Gut Check: 6 Strategies to Stop GI Distress from Ruining Your Event

‘This race will take all of the grit, guts and determination you have’. I can remember these words being belting out over the loudspeakers by Leadville Trail 100 race director Ken Chlouber in front of a packed gymnasium of nervous athletes. While Ken was most likely referring to one’s character, the ‘guts’ part of his speech can now take on a more literal meaning thanks to Dr. Martin Hoffman, who published a study in the International Journal of Sports Physiology and Performance. And although the study specifically examines ultramarathoners, the findings – and the pieces of advice below – are relevant to any athlete participating in long-distance training sessions or events.

The study examined the factors related to the successful completion of the Western States and Vermont Trail 100 mile runs. Utilizing a post-race questionnaire, the researchers looked at host of factors – including training volume, maximum long run volume, the use of NASIDs, age, BMI, years of experience, number of 100 mile races completed and others – to determine what correlations can be made for those who finished vs. had to drop out (or ‘non-finishers’, as the researchers dubbed them). As a coach and ultramarathoner, their findings were somewhat surprising and interesting. One of the most interesting findings was the havoc nausea and/or vomiting causes for both finishers and non-finishers during the events. When the non-finishers were asked what caused them to withdraw, 23% reported ‘vomiting and/or nausea’ as the culprit, more than any other factor. As a comparison, the total number of people citing injury, blisters, muscle cramps, and exhaustion was only 21.6%. This means that more people dropped out of the two races due to GI distress than injury, blisters, cramps and exhaustion COMBINED! WOW!

As it turns out, even the finishers were not immune to GI distress. In fact, both the finisher and non-finisher groups reported nausea and/or vomiting as their top 2 responses when asked to choose ‘problems that impacted race performance’ (at 36.8% and 39.6% respectively). As the researchers point out, preventing and minimizing GI distress is a critical, if not the most essential, success factor in a 100 mile ultra marathon. As a coach, this is encouraging because most GI distress is preventable with proper training and nutrition.

Here are a few tips I use with my athletes – ranging from cyclists to triathletes and marathoners to ultramarathoners – to get the most from their guts.

Practice makes perfect

At least twice per week, preferably during your longer workouts, you should practice your game-day nutrition plan. Make sure to go through the whole plan during the training at some point. If you plan on switching from gels to real food during the race, then practice that and see how you react.

Find Your Gut’s Limitations

All competitors want to go fast and want to go long. They push their bodies in these areas. However, most of them do not push their guts to see what they can tolerate. I’ll revert to the research: only 0.7% of non-finishers reported ‘inadequately trained’ as the reason for the dreaded DNF (that’s not a typo: point-seven percent, less than 1 percent). A whopping 23 % cited nausea as the offender, nearly 33 times the amount of ‘inadequately trained’. So if you want to finish, you need to train your stomach as well (if not better) than your lungs and legs. I have my athletes do this by taking in more calories than they usually do in at least one training session per week. If you normally take in 200 calories per hour, try 300. Try to find the limit of what your gut can accommodate and perform well with, and then test those limits.

Find the exceptions

We spend a lot of time planning nutrition strategies for athletes, but rarely does an event-day nutrition plan happen exactly as you’ve drawn it out on paper. That’s why part of the “planning” has to include what do when the plan goes awry. You better know what types of foods and fluids you can switch to. Do this by experimenting with different foodstuffs and drinks during training. What you are looking for are the things that definitely won’t work. That way, when you come up to the aid station buffet line at mile 80, you’ll know what one or two things to pick up out of the hundreds of options normally available. My favorite way to do this is to buy calories and fluid from grocery and convenience stores along my long workout route.

What do when your gut goes sour

As the research points out, GI distress is a big problem during ultradistance events. Some of these issues may be more pronounced for ultramarathon runners because of the physical jostling of running and the duration (24-30 hours), but athletes in shorter events still suffer from the same issues. Although you can prepare, train, eat and figure out the best nutrition plan possible beforehand, the inevitability is that you can still get a sour gut at some point during a long event. If you do, don’t panic, there are things you can do to cope. Remember, 36.8% of the finishers in the study reported GI distress during the events. This means that over a third of the race field finished despite their guts being in knots at some point. There are a ton of tips, concoctions, pills and other remedies out there on how to deal with a topsy-turvy stomach on race day. The ones that I have found to be most effective are:

Slow down:

Your stomach is always competing with your working muscles for blood flow. Part of GI distress is not having enough blood flow to the guts to properly digest food. If you can slow down, you can alleviate this by moving blood from your working muscles to your digestive system. Once your guts clear up, you can pick the pace back up! Better to slow down for 15-30 minutes than to come to a complete halt later on.

Cool off:

Similar theory as above… blood flow is getting pulled toward the skin’s surface for cooling, thus moving away from the digestive system. Use an ice-filled bandana and dunk your hat in the nearest stream to keep yourself cool.

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Slowing down and cooling off are essentially universal advice for dealing with GI distress, in that they should work – to some extent – for anyone. When it comes to food/fluid/medication remedies, I can only tell you what has worked for me and the athletes I’ve worked with, and that’s ginger. It comes in a variety of forms; crystallized, candied, pickled, raw, etc. I suggest trying them all in training and having the variety of your favorite choices in either your drop bags or in your hydration system. Take small doses when you begin to get queasy.

By Jason Koop,
Head Coach of CTS Ultrarunning, Author of “Training Essentials for Ultrarunning”

For more information on the research cited above, please refer to-

Hoffman MD, Fogard K.  Factors related to successful completion of a 161-km ultramarathon.  Int J Sports Physiol Perform 6:25-37, 2011.


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