Coconut is a wonderful base for a real food sports drink. It naturally contains potassium, vitamins, enzymes and amino acids, so does not necessitate adding additional electrolytes beyond sea salt. Here's more information about the benefits of coconut water, plus how to ferment it.
As canned coconut milk sits on your shelf, it often separates into thick cream (on the top) and a lighter, thin, watery-looking milk on the bottom.
If you don't have time to make your own sports drinks, you can always buy containers of pure young coconut water at health food stores and store it in your pantry for an emergency. Pour this into a quart-size container (acting as the coconut milk AND the water in my above recipe), and simply add the salt, honey and lemon/lime. Find brand recommendations and buying guide for coconut water here.
Another option is to have powdered coconut water on hand, hydrate as per the directions, then add the other ingredients listed here. If you're really pinched for time, a container of pure young coconut water all by itself is still much healthier than many traditional sports drinks sold at the store.
Coconut Lemon/Lime Sports Drink https://traditionalcookingschool.com/food-preparation/recipes/real-food-sports-nutrition-part-2-hydration/