It’s no secret that nausea and ultrarunning are common acquaintances. Even the world’s best trail and ultra runners can be found hunched over heaving up electrolytes during a race.

Some runners choose to brag about spewing as if it’s a badge of honor, and proudly proclaim that you aren’t racing until you’ve seen last night’s dinner a second time.

Hell no. I have a different opinion.

While nausea is very common during an ultramarathon or endurance races, I consider it a sign that you’ve done something wrong. And you should do everything you can to avoid it.

No badge of honor. Nothing to brag about.

So if it’s that common, what can we do?

Thankfully there are a number of ways to address and prevent nausea during your next race.

How Nausea Can Ruin Your Race

Nausea has a way of turning a great run into a terrible run in a matter of minutes. As quickly as you can blast down a hill, nausea can step in and reduce you to walking, or worse, dropping all together.

During the final hours of the 2015 Black Mountain Monster 24 hour race I was moving slow but consistent, just as I wanted. On one of my final laps, after power-hiking my way up a short hill and swallowing a swig of energy drink, boom … it hit me. Out came everything I put in over the last several miles.

Immediately I felt lightheaded and weak in the knees. My stomach flipped several times over the next mile and my mind was reduced to only thinking about vomiting again (and again).

Moving consistently became hardly moving at all — until I got a handle on my stomach.

What Causes Nausea During a Race?

Some runners may deal with nausea during a road marathon, but for the most part they can get by with little more than water and an energy gel and finish before their stomach figures out what they’re doing.

Add three, eight, twenty hours to that during an ultramarathon and the body has plenty of time to revolt against your effort, the conditions, and your nutrition strategy (or lack there-of).

So let’s take a look at what could be causing your mid-race nausea:

  • Overheating: Overheating has a trickle-down effect on your running. For one, being hot alone can upset your system, but more importantly overheating can lead to dehydration and a lack of appetite (not enough calories = nearly guaranteed bonk).
  • Dehydration: Not consuming enough water is a common problem, especially during hot or humid summer races, and will almost certainly lead to stomach and nausea issues.
  • Water to electrolyte imbalance: On the flip side, if you’re taking in too much water and not enough electrolytes, or popping too many salt caps and not enough water, the imbalance will leave your stomach with just as many problems.
  • Running too hard: Running harder than normal due to the race atmosphere? That upset stomach may simply be a sign of overexertion.
  • Not eating enough: The empty, hollow, nauseated stomach feeling many runners feel late into a race is often due to not taking in enough calories.
  • Eating too much: Nutrition plans and hourly calorie goals are all well and good, but if you’re taking in too much nutrition for your increased level of racing effort, it will upset your stomach.
  • Too much of the same foods: I generally like to keep my nutrition plan simple, especially on shorter distance ultramarathons. But strictly sticking to gels or energy gummies can quickly flip your stomach if you haven’t trained for it.
  • New foods: Roll into an aid station hungry and it’s tempting to scarf down anything that looks tasty, but that decision to try new foods mid-race may come back to haunt you a few miles down the trail.

6 Tips for Preventing or Dealing with Nausea

Yikes. That list looks a little dire, am I right? Not enough water, too much water. Not enough food, too much variety …

It’s no wonder so many runners deal with nausea during a race.

But there are ways to not only stop nausea from taking over your race, but prevent it from arriving in the first place. Here are my tips for how to do just that:

1. Practice

Just like you train your muscles and mind for race day, you also need to train your stomach. Use your longer training runs to mimic race day as much as possible, including what you eat before and during the race itself. Running a hot race? Practice dealing with heat during training.

Running a fast race? Train yourself to eat and convert calories throughout each and every long run.

Test and retest your nutrition strategy against race-day conditions as much as possible before going into your goal race.

2. Slow Down

If nausea hits, don’t panic. The first step to getting it under control is simply to slow down to an easy pace or hike. You’ll be amazed at how many issues a reduced pace can address in a short amount of time.

And always remember, it’s better to lose 5-10 minutes and address the issue now than waste 45 minutes later in the race because it got worse. That goes for nausea and anything else that might be causing a race-day problem (like blisters and chaffing).

3. Keep Eating and Drinking

With an upset stomach, especially if you feel like you need to vomit, the thought of eating and drinking may be straight up repulsive. But that’s exactly what you need to do.

Continue eating and drinking even when you don’t want to. Slow down to a hike or jog and try to catch back up on any calories or hydration you may have missed.

Story Time: Late night hours of Thunder Rock my pacer reminded me I hadn’t eaten in a while. I felt gross, tired, and completely over gels and gummies. But I knew I had to. Instead of eating one or two gummies I went ahead and bit the bullet, stuffing 5 in my mouth and slowly chomping until they all went down. It took a while, but sometimes you’ve just got to do what needs to be done.

4. Puke if You Have To

I would never advocate for anyone to intentionally vomit during or outside of a race. But I will admit that relieving yourself will almost immediately make you feel better. If you think you’ve got to spew, let it go (off the side of the trail please … don’t be that guy).

Then begin replenishing the lost liquids and nutrition.

5. Coke, Sprite, and Ginger

Some people say that soda or ginger chews help with nausea. If it helps to have a little soda or to chew on ginger, go for it.

The soda may cause you to burp, which could relieve some of that pressure and stomach discomfort, and ginger is known to ease stomach pains and nausea.

6. Salt

If your stomach is cramping, electrolyte tablets or salt can help. Just make sure you’re balancing it out with water consumption.

7. Soothing Foods

If you’re feeling nauseous due to over-doing the energy gels or sugary foods, indulge in an aid station comfort food instead. My favorites are:

  • Warm vegetable broth
  • Crackers
  • Fatty PB&J sandwich
  • Boiled potatoes dipped in salt
  • Oily potato chips
  • Oatmeal

Scan the aid station for what looks good and give it a try.

Don’t Let Nausea End Your Race

Let’s face it, occasionally there are bouts of nausea that can and should be race ending. If you can’t keep anything down or simply feel far too weak to continue on, it may be a good idea to pull the plug.

But — and this is a big but — most of the time nausea can be addressed and cured.

Take precautions going into the race and on race day, and be smart about how you handle nausea if it comes.

When all else fails, remind yourself that the majority of other runners around you will feel just as terrible at some point doing their race.

And if they can get through it, so can you … even stronger.


Author Doug Hay is the founder of Rock Creek Runner, host of the Trail Talk podcast, and fanatical about everything trail running -- beards, plaid shirts, bruised toenails, and all. He and his wife live and run in beautiful Black Mountain, NC.

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