Fuelling for training is vital for optimal performance. Carbohydrate is the main fuel for training as well as racing. The body is only able to store a relatively small amount of carbohydrate which is why keeping it topped up is so important.

How long after eating a meal should you wait before going for a run depends on your level of comfort regarding eating so it is important to try what works best for you.

In general, allow between two and four hours before running after eating a meal to allow time for food to fully digest.

After a smaller snack, 30 minutes should be sufficient.

Should you eat before an early morning run?

You should eat where possible before your early day run, especially if it’s over one hour in duration. Many athletes find this difficult but it is important to ‘train your gut’ for the big day, especially on longer runs.

There are two morning situations to plan for.

The early riser: If you wake up two hours before your run, good options include oats, wholegrain toast topped with eggs, granola, bagels or breakfast muffins and freshly made smoothies.

Straight out of bed: If you prefer to get straight on the road with minimal fuss, try a small snack with quick releasing energy such as dried or fresh fruit, nuts and seeds or a shake.

If you are really struggling to eat first thing, try increasing the carbohydrate portion of your evening meal the night before, as this will be stored in the muscles ready for your morning run.

To provide sufficient fuel, foods should be predominantly high in carbohydrate but you should also eat foods that you’re used to, make you feel comfortable and don’t feel too ‘heavy’ in your stomach.

In the two-four hours before a run, try to limit those foods that could cause gastro-intestinal distresses, foods very high in fibre, excessively fatty or unusually spicy meals and also drinking too much caffeine and alcohol.

What you eat on the morning of your event should link into an overall fuelling strategy that you have developed during training.

Keeping your energy up and establishing a solid fuelling strategy for long runs can be tricky.

Eating during a run can be a new experience for many, and can feel slightly uncomfortable to start with. It is vital to trial eating strategies during longer training runs as this will help train the body to digest carbo-hydrates while on the move.

For training runs under one hour there is no need to refuel on the move but for longer runs you should practice taking on small amounts of high-GI carbohydrates.

They will help top up blood glucose and provide ongoing fuel to the working muscles to help maintain a good pace of running.

Sticking to easily absorbed, high-GI carbohydrate options should help you avoid discomfort and nausea during a run. Where possible, try to include some carbo-electrolyte sports drinks to meet your fuel and fluid needs.

Eating when feeling hungry or snacking continually during a race depends on your body adapting to a strategy that is comfortable with.

Don’t rely on hunger as a cue to refuel during the race. As a general rule, practise 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 way.

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.

And, finally, how to recover after a run.

If you’re training hard for an endurance race, getting your recovery right is vital.

Ideally one starts to eat the sooner the better after a run to maximise recovery. It is advised to eat within 30 minutes after running as your body needs essential nutrients to kickstart the growth and repair process after a hard training session.

Ideally, one should include both carbs and proteins in an intake after a run.

On a final note, how long after running a marathon would it be sensible to start training again?

It is important to listen to your body on this one. You can be ready to start training after a few days, especially as fitness levels often improve with endurance training.

However, don’t underestimate the fatigue you may experience over the following week. It is usually advisable for runners to have a break of a week to get a well-earned break from running before lacing up the trainers again.