I'm a long distance runner thats not really a fan of all the goo type products.
I'm curious if there are any natural sources of concentrated sugars with the right balance of electrolytes for long distance running? I know that fruits are the most obvious natural sources for these nutrients, but which fruits? Is there a specific mix of fruits? Dried fruits? Should salt be added? Is the high fiber a concern (don't want to have to go to the bathroom during a race)?
You don't want to overdo electrolytes, so if you're going to get them from fruits or vegetables, don't add much of anything. An avocado is a great example to get potassium. Also, bananas are great as well. Presumably unprocessed banana chips (dehydrated banana) would be a good start. Celery is also a good way to up your sodium levels. All of your electrolytes can be gotten from purely natural sources, and your body will absorb them slightly easier from these natural sources.
The basic thing to remember is what your electrolytes are: sodium chloride, potassium, magnesium, and calcium. Potatoes, avocados, and bananas are good for potassium, leafy green vegetables like lettuce and cabbage for magnesium, cheese and yogurt for calcium, and celery for sodium chloride. Just plain table salt will also work for sodium chloride.
High fiber isn't a big concern. Fiber is regulatory, not diuretic. As long as you're going normally to start with, then having the extra fiber won't cause you to need to go in the middle. The big thing is the amount you'll need to consume to balance your electrolytes may actually cause you to need to go, so I would start switching over to the natural stuff slowly to see how you perform.
Example: 1oz of cheese on a few leaves of lettuce, 1/4 - 1/2 of an avocado, and a celery stalk for a "salad". That will add a load of electrolytes, but only be about 1 - 1 1/2 cups of food. Start that during practice so that if you do have to stop to go, you can get the timing down to where you can eat it long enough before you begin that you'll need to go before your run.
Gels can be problematic; if you don't get enough water with them, you end up with too high of a concentration of sugar in your digestive system, and it doesn't absorb well enough. This can lead to issues. Any source that is highly concentrated will have this issue.
Some natural sources are higher in fructose. Whether this is an issue depends on your body; some people are fine with it, others have issues.
Another option is to go more towards starchy food, which can provide the same amount of carbohydrate.
Electrolytes are a complicated issue. You want them for two reasons; they improve the rate at which liquid is absorbed, and they replace the electrolytes that you are sweating out. Whether you need either of these depends on how hard you working, how hot it is, how much time you have worked out in the heat, and how long you are going to be exercising.
