I Read Matt Fitzgerald’s The Endurance Diet & You Won’t Believe What Happened Next!

If, like me, you suffer from a lifetime overload of dietary (mis)information, but love to read about running and food and science, then Matt Fitzgerald’s latest book The Endurance Diet will be a refreshing read. Fitzgerald travels the world, examining the diets of elite endurance athletes, and concludes — perhaps unsurprisingly — that carbs are the basis of virtually all elite endurance athletes’ diets. Furthermore, elite athletes don’t restrict calories, food groups, or macronutrients; they eat what they need to perform.

Fitzgerald’s Endurance Diet Theory

Fitzgerald identifies five basic dietary rules for top performance, and they’re all in the same refreshingly commonsensical vein:

1. Eat everything. Focus on “high quality” foods (more on these in a minute), but don’t cut out “low quality” foods entirely.

2. Eat quality. Six high-quality food groups comprise the majority of elite athletes’ diets: Fruits, vegetables, nuts/seeds/other healthy oils, unprocessed meat and seafood, dairy, and whole grains. Black coffee, tea, 100% fruit and vegetable juices, and one glass of wine also count as high-quality. Low-quality foods are sweets, refined grains, processed meat, deep-fried foods, and sugary/artificially sweetened or alcoholic beverages (apart from the first glass of wine. Hooray!)

3. Eat carb-centered. Fitzgerald found that elite endurance athletes in every country he visited based their diets on carbohydrates. Kenyan runners eat the most carbs, and it turns out there’s a sound physiological reason to do so. Carbs are fuel, but they also mitigate the effects of training stress – muscle damage, immune system problems, hormone imbalances – on the body. Eating high quality carbs like fruit and whole grains is key for endurance athletes.

4. Eat enough. Fuel your performance. Fitzgerald found that elite endurance athletes eat mindfully, paying attention to their appetite, so that they eat enough to fuel their intense training. Eating this way, they don’t have to worry about eating “too much” and slowing down from body fat gain – a common worry among amateur athletes that can lead to restrained or restricted eating and hence underfueling for performance.

5. Eat individually. Do you have allergies, intolerances, specific likes or dislikes, do you love or hate to cook, do you prefer ethically- and locally-sourced food? It’s not about finding the “perfect diet”, Fitzgerald says, but a lifelong process of staying in touch with your needs and preferences to make sure you fuel the best way for you.

The bulk of the book is based on Fitzgerald’s findings from interviewing and spending time with elite athletes around the world, but it turns out that all of his conclusions from this field study are backed up by peer-reviewed lab research. Fitzgerald describes this in evolutionary terms, drawing parallels between the evolution of training methods and of the optimal endurance diet: “Championship-level competition ruthlessly exposes what works and what doesn’t. Athletes who train with superior methods win; athletes who train with inferior methods lose — and then trade their methods for those of the winners.” Elite endurance nutrition is a product of the same processes, he maintains, evolving to reflect “the optimal diet for endurance fitness.”

It’s Not That Kind of Diet Book

Fitzgerald is a coach and nutritionist, so he knows quite well how hard it is for amateur athletes to cut through the nutritional bullshit we’re bombarded with every day, and that tips like “just eat more mindfully” are easier said that done; the book also includes practical tips for how to incorporate each of the five rules into your life.

I admit, I loved this book because it confirmed what I already thought about my own diet in relation to my running performance. Not that I’m in any way elite — far from it — but I just can’t any more with the trendy diets, the meal-replacement shakes, the supplements. Gimme all the carbs, but don’t skimp on the olive oil.

I would rather eat fossilized algae with a spoon than count a single calorie or give up a food group. And yet a small part of my brain is still storing all the useless, counterproductive diet information I’ve heard in my life. Fat bad, carbs good? Or fat good, carbs bad? Or calories evil? Whatever it is you eat (and this applies to so many daily activities as a woman) you can conjure up some negative, shaming message about it that you heard at some point and can’t seem to forget. The Endurance Diet is a great antidote to all of that.

It’s the Quality, Stupid

What I do want is to give my body what it needs to train and race hard. Fitzgerald has developed a system for scoring your diet in order to track changes and improvements, called the “Diet Quality Score”. Each food type has a point value, and the value of each type decreases depending on how many times you eat it in a given day. For instance, the first serving of dairy is worth 2 points, the second and third servings get one point, the fourth gets zero, and subsequent servings get negative points. In order to maximize your score, you have to eat a wide variety of high-quality foods and minimize your intake of low-quality items.

The highest possible number of diet-quality points is 35, but most elite athletes score in the mid-20’s, Fitzgerald says. I was curious about the app, and I thought that tracking what I ate could help snap me out of my bad habit of skipping lunch on work days. Conveniently, it’s available in an app called DQS. I downloaded it and started tracking.

I’m really not into counting calories or measuring out preordained “serving sizes”, so the self-directed nature of Fitzgerald’s scoring system appealed. You decide what a typical serving size is of any given food for you, and then use that information to track your daily servings (if this is hard, the app does give guidelines for typical serving sizes). Consistency with serving sizes is really the only ground rule for successful use of the app.

I Tried It — You Won’t Believe What Happened Next!

OK, maybe there’s not a way to make tracking everything I ate exciting (there definitely isn’t). I’m lucky that I can afford and have access to a high-quality diet. What happened next was that I found myself paying more attention to whole grains in my diet, buying brown rice instead of white and trying to remember to make quinoa more often.

