A popular method of achieving this is by ingesting one or more of the myriad of carb gels available, predominately wrapped in day-glo packets containing all sorts of un-pronounceable chemicals which the fantastic www.energygelcentral.com calls 'marketing fluff'. The more I read, the more confused I became as to which was the best gel and as I generally prefer the natural route to nutrition I've decided to try and make my own carb gel substitute. And it shall be known as 'Go Go Gu'!
There are several resources suggesting recipes to replicate the branded gels based on combining two or more types of carbohydrate e.g. maltodextrin, dextrose and fructose so that the body can process more carbs overall (click here for the science) plus something to make it taste nice, for example: fruit purée, lemon juice or vanilla.
These recipes are usually an economical endeavour aiming to replicate a shop-bought energy gel which can be over £1 a go (and you need several per long run). I didn't really want to shell out on sacks of sugary chemicals from the off so I narrowed my research with a more natural theme and came across this simple statement:
'Bananas are a naturally efficient and convenient food for runners to use as fuel. Their high carbohydrate content makes them good sources of energy. They're rich in potassium and magnesium, minerals that runners lose as they sweat. They also have chemical properties that help control stomach pain from nerves and reduce the risk of stomach upsets'And so the humble banana is not only the perfect running fuel but the average shop-bought energy gel has around 100 calories and an average sized banana is roughly 95 calories - uncanny!
Carrying four bananas in some bespoke ammo belt however, seems impractical and even if I could, I still haven't mastered the run-chew-breathe-at-the-same-time trick.
To overcome these issues, mushing it up seemed like the best way to make it easily ingestible and gel-like and to add interest, viscosity, a few extra calories and presumably a different carb source (glucose vs. natural fructose in the banana), I added a heaped teaspoon of Creme de Marron (chestnut spread with vanilla) that I found in France.
It tasted great!
My Go Go Gu (GGG) was initially dispensed from a small plastic container which proved tricky to use mid-run. I subsequently came across a suggestion on a mountain bike forum which advocated silicone tubes - only available in the UK from Lakeland. With them, it is possible to squeeze my GGG (Formula #1) into my mouth whilst running, not have to chew very much and wash it down with a sip of water.
As it stands, I'm happy with Formula #1 but it takes up too much volume - one small GoToob plus one medium GoToob currently delivers only one banana-dose, and as I might need 4-6 doses for the marathon I am going to experiment with dehydrating the mix by cooking gently and/or substituting some banana for nut butter and honey to increase its energy by volume.
If only I could find someone extolling the virtues of cake with tea as healthy running fuel... all I'd need would be a blender and my Camelbak :)