As a dietitian, I have the ability to help clients reach their health and fitness goals through appropriate nutrition strategies. Usually, I’m thinking long-term, with foods that provide adequate fiber, protein, and complex carbs. I want your digestive system to work hard to extract the best nutrients for performance and overall health.

But on race day, it’s an entirely different story. Most of my clients understand how to eat on a daily basis, but they have a hard time breaking the rules when it comes time to compete. The truth is, some of world’s most nutritious foods could be more likely to give you digestive problems or cramps on race day. Plus, they don’t provide the high-octane energy you need for a strong finish.

Related: 12 of the Best Training-Friendly Nutrition Tips, According to Experts

To perform your best, you should ditch the focus on strict nutrition for a focus on fuel. They’re two completely different animals. So, here are four strategies to help you hit your next PR on the race course.

Nutritional Rules You Can Break When Fueling Up on Race Day

1. Stop Eating Vegetables

Day to day, you should be pounding plant matter. The phytonutrients and fiber help maintain regularity, aid in cancer prevention, and provide a huge bulk of your daily vitamins and minerals. But they also linger in your gut for a long time, weighing you down when you need to feel light on your feet.

By eliminating vegetable intake during the 24 hours prior to your race, you will allow your body to fully process these high-fiber friends and send them on their way, leaving your intestinal tract free and clear. This approach helps reduce race day stomach upset that could hinder your speed.

Related: This Is How Leaky Gut Syndrome Directly Affects Your Workouts

2. Ditch the Whole Grains

Again, you should be eating as many high-fiber foods as possible every day. But skip them entirely for the 24 hours preceding a race. As with vegetables, whole grains — those with the tough bran still intact — will break down slowly and take time for the body to process. Additionally, some of that fiber will remain in the intestinal tract, possibly causing discomfort on race day.

So leading up to a competition, swap out whole grains for white bread or pasta. These low-fiber, easily digested sources will assist in topping off your muscles’ glycogen stores while moving swiftly through your gastrointestinal (GI) tract. But remember: Once the race is over, it’s back to whole grains.

3. Don't Be Shy on the Salt

Generally, you should keep your sodium intake below the government’s recommendation of 2,300 milligrams per day. But when you’re training for or competing in an obstacle course race or Trail race, an extra hit of salt and other electrolytes can keep your muscles operating smoothly.

The best time to think about cramps is not during the race, but in the days leading up to it (especially if you’ve been hydrating properly). Extra water during the week leading up to the race can throw off your electrolyte balance, which can impair the function of your muscles, heart, and nerves.

Related: 4 Reasons Your Muscles Cramp Up (and What to Do About It)

In general, Spartans should aim to take in half of their body weight in ounces of fluid (primarily water) per day. So, a 150-pound person should have 75 ounces. During the week leading up to the race, replace a percentage of your water intake with an electrolyte fluid source. Your most beneficial electrolyte source will provide not only sodium, but also potassium, magnesium, and calcium.

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4. Cave to Your Cravings

Our bodies are brilliant. They are very aware of what they need at any given time and they are constantly on the lookout to make you aware of depletion. The above recommendations? They’re just guiding principles.

So listen to your cravings. Do you feel an urge to devour a bowl of ice cream? Your body may be sending you signals that your glucose levels are low. In the mood for savory? Perhaps your electrolyte balance is off or you haven’t eaten enough healthy fats.

Related: Eat This One Food to Avoid Mid-Workout Gut Rot

Listen to your body and eat foods that you enjoy that you know you digest well. Go into a race feeling satisfied and ready. That said, always remember the cardinal rule: Never try new approaches on race day. Stick with foods that you tested during training, and that you know won’t slow you down.