Diet & Nutrition tips for Marathon Training

A proper diet is an essential part of your marathon training program. It can have a big influence on your marathon race result. This page discusses some key nutritional aspects of marathon training.
Let’s look at some basic nutritional guidelines first:


What to eat

I think we are all aware of the importance of eating fresh produce, and getting the right combination of protein, grains and fruit and vegetables. Salads and raw vegetables are especially beneficial because they have not lost any nutrients due to cooking. Fish and chicken are better than red meat. Whey and soy products are a good substitute for animal protein. For the non-vegetarian eaters, I recommend having a ‘vegetarian’ day at least once a week. Your goal as a runner is to make sure you eat the best combination of foods to maintain a healthy body.

What not to eat

All the bad things you hear about fast foods are true! They shouldn’t be part of your marathon training diet. The amount of saturated fat and low quality carbohydrates in fast foods will not help your training, and in excess will be detrimental to your overall health.

When I line up for my morning coffee it’s easy to spot the people who have had too many donuts for breakfast over the years! Frozen meals as well have lost a lot of their nutritional value due to the preparation process. Ever notice the sorry-looking broccoli you find in some of the ‘dinner’ plates?

Finally those two standbys, coffee and alcohol, should only be consumed in moderation. Consensus decision-making is not easy, but the rewards you will reap from a group perspective are priceless.

How much is enough?

When I’m not marathon training I prefer a lower carbohydrate based diet. You need to assess the intensity of your own training. If you are looking to run a faster marathon and have high weekly mileage you need to have a fairly high carb intake. My recommendations in terms of percentage of your calorie intake are as follows:

1.        50 – 65 % calories from complex carbohydrates
2.        15 – 25% calories from fat, unsaturated as much as possible
3.        20 – 25% calories from protein. Use the higher percentage if you are weight training

Of course this could vary a lot, depending on serving sizes. Usually though we often end up eating too much animal protein, which can be hard on your system if you overdo it.


When training at high intensities and for prolonged workouts adequate levels of sodium and carbohydrate replacement is necessary due to sweat loss.  This is how it's done:

  • Hydrate 2 hours before activity, if not water, juice diluted half with water, or a sports drinklacking simple sugars or diluted.
  • 10-15 minutes before activity, avoid juices because of the fructose content which can cause upset stomach.
  • During activity, no juices or fructose. Diluted sports drinks are allowed.
  • Always remember, sugar slows water absorption.
  • Sports drinks are better after exercise because of mineral and electrolyte content, but still may be diluted to increase water absorption rates.

So how have you changed your diet for marathon training?   Please share your thoughts or tips on what is working for your training.  Looking forward to hearing from you!