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Raise your hand if you’ve ever bonked on a run! Unless you’re one of the precious few who’s never made that mistake, you have learned the hard way that mid-run fueling is critical. That’s why runners training for 75 minutes or longer stuff their shorts with gel packets, their race belts with chews and their water bottles with electrolyte solution.
But have you ever considered what’s really in that little plastic pouch or tube? We enlisted the help of Kelly R. Jones, a Philadelphia-based registered dietitian and sports dietetics specialist, to help us break down the ingredient list in our fitness-friendly “snacks.” Here’s what we learned.
Nuun Active Tablets
Designed to be dissolved in water, Nuun tablets provide electrolytes and other vitamin and mineral replacement without much sugar or carbohydrates, spokesperson Becky Lynn explains. This means the tablets—when used alone—are best for short to mid-distance runs when you do not need additional energy. For longer runs, Nuun Active can be taken in conjunction with gels or chews. Drop tablets into the water you plan to use during your race or run. Use one tablet per 16 ounces of H2O.
What’s it made of?
Calcium carbonate: This is your electrolyte that packs in magnesium, sodium and potassium. Nuun Active has nearly three times the amount of sodium in Gu Energy Gels and five times the amount in Glukos Energy Gummies. There isn’t any one-size-fits-all approach to replacing electrolytes as individual sweat rates (as well as the temperature, humidity and length of exercise) differ. Jones says a person loses about 1g of sodium per liter of fluid loss. She advises not to add tablets for flavor when you don’t need them as too much sodium can impact blood pressure and bone health over the long term.
Dextrose: A carbohydrate used to help facilitate fluid and electrolyte absorption. In Nuun, it is sourced from non-GMO corn.
Monk fruit extract, stevia leaf extract: These naturally occurring extracts add sweetness with minimal calories. Stevia hits the pallet first and monk fruit second, which is why they’re used in conjunction. Some people have trouble digesting stevia so stay aware of this effect.
Beet juice powder: This provides a pink or red color.
Avocado oil: This is a lubricant during the production process.
Riboflavin: A B vitamin, which is important for energy metabolism.
Citric acid: This preserves the product from spoiling.