Higher carbohydrate intake is associated with improved endurance performance but it’s not always comfortable to take in 60-90 grams (or more!) per hour when you haven’t practiced it. If you have a hard time taking in the recommended amount of hourly carbohydrate intake, you aren’t alone! The most common reasons for not reaching the recommendations seem to be:
- GI issues
- Too full
- Carrying that much fluid/food for several hours
- Low appetite and feeling like you’re “forcing” nutrition intake
- More carbs doesn’t seem necessary if you feel like you are performing well with less
In this post I want to address one of the most common complaints: GI issues. But, GI symptoms don’t have to be a regular occurrence if you work on TRAINING THE GUT...Yes! The gut is trainable just like the rest of your body. If you are barely able to reach the 60 g CHO/h intake recommendation then it’s not likely that you will be able to easily go out and throw back 90 g CHO/h without issues. That’s why we need to be deliberate in how we train our body’s ability to digest, absorb, and utilize that amount of hourly carb intake.
One of the best ways to adapt our GI system to a higher carbohydrate intake during exercise is to eat more carbohydrates in your regular diet. Repeated exposure to carbohydrates, including glucose and fructose, can speed up gastric emptying rates of these monosaccharides and increase the transporter activity to facilitate better absorption and oxidation of the carbohydrate. Benefits may include decreased feelings of “fullness”, less GI distress, and better overall performance. There are several other things you can implement when “training the gut”:
1) Start euhydrated (consume ~2-4 ml/lb fluid with sodium 2-4 h prior to establish euhydration)
2) Hydrate with ~ 400-800 ml/h using fluid with sodium (adjust as needed based on environmental conditions)
3) Gradually increase the hourly rate of carbohydrate intake
4) Practice ingesting carbs during different types of workouts (intermittent high intensity intervals and steady state, short and long duration)
5) Train shortly after a meal
6) Decrease fat/fiber/protein leading in the meal(s) prior to the training session
7) Practice your race nutrition strategy in different conditions well in advance of your goal event
PMID: 28332114, 26891166
