The Do’s and Don’ts of Marathon Nutrition

Nutrition is one of the hottest topics amongst marathon runners. Questions about what to eat before, during, and after the race are commonly asked by beginners and even advanced runners. Will I lose weight? Why am I gaining weight? Is carb-loading important? All these are valid questions. Here is a quick guide to getting your nutrition dialed in for the big race.

Just like your running, marathon nutrition should not start a few days before the race. It starts the minute you begin training. Training and diet are the two of the most critical factors determining performance on race day. Most runners spend many hours per week training, planning, and preparing their training session, but how much time do you spend on nutrition? This essential piece is often taken for granted, and can jeopardize all the hard work you have put in to achieve your goal!

So where to start?

Early Weeks

At the start of your training, your mileage shouldn’t be much more than you are already used to so you’re eating patterns should not change very much. Make sure you are eating tolerable carbohydrates before your runs; as well as, carbs and protein after your runs. A good rule of thumb for post-run recovery is a 3:1 ratio of carbohydrates to protein. Although you may feel hungrier than usual due to the increase in training, try to avoid overindulging as these early weeks can sometimes lead to weight gain.

Middle Weeks

At this point in your training cycle, you have seen an increased in mileage and started to tap into your long runs. In my opinion, these are some of the most crucial weeks for your race nutrition due to the fact that you need to see what works best for you! This means you should be testing different foods and strategies to see how your body reacts. We’ve all heard those nightmare stories of runners pooping their pants right?

This can be avoided by testing out our race day foods. So where to start?

-Make sure you are eating some easily digestible carbohydrates at least one hour before your long runs. My favorites are bananas, bagels, oatmeal, and Clif bars.
– If your long run is going to last over two hours, you need to take some sort of carbohydrate to eat during your run. There are tons of different options, most of which have 20-30g of carbohydrates in them. There is no right or wrong choice, but make sure you sample a few to see which tastes the best and agrees with your stomach. This will be crucial come race day. A general rule of thumb is to consume one packet/waffle every hour during a long run.
-Take a water bottle with you. Hydration plays a massive factor whether you feel thirsty or not.


Although it is common not to feel hungry when you finish, it is crucial to get calories back into your body as soon as possible. This doesn’t have to be a huge meal immediately, but you should consume something with carbs, protein, and a little fat. An easy go to is a fruit smoothie with protein and peanut butter, followed by a regular meal one to two hours later.

Remember everyone has different likes and dislikes, and our stomachs react differently in regards to what we can and cannot consume during exercise. I encourage you all to test out a few different methods throughout your training. If you have any questions, don’t hesitate to reach out!