This trend went on for about two weeks, then I got tired of thinking about it so much and decided I don’t really like brown rice anyway; but my baseline consumption of whole grains has in fact increased, which can only be good for my running, right? My lunch-skipping problem basically disappeared as I paid more attention to my appetite and what my body needed at any particular time (which may also have been influenced by a rather childish need to maximize my score on the app, but it was a sustainable positive change, so yay.)

I did not track my weight or running performance during this time, but I did notice a definite link between a higher diet quality score — mostly influenced by eating more servings — and my recovery from workouts. Eating enough, and eating good stuff, makes you feel better: again, not groundbreaking, but a good reminder to pay attention.

The diet tracking experiment lasted a month. I knew it was time to stop when I started to get annoyed at giving myself negative points for, say, non-whole-grain pasta, or white rice (Really? Entire cultures subsist on this stuff!). Taking it a little too seriously, perhaps? I’ll probably use the app every so often just because I quite like tracking things in general, but once you’ve established that your diet quality is where you want it to be, it’s not necessary to use it every day.

Admittedly, tracking your diet is not for everyone. Especially those recovering from an eating disorder may find it more triggering than helpful. For me, though the takeaways may seem modest (eating enough, eating lunch, eating more whole grains), it was a helpful reminder that doing some not-very-difficult little things can really help my running and overall well-being.

Have you read The Endurance Diet? What did you think? Are you a diet tracker or more of a nutritional free spirit?

I'm a 43-year-old living in Berlin, Germany and currently training for the 2020 Berlin Marathon.

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  1. I really like that Matt’s fighting the good fight against all the crazy extreme diet advice out there. It’s hard to sell the concept of balance, I guess. But I’m glad he’s trying to. Yes, the standard american diet as a whole is not healthy (processed meat, refined grains, sugars, additives, etc). But that doesn’t mean some other knee-jerk extreme is good (nothing but organic plants). In general organic plants are more healthy than hot dogs, but only eating organic plants is not necessarily morally superior or healthier than a more balanced approach. And I like that he talks about other considerations that determine health, like mental health and the social elements of diet. Will my health deteriorate if I eat the velveeta my 90 year-old grandma put on my sandwich? No. And the occasional velveeta makes real cheese taste better 🙂

    1. Yes to all this! I also like his emphasis on the fact that there is on one size fits solution – you have to find out what works for your body.

    2. I agree with this! I haven’t read his book YET but I probably will once I need to shed the baby weight. I do like the idea of balance though. I hate fad diets; are they sustainable? I know some people need to go to the extreme to lose weight; I totally get it. But if it’s that much of a stretch for you to stick to the diet itself, is it going to be sustainable? Balance is so important! And yes, velveeta is amaze-balls 🙂

  2. I love this advice! There’s so much extreme dieting right now, it’s making everyone crazy…and none of it is sustainable in the long term. My in-laws are on this no carb/grain brain kick (for the last 3 years) My hubs and I tried it for a month. We were exhausted, grouchy, running was a slow death march, but my abs have never looked better. Ultimately, the price for beautiful abs was too high for us, so we went back to enjoying our normal, relatively healthy/balanced diet.

    1. Oh my gosh, I gave up grains for like three weeks back when paleo was first a big deal. It was terrible for my running!

  3. I like the simplicity of the DQS system. I’ve used it a few times while marathon training to motivate me to set some healthy habits. I didn’t know there was an app – thanks for the heads up!

  4. I’ve been pondering his book “Racing Weight” for a few months now mostly because after losing 94lbs, I would like to lose the remaining 30 pounds while also not messing with my running goals for the year. Plus, I thought it might help me transition into regular old, new me. After reading your review, I think maybe I’ll get this one instead. I didn’t know there was an app. I have a love/hate relationship with MyFitnessPal mostly what I eat doesn’t come in a package and the tedious nature of entering every little things drives me batty. I have used it off and on over the last four years while losing the bulk of the weight. MFP and I are currently in an “on” phase. His DQS from the bits and pieces I’ve read about it seems like it would be more valuable to me at this point than MFP which seems to default lean towards the “carbs are bad” paradigm.

  5. I feel like everyone I know is doing Paleo, or Whole30, or some other highly restrictive diet. My favorite is the inevitable “I reached 30 days and now I’m eating all the chocolate and wine!” post on facebook when the diet “ends”… I have always had a problem with anything too restrictive, mostly because it makes me fixate on it and I get obsessive. I can’t count anything – calories, servings, carbs, etc…. Now I’m obsessive about moderation… which I think in the long run works better – for me, and probably for most people. I really liked Racing Weight, and I’m interested in this book too although it sounds very similar.

    1. I haven’t read this one, but I’m guessing it’s like if you took Racing Weight and Diet Cults and smashed them together. Haha! (And I enjoyed both of those.)

      Matt also has a Runner’s Diary logbook that includes an area to track DQS.

  6. It’s no secret I’m a Matt F. fan, although I haven’t dived into this one yet. I used the DQS system for a while because it’s also part of the Runner’s Diary he authored (https://www.velopress.com/books/the-runners-diary/). When I decided to get back into competitive running (and was getting married), I wanted to lose some weight and used the LoseIt app. Being a typical type-A perfectionist, I not only wanted to log everything but I wanted to somehow WIN at it. And it really just complicated my life. What if I just wanted to cook something and not use a recipe that had all the calories calculated? Ain’t nobody got time for that. Anyway, now that my weight is where I want and tends to stay pretty stable, I don’t normally track. However, sometime during that weight-loss phase I decided to eat vegetarian except for dinner (a really lazy version of Bittman’s VB6) to encourage myself to eat more fruits, veggies, and legumes. Now instead of a turkey sandwich, I have a quinoa and sweet potato bowl with black beans, or a big salad.