By the time you are experiencing an acute electrolyte imbalance the time is generally passed for a quick fix, and you are well into heat exhaustion and dehydration. Anyone who has experienced beat exhaustion can tell you this - it can take hours of sitting down and sipping fluids or even IVs to properly recover.

You will generally get enough electrolytes even for rigorous outdoor activity just by eating three normal meals. The exception to this is if you will be doing high intensity workouts for long enough that it requires skipping a meal, then replacing the meal with glucose and salt supplements can keep you from fading or "bonking" as cyclists call it. But even then the conventional cycling wisdom that you need to do this for any ride over 30 minutes is silly, and likely influenced by doping regimes which deplete athletes much faster than normal.