicine. 48(14):1077-8, 2014.

Be More Human | The Paleo Diet

Congratulations to the winner of the Reebok #BeMoreHuman Sweepstakes, David! Thanks for sharing your story!

“Started last year at 275 lbs. Implemented a Paleo lifestyle, working out, hiking and adding fitness bootcamps this year, have lost 80lbs and feeling the best I have in 20 years. I sleep better, have more energy, and find my passion for great healthy food and an active lifestyle life changing. Every week I am doing some great new hike, bike ride, and learning more about fitness and health everywhere I can. What is a better representation of being more human than living life, a healthy life?!”


Mary Maginnis | The Paleo Diet

2014 Royal Canadian Henley Regatta Championship Women’s Single Champion

Dear Professor Cordain,

My name is Mary Maginnis, I am a Paleo athlete training for the Olympics, and I am writing to thank you for your work, The Paleo Diet for Athletes.

To offer you some background: I began rowing in high school and continued my career on the Division I level at Harvard. Although I was always on the shorter and leaner side for a rower, I spent these first eight years of my rowing career competing as a heavyweight. I was lucky that I was able to find as much success in that weight category considering my size, but I knew that if I wanted to continue rowing on the elite level, I would have to make the switch to lightweight.

To be clear, I spent most of my rowing career eating as anti-paleo as possible. I abhorred most vegetables, and I viewed pizza and cheeseburgers as the best-tasting foods (and I admit that I still think that they–retrospectively–taste awesome).

While I considered training full-time after college, I was instead initially drawn to a corporate position in New York City. I certainly gained a lot from this experience, but I knew after the first six months of work that I was giving up my only opportunity to achieve my long-standing Olympic dream. Corporate life will always be there for me, but competing in the Olympics is only achievable for a limited period of time. I left New York in the beginning of March and began training full-time as a lightweight in Philadelphia with a high performance group.

The switch to lightweight necessitated a change in how I viewed food. It made me especially conscious of how and when I was fueling my body. At this point, I had already been on the Paleo Diet for almost a year; my mother and brother had been Paleo for some time and inspired that change in my eating. “Being Paleo” not only made losing weight much easier in the transition from heavyweight to lightweight, but it also positively affected my energy levels and my performance. I noticed that I felt better most of the time while I was training compared to how I had felt throughout high school and college. I knew that the Paleo Diet was positively affecting my speed, and I became eager to learn more about how diet can affect athletic performance.

After doing some research online, I came across The Paleo Diet for Athletes and picked up a copy from a local Barnes and Noble. Since reading it, I have been able to make the Paleo Diet work to my athletic advantage even more. Understanding, specifically, what my body needs and when, has had an incredible impact on my training and performance.

In what has been only my first season competing as a lightweight and on the elite level, I have, to the surprise of many, managed to put myself in contention for this year’s national team. I am beginning to see my Olympic dream as more of a potential reality, and I certainly have you to thank in part for that. When asked what the “secret” to my speed is, my response always includes a recommendation to read your work.

Reading your work and implementing it in my own life has also inspired a passion in me for the cross between food and fitness. Too many of my fellow elite rowers take food for granted as fuel. I firmly believe that diet can be what I like to call “free speed,” and I am interested in learning more and inspiring others to make this change in perspective. As I train for the Olympics, I am hoping to involve myself in this in some capacity professionally and/or academically, whether that be through research, study, or otherwise.

Again, I cannot emphasize enough how significantly your work has influenced my life. Thank you for giving me a competitive edge, and thank you for helping put me on the track to achieving my goals.

Kind regards,

Mary Maginnis
Elite Rower Champion



I ran the ACU (Association of Canadian Ultramarathoners) 100Km National Championship. I lead the race the entire time, finished in 08:47:18 hours,and won by 23 minutes! I ran this race with a total of 850 calories of a fat/carb/protein blend, finishing the race as strong as starting it.

Endurance Athlete | Adam Takacs

Adam Takacs, 1st Place ACU 100Km Championship

In the past, I would need about 1400-1600cal of sugar to keep going strong and most likely fading towards the end, similar to many other endurance athletes.

As an endurance athlete, the adoption of eating/living a Paleo lifestyle made complete sense to me after some research. After some trial-and-error with my macros, I opted for a higher fat content- lots of bacon!- for more sustained energy. Injuries seem to have vanished, mid-day energy lows are gone, I never feel hungry, and after a win at the Pick your Poison 50KM run and a win at the National 100Km Championship in Niagara, I have no doubts I’ve found my secret weapon.

Adam Takacs

Modern Workouts | The Paleo Diet

Very few modern people have ever experienced what it is like to “run with the hunt.” One of the notable exceptions is Kim Hill, Ph.D., an anthropologist at Arizona State University who has spent the last 30 years living with and studying the Ache hunter-gatherers of Paraguay and the Hiwi foragers of southwestern Venezuela. His description of the amazing hunts which follow represents a rare glimpse into the activity patterns that would have been required of us all, were it not for the Agricultural Revolution.

Kim shared his story with me about a decade ago, which should be read by all contemporary athletic trainers, CrossFit enthusiasts and by The Paleo Manifesto‘s John Durant and Breaking Muscle’s Erwan Le Corre, both good friends and colleagues who espouse ancient activity patterns for modern humans living in the western world.

