Training and racing with a happy tummy

GI (gastrointestinal) problems are very common in athletes, specifically endurance athletes. It is known that the prevalence for GI distress is amplified as racing duration continues, especially in hot environmental conditions.

GI concerns relating to sport nutrition
Although gas and burping may be bothersome during racing, they are typically not performance limiting. However, heartburn, painful side stiches, diarrhea/bloody stools, vomiting and uncomfortable bloating/swelling can be extremely health threatening and performance debilitating. 

When it comes to race day, PR or ER is not the mentally you want to have if you race without fine-tuning your race day sport nutrition.

Predisposition of GI issues is common, relating to genetics, biomechanics, anatomy, age, diet and health. Some athletes can experience GI issues simply from a poor bike fit or running posture. Let’s look at some other reasons why your tummy may not be happy during racing:

- Your body may not be well-adapted to tolerating fluid/calorie ingestion during training and/or your fueling timing may be off.  Don’t let race day be the only day you use sport nutrition products (or new products). Use the same nutrition products (and pre training snack/meal)  for at least 4 weeks (preferably longer) to improved intestinal absorption and tolerance of calories, fluids and electrolytes. It's very important to not slack on adequate carbohydrates AND water AND electrolytes during every workout. Don't just "get by" and underfuel and underhydrate in order to check-off a workout and then try to be "perfect" on race day. You must train your gut and avoid serious issues in training like dehydration and glycogen depletion.

- Well-formulated sport drinks are simple to digest and are designed to meet carbohydrate, electrolyte and fluid needs. Don’t be a nutrition chemist in your kitchen and create your own concoction or overconcentrate your bottles. Most sport drinks will meet your hourly carb, electrolyte and fluid needs and they are easy to use! It's important that you select the product that is best for you (with the least amount of ingredients to digest/absorb) and tastes the best. Just make sure you drink adequate fluids to combine with the powder throughout all of your long workouts and on race day.

- Your racing intensity is too high or you swallow too much air or water in the swim. Sorry epic bikers, but you need to slow down in order to avoid suffering on the run. The energy (calories) you consume during training/racing is only effective if it is emptied from the stomach and can be quickly absorbed through the walls of the small intestine. For maximal digestion and absorption, train your gut on the bike with liquid sport drinks of  ~4-8% carbohydrate solution mixed in 20-28 ounces of water with at least 200 mg sodium (and other electrolytes) per 8 ounces each hour and same on the run. Consume frequently (every 8-15 minutes). Cycling and running fueling requirements will differ.
In the case of an upset tummy due to swallowing water or air during the swim or just feeling off, take a TUMS when you first experience an uncomfortable gut feeling to relieve the pressure immediately. Afterward, it's up to you to slow down and try to relieve or further prevent the problem from happening again. 

-You consume sugar alcohols/sweeteners in the diet or too many gas-producing foods. I highly recommend a low residue-diet in the 48 hours before a race so that you can reduce the amount of stool that you produce as well as easing the stress on the gut. 

Low residue friendly foods: 
Refined grains (white rice), cooked cereals (ex. cream of wheat, grits), corn/rice based cereals, cooked veggies (no seeds), cooked potatoes, ripe bananas, cooked fruits, applesauce/fruit blends, lactose-free milk products, lean meat, rice cakes, honey, syrup, pulp-free juice.

- GI symptoms are highly individualized and often circumstantial. Weather, nerves, diet, health status, terrain, racing intensity and duration affects digestion and absorption. The hotter the race, the more likely the risk of GI issues due to dehydration and pacing issues. 

-A pre-race bowel movement can be welcomed before a long workout or on race day morning.  However, increased bowel movements during a race are never well-desired.

Research shows that excessive consumption of fiber, fat, protein, sugar alcohols, additives, sweeteners and fructose are all associated with a greater risk of GI issues during race day.
Although adequate fiber in the daily diet will help keep you regular during training, a low residue diet is recommended on the 2-3 days before the race (residue refers to undigested foods that make up stool).

For a happy tummy on race day, it’s up to you to figure out how much carbohydrates, electrolytes and fluids you can consume to prevent bonking and dehydration but not too much that it will negatively affect your gut. Because the most successful endurance athletes are those who slow down the least, it’s not just about preventing GI-related issues on race day but knowing how to deal with them when they come about. 

Because blood flow to the GI tract is impaired during exercise, dehydration can often exacerbate GI symptoms due to slow gastric emptying. Pre- race/workout hydration is just as important as race day hydration. Consume at least 2.7L/day of water (women) and 3.7L/day (men), in addition to any electrolyte tablets, electrolyte powders and sport drinks that are needed on race week to support your upcoming fluid, electrolyte and carbohydrate needs.
Do not overconsume fluids on race day morning. No more than 30 ounce fluid is needed in the 3 hours before your race so that you can well-hydrate without experiencing excessive urination.