Fight the Bonk Part III: What to Eat Before the Marathon

Bonk (album)
Ha!  Photo Credit: Wikipedia

This is it–Marathon season is here!  We’ve been talking a lot about training, setting goals, mental tips, pacing strategies and taper tips because we Salties want to make sure you all have the best possible outcomes on race day.  We’ve also run our “Fight the Bonk” series because let’s face it, no  one wants to bonk in any race.  Today Salty and I collaborate on the subject to discuss how to adequately fuel in the days leading up to your marathon.

Despite popular convention, pre-race nutrition involves much more than carb-loading the night before the race (hello pasta!).  We need to make several smart choices to hit the start line and the finish line in ideal shape.

The Week Prior to the Race:  

Grain products are often baked, and are rich s...
Grain products are often baked, and are rich sources of complex and simple carbohydrates. (Photo credit: Wikipedia)
  1. Start carb-loading the week prior to your race.  This is particularly important the last two days before the race.  Stored carbohydrates = race day energy!
  2. But! Do not radically alter your diet.   Some used to advocate a few days of a low-carb, high protein diet before the carb-load starts, but recent studies have shown that isn’t necessary.  So keep your normal (healthy diet) and just up the carbs.
  3. Be mindful of the types of carbs you are increasing.  Too many white flour/low fiber choices (bagels, donuts, crackers) can cause constipation.  Too much fruit/fruit juice can cause diarrhea.  Both could botch the best of races so select a balance. For all you carb-loaders, Rosemary posted a great balanced and high quality carb recipe this morning. Check it out for a carb-filled healthy and delicious (and extremely packable for those traveling for their marathons!) snack!
  4. Eat your protein.  Don’t trade protein for carbs.  We need protein to continue healing our muscles.
  5. Hydrate.  We get used to living in a somewhat dehydrated state during training, and NOW is the time to reverse that.  Drink lots of water and restrict dehydrating liquids (alcoholic beverages, too much coffee).  If you’re having trouble getting hydrated, try adding extra electrolytes (like Nuun) during the days before the race.
  6. Don’t pile on the calories in the name of carb-loading.  You are running less, so you don’t need more calories, but the same amount of calories as usual is fine.  BUT if you find yourself hungry, eat!  Now is not the time to restrict because your body needs the fuel for both recovery and carb-loading.
  7. It’s Okay if You Gain Weight.  In fact, you probably will see a weight increase of 1-3 pounds.  Don’t panic.  This means you are well hydrated and fueled.

The Day Before the Race.  In addition to the above, cut out all foods that may make you gassy or may upset your stomach.  Stick to bland foods and have a salty snack to help your body hold onto extra fluids.  Some people advocate a big pasta dinner, but Salty and I prefer to have a bigger lunch and lighter dinner to avoid an over-stuffed belly on race morning.[pullquote]”More marathons are won or lost in the porta-toilets than they are at the marathon…”  Bill Rodgers, 4x Boston Marathon winner[/pullquote]

Race Morning Nutrition.  We suggest waking three hours prior to the race.  Eat a bagel with peanut butter, a banana and some Gatorade.  Yes, it is hard to wake up at 4 am and eat all that, but it’s important.   Sip on water or sports drinks until about an hour before race start.  Then stop!  Hydration is good, but you don’t want to overload and find yourself needing a pee break by mile 3.  Last, but certainly not least, take a gel 10-15 minutes before the start of the race.

Racing Nutrition Reminder.  We all know it is important to take in water, sports drinks and gels during the race.  There are calculators and strategies to figure out just how much we need.  But one concept is universal:  you want to take in as much as you can early in the race.  If you wait too long to take those gels, they’ll be less effective.   Create and execute a nutrition strategy that is front-loaded to stave off glycogen depletion and its resulting pain.  The amount you need will be dependent on conditions; for instance, you’ll need less if it is cold than if it is 70 degrees.   Final tip:  when taking gels, drink water – NOT sports drink.   Water is needed to dilute and help your body properly absorb the gels.  If you take Gatorade + gel, you very well may end up with a serious stomachache, so don’t do it!

That’s it.  Go get ’em!  Do you have any other tried-and-true pre-race or race-day strategies to share as race day approaches for so many of us?

Mindi is a serial marathoner. She is a private practice attorney, wife and mom of two awesome (and super fast) boys, ages 12 and 14. She coaches Girls on the Run and is a big advocate of youth running.

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  1. Just like last week, this post is exactly what I needed. Before marathon training, I never thought about what I ate before or during a race – even half marathons. After a couple of bathroom dashes during my long runs, I realized how important it is to get it right. Thanks Mint, for nailing it down for me.

    1. Another option I like is an energy bar. They are full of good stuff, yet bland and easy to digest. Just make sure you eat one that you have tried before. I know you’ve heard it before, but never try anything new on race day – particularly with food/drink/gels.

    2. I like Clif Bars too. Any fruit is high in carbs. Maybe some cantaloupe would be good if you want some fruit. That probably would be mild enough and not too high in fiber. Definitely try before a long run before eating it the day of the race though, just in case!!!