“I have only spent a long time hunting with two groups, the Ache and the Hiwi. They were very different. The Ache hunted every day of the year if it didn’t rain. Recent GPS data I collected with them suggests that about 10 km per day is probably closer to their average distance covered during search. They might cover another 1–2 km per day in very rapid pursuit. Sometimes pursuits can be extremely strenuous and last more than an hour. Ache hunters often take an easy day after any particularly difficult day, and rainfall forces them to take a day or two a week with only an hour or two of exercise. Basically they do moderate days most of the time, and sometimes really hard days usually followed by a very easy day. The difficulty of the terrain is really what killed me (ducking under low branches and vines about once every 20 seconds all day long, and climbing over fallen trees, moving through tangled thorns, etc.). I was often drenched in sweat within an hour of leaving camp, and usually didn’t return for 7–9 hours with not more than 30 minutes rest during the day. The Ache seemed to have an easier time because they “walk better” in the forest than me (meaning the vines and branches don’t bother them as much). The really hard days when they literally ran me into the ground were long distance pursuits of peccary herds when the Ache hunters move at a fast trot through thick forest for about 2 hours before they catch up with the herd None of our other grad students could ever keep up with these hunts, and I only kept up because I was in very good shape back in the 1980s when I did this.

The Hiwi on the other hand only hunted about 2–3 days a week and often told me they wouldn’t go out on a particular day because they were “tired.” They would stay home and work on tools, etc. Their travel was not as strenuous as among the Ache (they often canoed to the hunt site), and their pursuits were usually shorter. But the Hiwi sometimes did amazing long distance walks that would have really hurt the Ache. They would walk to visit another village maybe 80–100 km away and then stay for only an hour or two before returning. This often included walking all night long as well as during the day. When I hunted with Machiguenga, Yora, Yanomamo Indians in the 1980s, my focal man days were much much easier than with the Ache. And virtually all these groups take an easy day after a particularly difficult one.

By the way, the Ache do converse and even sing during some of their search, but long distance peccary pursuits are too difficult for any talking. Basically men talk to each other until the speed gets up around 3km/hour which is a very tough pace in thick jungle. Normal search is more like about 1.5 km/hour, a pretty leisurely pace. Monkey hunts can also be very strenuous because they consist of bursts of sprints every 20–30 seconds (as the monkeys are flushed and flee to new cover), over a period of an hour or two without a rest. This feels a lot like doing a very long session of wind sprints.

Both my graduate student Rob Walker and Richard Bribiescas of Harvard were very impressed by Ache performance on the step test. Many of the guys in their mid 30s to mid 50s showed great aerobic conditioning compared to Americans of that age. (V02 max/kg body weight is very good.) While hunter-gatherers are generally in good physical condition if they haven’t yet been exposed to modern diseases and diets that come soon after permanent outside contact, I would not want to exaggerate their abilities. They are what you would expect if you took a genetic cross section of humans and put them in lifetime physical training at moderate to hard levels. Most hunting is search time not pursuit, thus a good deal of aerobic long distance travel is often involved (over rough terrain and carrying loads if the hunt is successful). I used to train for marathons as a grad student and could run at a 6:00 per mile pace for 10 miles, but the Ache would run me into the ground following peccary tracks through dense bush for a couple of hours. I did the 100 yd in 10.2 in high school (I was a fast pass catcher on my football team), and some Ache men can sprint as fast as me.”


Loren Cordain, Ph.D., Professor Emeritus

Sample Menu for Endurance Athlete | The Paleo Diet

Nell Stephenson, Fitness & Nutritional Professional, Ironman Triathlete, and contributor to our newsletter was recently contacted by Details magazine to write up sample menus for endurance athletes: one for a workout day, the other for an off-day from training.

You will find other paleo-friendly menu ideas on Nell’s blog.

Endurance Athlete Sample Menu for Two-a-Day Workout

5:30 AM
Pre-workout Breakfast Smoothie- 8oz brewed, chilled, natural decaf green tea with a banana, egg white protein powder, almond butter whizzed in the blender with some baked yam on the side.

6:30 AM
3-hour bike ride on the trainer-carbohydrate gel taken every 25 minutes.

9:30 AM
Immediate Post-workout recovery drink- HOME BREW (recipe in The Paleo Diet for Athletes) – cantaloupe, egg white protein powder and glucose. Drink plenty of water- keep hydrating.

10:00 AM
Raisins (to restore body alkalinity, continue to help the body recover post workout, and prepare for the session later in the day).

11:30 or 12:00 PM
Grilled Chicken breast, flash-sautéed asparagus, drizzled with flax seed oil and an apple

3:00 PM
Natural unsweetened applesauce with chopped egg whites (to prepare for 2nd workout of the day-shift from the usual Paleolithic macronutrient ratio to the pre-workout focus on carbohydrates).

4:30 PM
Sixty-minute track workout-hard, fast intervals; carbohydrate gel taken immediately post as recovery.

5:45 PM
Banana (high glycemic fruit choice to, again, aid in recovery)

6:30 PM
Poached wild salmon on a bed of steamed kale, mixed green salad, avocado & sliced strawberries, a squeeze of fresh lime juice and a splash of cold-pressed extra virgin oil; sliced oranges on top.

Endurance Athlete Sample Menu for Off-Day from Training

6:00 AM Breakfast
Poached Cod (or Barramundi) on bed of sautéed spinach (with garlic & olive oil), fresh blueberries and strawberries.

9:00 AM
Steamed broccoli, drizzled with cold pressed flax seed oil, sliced orange and chopped egg whites.

Mixed green organic salad, with olive oil and lime wedge, served with grilled chicken, avocado and grapes.

Afternoon Meal
Sliced lean turkey breast used as a wrap, with Mache lettuce, raw almond butter and sliced pear inside.

Kangaroo Kebabs-lean meat, skewered with red onion & yellow bell peppers, marinated over night in olive oil, lemon juice & your favorite herbs, then grilled or broiled. Serve with grilled green onion and a fresh spinach salad with tomato, walnut oil & a lime wedge.

Cinnamon dusted sliced apples-slice an apple, toss in lemon juice to prevent browning/oxidation, then sprinkle cinnamon on top. Enjoy with a cup of herbal or green decaf tea!

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