Avoid Extra Calories
Too many calories during training or racing can prevent you from reaching the finish line. If you consume more calories than you can digest during exercise, those carbohydrates will linger in your digestive tract and actually inhibit the absorption of fluids. Not only will you not get the calories, but it will slow your rehydration efforts.
Many endurance athletes report this experience as feeling bloated and uninterested or unable to eat or drink. Worse than feeling bloated, this can also be the cause of severe stomach upset or other forms of GI distress.
Hydrate With Electrolytes; Refuel With Calories
A hydration strategy that separates rehydration and calories can eliminate the risks of over or under consuming.
1. Replenish electrolytes with your hydration.
There are several brands of dissolvable electrolyte tabs on the market that provide balanced electrolytes with under 10 calories each. Some examples include nuun, Zym and Hammer Endurolytes FIZZ. There are also low calorie (60 per serving) energy drinks with electrolytes such as Accelerade Hydro or Enervit G Sport.
2. Get your calories from a separate source.
There are a wide variety of sources for getting the calories you need to fuel your endurance. These can be gels, bars, chews, or a variety of foods. If you prefer getting your calories from a liquid, then there is no problem mixing up a bottle of your favorite energy drink. Just make sure it isn't your only source.
Many long course or ultra endurance athletes will mix a concentrated bottle of Hammer Perpetuem as a multi-hour bottle. You can do this with any sports drink. Consume your calories regardless of form (bars, gels, chews or liquid) on a regular schedule and rehydrate as you are thirsty.
Nothing New On Race Day
As always, train with what you will use on race day. You may tweak your hydration and nutrition plan based on the weather, distance or intensity, but you shouldn't radically switch strategies. If you plan on using this strategy on race day, make sure you train with it as well. As your distances increase, strongly consider sourcing your electrolytes and calories separately.
Eat right and perform better. Find a nutrition plan for you.