Home > Health & Nutrition

Tummy troubles on race day? A low-FODMAP diet may be the answer

Changing up your nutrition in the days leading up to your race could help you avoid the mid-race porta-potty

FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides and polyols. These short-chain carbohydrates are known to trigger gastrointestinal distress, particularly for people who suffer from irritable bowel syndrome (IBS). Individuals with IBS can adopt the low-FODMAP diet to help manage symptoms, but recent research suggests they’re not the only ones who can benefit from this way of eating. Endurance athletes, particularly runners, can also use the low-FODMAP diet in the days leading up to competition to avoid tummy trouble on race day.

RELATED: What to do when things go wrong on race day

Studies suggest that up to 70 per cent of endurance athletes struggle with exercise-related GI problems. A recent research paper published in February 2021 looked at four separate studies analyzing a number of different diets, which included the low-FODMAP diet. The aim was to investigate the impact of these diets on the endurance performance and health aspects of endurance athletes. All four studies showed that athletes who followed a low-FODMAP diet one day before an exertion heat stress trial had less GI trouble on the day of the trial.

Foods to avoid on a low-FODMAP diet

FODMAPs are short-chain carbohydrates, sugars and sugar alcohols that are poorly absorbed by the body. It’s important to note that these foods are not bad for you, and in fact, many of them are very healthy. Foods to avoid include vegetables like onions, garlic, cabbage, broccoli, Brussels sprouts, mushrooms, beets and asparagus, stone fruits (such as peaches and cherries), dried fruits and fruit juices, beans and lentils, wheat and rye, foods that contain lactose, some nuts, sweeteners like honey and maple syrup and artificial sweeteners like sorbitol or xylitol. A full list of things to avoid can be found here.

There are still plenty of foods available to you on the low-FODMAP diet, including vegetables like cucumber, carrots, zucchini and potatoes, fruits like bananas, blueberries and strawberries, lactose-free cheeses, meat and eggs, rice, oats and quinoa, non-dairy milk alternatives and some nuts and seeds. A full list of foods to eat can be found here.

A short-term fix

Unless you have IBS (in which case, you should speak with a dietitian and doctor to develop a nutrition plan), the low-FODMAP diet should only be followed for a short period of time. For runners, it can be employed safely for a few days leading up to an important race. Because several high-FODMAP foods contain prebiotics, which are good for the health of your gut, this type of diet should not be used over the long term.

RELATED: A template pre-race nutrition plan

As always, be sure to do your research before making any changes to your nutrition plan. The low-FODMAP diet is somewhat complicated, so if you’re unsure, talk to a dietitian who can help you understand it better to use it more effectively.

Check out the latest buyer's guide:

The best trainers in Canada under $150

We curated the best performance trainers under $150 to meet your 2024 running goals, while staying on budget