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Running a Marathon? Tips for What You Should Be Eating and Drinking

by Athletico2 Comments

Here it comes! Many of you have been hard at work training for your upcoming marathons, and it’s finally here! I’ve been getting a lot of questions regarding hydration and nutrition. The following post will focus on the most common questions I’ve received.

What is carbo-loading and should I do it?

Carbo-loading is not just going to a pasta party the night before your race. Done properly in the week leading up to your race, it can create glycogen stores in your muscles that can really enhance your energy levels during your race. When you eat carbohydrates, they are broken down into simpler sugars like glucose.  Any simpler sugars not used right away are stored as glycogen.  Glycogen is the source of energy most often used in exercise.  It is easy for your body to break down and use for energy.

  • As a general guide, during non-race weeks, 60% of an endurance athlete’s total calories should be carbohydrates.
  • A week before the race, adjust your complex carbohydrate consumption to 50% of your total calories. Eat more protein to make up for this decrease in carbohydrates.
  • Three to four days before the event, increase your carbohydrate intake to about 70% of your daily calories. You should be eating complex carbohydrates like whole-wheat pasta and bread, vegetables, and low fat dairy products—not Twinkies and potato chips!  Try to eat 4.5 grams of carbs per pound of body weight if you are a female or a smaller man and 3.5 grams per pound of body weight if you are male or a larger woman.  Eating low fat at this stage will give you more room for glycogen storage. Take it easy on the training to avoid burning off the carbs you are storing.
  • Don’t drink a lot of alcohol the week before a race as it affects how your body metabolizes carbohydrates, and it will dehydrate you as well.

How much water/sports drink should I drink?

Recently there have been more articles about the danger of hyponatremia—a metabolic condition in which there is not enough sodium in the body fluids.  This condition can occur if you drink too much water and you excrete your sodium stores.

These articles recommend you only drink when you are thirsty.  I feel it’s extremely important to elaborate on this statement.  When you are running a marathon, you will get to the point that you are very tired and your mental acuity is not at its normal level.  You could very well believe that you are not thirsty and in fact are becoming dehydrated; therefore, thirst is not always the best indicator of when to drink.

My suggestion is to drink at the same levels you normally do in the week leading up to your race.  Try to cut back on caffeine a bit but not entirely if you normally consume caffeine.  On race day, drink at the level you do during your long runs. Your training runs are great dress rehearsals for race day.  Think about how much you drank on a hot day or a particularly cool day.

One really good gauge of hydration level is the color of your urine.  If it looks like lemonade, you are right on target.  Too dark means dehydrated, too clear means back off on the liquids.

When and what should I eat on race day?

Again, this is something great to practice on long runs to see what your body will and will not tolerate.  My friends call me Rainman because I always eat a peanut butter and banana sandwich on whole wheat bread.  I traveled to France for a race and brought peanut butter with me so I could have my “brand.”  That said, everyone digests differently, so don’t try anything new on race day.  Here are couple good rules of thumb:

The Night before the Race

  • Eat something bland that is high carb and low fat.
  • Again:  Don’t try anything new.

Race Day

  • For the third time:  Don’t try anything new.
  • Eat 3 to 4 hours before the race starts.
  • Eat 200 to 400 calories of high carb, low fiber, and low protein foods. Some examples include peanut butter and banana on whole wheat sandwich, Kashi and low-fat Greek yogurt, and energy bars.
  • Avoid fatty foods.

During the Race

  • Alternate sports drink and water at the rest stops.
  • Try gels, blocks, etc, BEFORE race day as all the different forms do not agree with everyone.
  • If they do agree with you, take them every hour to hour and a half.
  • NEVER, EVER, EVER drink a sport drink and gels/blocks at the same time!!!  Most people are very nauseous when they combine these two items.

After the Race

  • Low-fat chocolate milk is the best recovery drink.  People think I’m kidding, but the Mayo Clinic, USDA, and NCAA have all done studies that have concluded that there is nothing better.
  • Salty foods like pretzels and potato chips are a good choice.  Salt helps your body retain water, which leads to less dehydration after your race.
  • High carbohydrate, easily digested foods are the best bet.   Bagels, bananas and sunflower seeds work really well.  During the race you will use up your glycogen stores.  Because insulin (the hormone that delivers sugar to your tissue) is slightly elevated during a marathon, your body more efficiently stores glycogen in the hours immediately following your race.  Replenishing your glycogen leads to a faster recovery.
  • Eat frequently!  You need it to recover, plus it’s fun!

Speaking of fun:  enjoy your race and celebrate your accomplishment. Whatever your race goal is, be proud! When you cross the finish line, you are among only one percent of the American population that has completed a marathon. Wear your medal everywhere.

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The Athletico blog is an educational resource written by Athletico employees. Athletico bloggers are licensed professionals who abide by the code of ethics outlined by their respective professional associations. The content published in blog posts represents the opinion of the individual author based on their expertise and experience. The content provided in this blog is for informational purposes only, does not constitute medical advice and should not be relied on for making personal health decisions.

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  1. Candice Reimholz

    Thanks Ally.I am going to recommend this post to all my massage clients that are running the marathon.

  2. robert Newell

    My name is Robert Newell and I am competing in the belfast marathon this year. I would have alot of trouble with cramps after running, I am eating alot of food containing potassium, would anyone have any other tips to stop cramps after running??

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