Marathon Training Diet

BY Hal Higdon

How much should you be eating and which foods you should introduce into your marathon training diet? Hal Higon shares his thoughts...


I am currently training for my first full marathon in October. I completed a half marathon this past Sunday, but I am unsure how much I should be eating and which foods I should introduce into my diet as I move into more and more intense long runs? I weigh 127 pounds, stand 5 feet 3 inches tall and am healthy, although a picky eater. Typically, I eat an English muffin with a tablespoon of peanut butter for a pre-workout breakfast, a chocolate chunk protein bar, and grapes post-workout. For lunch, I eat strawberry yogurt, hummus and pretzels, string cheese stick, cashew cookie, and a dash of green pepper. For a snack, I might have a rice cake with peanut butter or fruit. For dinner, I usually have a bowl of rice, chicken and a salad. All this washed down with 80 ounces of water throughout the day! That is about 1,500 daily calories during the week. On my long-run days, I do eat more, usually at least 2,000 calories along with what I ingest during my long run. I am unsure if there is a meal plan for me to look at to get an idea of what improved nutrition for me might be.


I try to avoid posing as a food expert because I do not have an RD (for Registered Dietitian) behind my name. My immediate reaction is that you need to consult one. It is my continuing opinion that dietitians are among the most overlooked sports professionals for runners when it comes to improving performance while learning to eat better.

Nevertheless, I have fairly strong opinions on the foods that runners eat: both what foods and how much of those foods. Without trying to analyze your meals, it seems to me that 1,500 or even 2,000 calories are coming in a little on the light side if you plan to maintain weight en route to a marathon. Yes, you want to maintain weight, more than lose it. Consider that when you do a 20-miler, you theoretically burn 2,000 calories. That doesn’t count the number of calories you burn the rest of the day. Even breathing in and out burns calories. Furthermore, a high percentage of calories consumed should come from complex carbohydrates. I recommend 55% carbohydrates, 30% fats, and 15% proteins. Stay away from fad diets that stray too far from these numbers.

Also, 80 ounces of water seems excessive. At one point, various nutritional gurus used to recommend drinking a lot of water for reasons I can’t recall. It’s my impression that this sort of advice no longer is supported by Science.

A nutritionist might be able to offer you a more studied opinion on the subject of foods and fluids for runners. For further advice from someone who does have an RD behind her name, consider Nancy Clark, RD. Anyone who wants to learn more about what foods to eat while training needs to purchase a copy of Nancy Clark’s Sports Nutrition Guidebook. And let me emphasize again: Seeing a Registered Dietitian is something that a lot of runners should do if they are looking to improve nutrition and performance.

The Complete Marathon Training Guide

Complete Marathon Training Guide

Training Guide

This guide is designed to be used as you train for a marathon, with in-depth information on every part of the process. Each chapter is packed with tips, workouts, and insights from expert running coaches, to give you all the tools you need to succeed.

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About Hal Higdon

Hal Higdon is a Contributing Editor for ‘Runner’s World‘ and author of 34 books, including the best-selling ‘Marathon: The Ultimate Training Guide’. He ran eight times in the Olympic Trials and won four world masters championships. Higdon estimates that over a quarter of a million runners have finished marathons using his training programs, and he also offers additional interactive programs at all distances through TrainingPeaks. Hal uses TrainingPeaks to power his interactive marathon and half marathon training plans — check out more of Hal Higdon’s training plans on his website.