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The 3 Keys To Race Day Fueling

Don't let GI distress derail your race day experience. Here’s how to dial in your race-day fuel routine to maximize success.

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To begin nailing your race fueling, it is important to understand the mechanisms behind it so that you can cover your bases.   Many runners go directly to calories as being the cause for all of their issues, but unfortunately it is more complicated than that.  Fueling properly requires a delicate balance of three keys: fluids, electrolytes, and calories.  If one of these gets knocked out of balance by too little or too much intake (or the wrong source), disaster can ensue.

1. Get in those calories

Calories=energy.  Your body has about 1,800-2,000 calories of carbohydrates stored as glycogen in the muscles and liver (think of this as your gas tank). Once this tank is emptied, if you aren’t taking in calories from outside sources, your body is solely relying on fat and muscle for energy production.  These systems can and will be utilized for energy production, but the process will be slower, leaving you to bonk, and can lead to serious health risks, such as heartbeat irregularities and rhabdomyolysis (kidney damage).

When setting up a target calorie intake for yourself, 200-300 calories per hour is often a good, general starting point for most runners.  Smaller-framed runners may be able to start on the lower end of this recommended intake, while larger-framed runners could start on the upper end.

When considering calorie sources, carbohydrates are still king for energy production for endurance runners.  Even if your pace is slower, carbohydrates are going to provide an efficient energy source that will keep you alert and able to push hills and maintain pace.

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Aim for mostly carbohydrate rich calorie sources with a bit of protein and some fat mixed in is a good starting point.  Calorie sources for running events can come from a combination of hydration mix, whole foods, gels, and chews.  Figuring out what works best for you is where science meets art.

Some runners like the convenience of getting calories from hydration mix, while others prefer just water and electrolytes, getting their calories from whole food sources.  Gels provide a quick source of energy that may be preferred for shorter events, while some runners have stomachs that can’t handle them.  Take it from an expert: there is no one best way to fuel, and chances are the first thing you try might not be the best option. It takes time and testing to figure out what works for you.