Carbs are King/Queen

In endurance sport, including ultra marathon running, carbs are king/queen. Carbs are our primary fuel source and the one that allows us to perform at our best. Yes we are always burning some percentage of our calories from fat, but maintaining optimal levels of blood glucose through the regular consumption of carbs during endurance running is the only way to perform at our best. 

Carbs are king/queen throughout the day

Let's talk about how to flourish in a carb world. First we want to eat a relatively high carb (CHO) diet to prevent low energy availability (LEA), relative energy deficiency in sport (REDs), and low carbohydrate availably (LCA) which all have negative health and performance outcomes (read more about this here) and  keep our muscle glycogen stores topped up. Daily CHO needs for an ultra-runner are 6-12g/kg body weight. The lower end for athletes running an average of an hour a day and the higher end for athletes averaging 4+ hours of running a day. 

We want to make sure we spread our CHO consumption out throughout the day so we don't spend hours in low carbohydrate availability. This means carbs with breakfast, lunch, dinner, and snacks between meals (which all of us ultra runners should be having). 

Carbs are king/queen during exercise

During endurance exercise, especially over 90 minutes, we should be consuming CHO. How much CHO should we consume during exercise? The American College of Sports Medicine position stand is to consume 60g CHO/hour for exercise lasting 1-2.5 hours and 90g CHO/hour for exercise lasting longer than 2.5 hours. Research has shown that consuming more CHO (up to 120g CHO/hour) can be even more beneficial in terms of performance, reduced ratings of perceived exertion, improved mental state, decreased post-exercise muscle damage (DOMS), and improved recovery. 

Multiple transport carbohydrates are the most efficient way to consume and absorb CHO which means consuming a mix of glucose and fructose. You can read more about this in my article about Race Day Nutrition.

Cyclists have been pushing higher and higher CHO intakes during training and racing and have seen performances increase. Ultra runners are following suit and experimenting with higher CHO consumption during training and racing. Over the years, I've gone from consuming 60g CHO/hour to 75g CHO/hour to 90g CHO/hour to 120g CHO/hour and not only felt better in training and racing but performed better and all without gastrointestinal (GI) distress. 

If you have not experimented with higher CHO intakes during longer training runs and races, I highly recommend it. The gut is highly trainable, and fairly quickly, but it does take practice. 

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