Nutrition before a marathon or a trail

During a long distance run, your body uses carbohydrates and fat stores as a fuel source to keep you going. Fat stores are almost unlimited, but carbohydrate stores run out faster. It’s important to start a race with full carbohydrate reserves. Here is some advice for optimal nutrition.

It is common to suffer from digestive problems during a long race distance in a marathon or a trail. Long distance races demand hard work from your organism, over loads that increase your energy and stress for the big day. This stress is compounded, whether by an unusual distance or by the consequences of the goal for which you have trained for weeks. How can you make pre-race nutrition an ally?

Running, a pressure on the intestinal wall

During long-distance running, your heart supplies blood to your major organs such as the brain and muscles during exertion. Sometimes the intestines can be disconnected, and the numerous jolts can also cause lesions in the intestinal wall. Therefore, you need to make your digestive system work easier.

From J-10 to J-3: some principles for nutrition

Training now slows down and intensifies so that you are at your best on the big day. To be able to integrate the weeks of training before the competition, you need to have a good lifestyle with a balanced diet. Most importantly, make sure you get a good night’s sleep.

A balanced diet means eating a little bit of everything: starchy foods, protein (white meat, fish, eggs or other), vegetables, fruits, oily foods, oil with high omega-3 content (flax, canola). Do not forget to hydrate yourself! Also diversify the sources: still water, sparkling water, tea, herbal tea… Do not give up a good beer or a glass of wine from time to time, of course, if you do not overdo it.

Reduce your dietary fiber intake to avoid suffering from intestinal problems during the race. Opt for white meat, eggs, zucchini, soups…Some will prefer gluten-free foods.

To ensure a quality carbohydrate intake and optimize your diet before the race, we recommend reducing the ratio of carbohydrates and starchy foods from J-6 to J-4, without cutting them off completely (the organism may have difficulty in the transition). In this way you can reduce your carbohydrate supply before returning to high quality carbohydrates in the last days.

From J-3 to J-1: the last preparation

From J-3 to J-2, well, that’s the time to stock up on carbohydrates with high-quality nutrients and a low glycemic index. Use the time within the metabolic window of 4 to 6 hours after your refresher training/exercise session to stock up on carbohydrates.

Nutrients you should consume first include steamed potatoes with skins, sweet potatoes, semi-ripe rice, buckwheat, quinoa, honey, maple syrup…Fruits can provide fructose, which is interesting for the organism, but avoid those that contain fiber. Take ripe bananas or stewed fruits: apples, pears, peaches.

Among the nutrients you should avoir because of their high glycemic index are: overcooked pasta, white bread, sugar, French fries, cornflakes of rice cakes…

In general, you need to reduce vegetables, especially raw vegetables and dried legumes (lentils), which are really corrosive and not always easy to digest. Soups, carrots, zucchini, even vegetable juices (with juicer) are preferable and reduce the acidity of your body.

If you have to heed one piece of advice, it’s this: reduce fiber and opt for carbohydrates (without stuffing yourself!).

An optimal fluid intake 

Drink still or sparkling water or hot beverages regularly throughout the day. Even an isotonic drink may be recommended.

Avoid sodas (too sugary, they limit the absorption of nutrients), fruit juices (sugary and acidic), milk-based drinks (lactose requires a lot of energy to be digested).

Nutrition the day before a marathon or an ultra run

Stick to the routine of the previous 3 days and at best limit fiber, spices, unsaturated fats (fried foods, prepared foods, etc.) and oily foods. Be careful not to eat too much, because that would rob your digestive system of a lot of energy. And don’t eat nutrients that you are not normally used to eating.

Nutrition in the morning/day of the race or day

You need to eat 3 hours before the race (sometimes a little more). Sometimes this is pretty early, but you will not regret it! Drink water or herbal tea first before eating and don’t lie back in bed.

Only eat nutrients that you have tested before a race or training session. No one wants to gamble weeks or months before a prep race.

You will have stocked up on carbohydrates days before, so you do not need to eat much, quite the opposite.

Ideas for breakfast before exertion:

  • Tea, herbal tea, coffee, water
  • Bread, pancakes
  • Sports cake, energy cake
  • Honey, maple syrup, jam
  • Ham, tuna fish
  • Stewed fruit, sliced banana

Avoid: fruit juice (acidic, fast dissolving sugar), soda pop, raw fruit, oily, whole grain bread (too much fiber), dairy products.

Drink a little water every 30 minutes, but not too much (0.5/h maximum even 0.7l in high heat!). There is a risk of getting into hyponatremia process.

And that’s it!

You will still have time to stock up on food.

You are now ready for the start of the race, marathon, trail, ultra or triathlon. If you are looking for customized training and advice for your preparation, the RunMotion Coach app is for you. All pre-race nutrition recommendations are included in the application. On your marks, get set … go!

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Mailis Durif-VarambonMailis grew up in the mountains, where she went hiking and biking every weekend. She loves outdoor activities where she can relax at the end of the day. At RunMotion Coach, she is responsible for community management.