Hello, I have 5 years running, each body is different, I recommend you try everything in training and not during the competition. For the race itself, there are banana sandwiches easy to carry and consume, also honey bee capsules that gives you a lot of energy in competition. The same training must adapt to you, and see what works and what does not. I tell you about the drink with salt is to replace the salts that you lose when you sweat excessively, I prepare a drink with water, orange, sugar and salt, check the proportions on the internet, I have found it excellent for routes of more than 20 Km. I wish you much success and I am at your service for any concern you may have, I am not an expert, I only speak from my experience and my passion for running.