Consuming too much fiber.
Eating too many foods full of fiber can lead to all of what you have consumed building up in your colon and causing GI distress on race day. For this reason, we often recommend to limit foods like beans and steel cut oats the day before the event.
Eating a carb dense meal late at night.
Carb loading is a great way to optimize your performance on race day, but this does not mean eating a big carb heavy meal the night before. Instead, you want to consume the majority of your carbs earlier in the day before your race so that your GI system has enough time to digest the food. This will also help you load those carbs into your muscle tissue as glycogen that your body will then use as fuel for race day.
Consuming too many fats.
Another mistake some athletes are making is assuming that they can include a bag of chips or pizza as a part of their carb load. While we prefer to have a neutral perspective on food, these types of “carb sources” that are also high in fat content are not ideal 1 day before your race. Chips, pizza, and even pasta with high fat content will actually slow your gastric emptying rate and thereby contribute to GI issues on race day. Additionally, fats are a very satiating macro, so if you feel more full from eating 1 bag of chips, it might make it harder for you to eat enough carbs to hit your carb loading target.
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