After months of hard training, every runner wants to perform their best on race day. There are a few culprits for a bad race – inclement weather, poor pacing – but few seem to strike as often as gastrointestinal distress. Whether it manifests as nausea, vomiting, mid-race bathroom stops, or cramping, research published in Human Kinetics Journals suggests that up to 90% of runners experience symptoms of GI distress on race day.
Severe GI distress can play out in one of two scenarios on race day:
- You stop fueling, which leads to bonking or fading later in the race.
- You have to make several bathroom stops and slow down, add several minutes to your finish time and prolonging the discomfort.
Neither scenario is desirable. You will not perform your best or enjoy the race if you have an upset stomach or bonk.
Why does GI distress happen on race day?
- Increased nerves
- Higher intensity of racing means more blood flowing to working muscles, less to GI system
- Longer duration (for the marathon) stress the body – including the GI system – more
- Your fuel of choice doesn’t sit well with GI system
All the extra excitement and effort of race day means that your stomach is more sensitive on race day. A gel you can stomach in training might not sit well on race day. Ultimately, you want to find fuel that works for you on race day – because that is when fueling matters the most.
For most runners, the answer is not to skip fuel altogether, especially in the marathon. A few runners possess the endurance and ability to metabolize fat well enough to forgo any calories during the race, but those runners are the minority. Most runners will find that fuel optimizes their half marathon performance (when running for over 80 minutes) and prevents bonking during the marathon. If skipping food is not an ideal option, then the solution comes down to picking a better fuel option for you.
If traditional gels work well for you, there is absolutely no reason to change them. However, if you experience nausea, the need to stop for the bathroom mid-race, cramping, or other symptoms during a race, it is worth experimenting with different types of fuel.
Gels can be difficult to digest, thanks to both their composition and ingredients. Some runners struggle to digest fructose, a common ingredient in gels. Maltodextrin is another common ingredient in gels; while it’s easier to digest than fructose, it still doesn’t work well for all runners. Whether fructose or maltodextrin, gels are highly concentrated carbohydrate solutions and require water to digest. Without enough fluids (or sometimes even with), those concentrated solutions will sit in the gut, causing GI upset and not providing the vital energy you need.
Race Day Fueling Options for Sensitive Stomaches:
Alternative Gels: Not all gels are formulated with maltodextrin and fructose. Some brands use honey (glucose and fructose), cane sugar (sucrose), brown rice syrup (basically glucose), and/or maple syrup (sucrose) to provide carbohydrates. Some runners may find that glucose and sucrose are both easier to digest and taste better. As with any gel, you want to consume these with at least a mouthful of water – otherwise, you will be bombing your stomach with concentrated carbs.
- Honey Stinger
- Spring Energy Gels
Chews: Chews also have the benefit of letting you spread your calorie intake out more. Rather than taking whole gel every 40 minutes, you can take one or two chews every 15-20 min.
If your stomach is very sensitive, check the ingredients. Some brands use the same ingredients in their chews as in their gels. The following brands feature easy to digest ingredients such as cane sugar, fruit juice, honey, and tapioca syrup:
- Honey Stinger Chews
- Skratch Lab Sport Energy Chews
- Glukos Energy Gummies
Liquid Options: Think beyond saccharine Gatorade here. Several new sports drinks are formulated to provide enough calories for energy without requiring much digestion.
- Generation UCan
- Tailwind Nutrition
Whole Foods: If the sugar of gels and chews unsettles you, try whole foods option instead. For some runners, the macronutrient variety of whole foods (not just simple sugars) improves digestion and prevents energy spikes and crashes. Read more on fueling with whole foods in this post.
- Honey Stinger waffles/Stroopwafels
- Cut up PB&J sandwiches
- Energy bites
- Picky Bars or Clif Bars
- Dried fruit
- Boiled potatoes/sweet potatoes
Candy: Yes, candy. While not exactly a whole food, candy isn’t a sports nutrition product either. However, candy such as jelly beans, gummy bears, Swedish Fish, and Starburst are all options. If you do not mind chewing and enjoy the boost of sugar, candy is worth trying.
No matter which type of fuel you use, always practice before race day to ensure it works for you.
Obviously, there can be other factors that contribute to GI upset, including dehydration, chronic stress, medical conditions, or poor pacing. However, it is often the simplest solution that is the correct one: if your stomach gets upset after you eat your fuel during a race, try a different fuel.
If you want to learn more about avoiding GI upset during races, as well as other sports nutrition topics such as gut training, avoiding the wall in your next race, and how to use caffeine and other supplements to race, you may be interested in my Fuel Your Fastest Running E-Course! This course lasts 4 weeks, with twice-per-week email lessons and videos, plus the option to schedule a call for individual guidance at the end of the course. You can register at any time and learn more here!
What product is your go-to fuel for race day?
Do you use gels or hate them?
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