''Eating during a run can be a new experience for many, and can feel slightly uncomfortable to start with'' says James. ''It's vital to trial eating strategies during longer training runs as this will help train the gut to digest carbohydrates while on the move.''
How far or how long can I run without refuelling?
For training runs under one hour there is no need to refuel on the move as long as you have eaten enough to keep your energy up before setting out. For runs over one hour in duration, individuals should practice taking on small amounts of high-GI carbohydrates, which will help top up blood glucose and provide ongoing fuel to the working muscles to help maintain a good pace of running.
These easily absorbed carbohydrates also provide important fuel for the brain, which allows the body to keep working harder, especially when muscles begin to tire. Interestingly research has indicated that using a carbohydrate sports drink as a mouth rinse may help to activate the brain - which could be a useful technique later in the race if you struggle to take on fluids.
What are the best foods to eat on a run to avoid feeling full?
Sticking to easily absorbed, high-GI carbohydrate options should help you avoid discomfort and nausea during a run. Where possible, try to include some carbohydrate-electrolyte sports drinks to meet your fuel and fluid needs.
What are some different options for energy-boosting during a run?
If you already regularly consume caffeine as part of your diet, this can be a usual alternative to carbohydrates for an energy boost. There are commercially available sports drinks and gels containing caffeine, which can be extremely useful, especially later in the race.
Should I only eat when I feel hungry or should I snack continually during a race?
Don't rely on hunger as a cue to refuel during the race. As a general rule, practice and refine your fuelling during training and find a strategy you're comfortable with. Taking on carbohydrate little and often, for a constant energy supply, is often the most efficient strategy.
As a rough guide, approximately 30-60g of carbohydrate an hour will be your target during the marathon, as the body can absorb this amount and use it for energy on the move. Carbohydrate drinks are typically the most efficient way to meet these targets, alongside good hydration. Carbohydrate gels will also be readily available on race day and are rapidly absorbed. Small pieces of banana, cereal bars and jellied sweets also can help to offset hunger.
The following will provide around 30g of carbohydrate - see what works best for you and experiment with quantities during training:
• 500ml bottle of commercially available sports drink
• One and a half carbohydrate energy gels
• A small handful of jellied sweets
• One large banana
• One large cereal bar or carbohydrate based energy bar (choose a low-fibre option)