I have recently taken up running as a something to do for fun and cardio workouts. I have also been occasionally running in 5k races. Some friends of mine recommended that I consume a GU gel, which consists of complex carbohydrates, sugar and caffeine, about 15 minutes before the race starts. They say the caffeine allows for efficient muscle performance during the race.
In my last race, I didn't have any GU gel with me. So, I drank 8 ounces of coca-cola (regular, not diet) about 15 minutes before the race started. My performance was good. But since I am a beginner and starting from a slow running base, I think it's expected that I am going to see improvement in my running time.
I admit that when I finished the race, I could sense the carbonation in the coca-cola. Not a great feeling, really.
So, what do you think?
Am I going to advise you to take up the drinking of coffee and coke to enhance your performance? Of course not.
The sugar in the coke gave you some readily available simple carbs and the caffeine does have the effect of making fatty acids more readily available for utilization PLUS you had the nervous energy from the caffeine alone. Caffeine has been shown to boost mental clarity and athletic performance, but not to the point of make-or-break your win. Perhaps by psyhcological edge.
I'd suggest doing more research on this to see what matches your own needs. There's lot available on the web, yet you need to discriminate and sort out that which is just circulated by fitness professionals (as opposed to experts) who are repeating what they've heard elsewhere or who have a caffeine pill or product to sell