Long-distance runners: Food to fuel your training

Don’t load up on carbs or down litres of water the night before a long run

Food is never far from the mind of a runner training for the marathon. Whether it is the pre-run breakfast, mid-run snack or post-run recovery lunch, thoughts are always on the next meal. But with an array of nutritional products, extensive marketing and plenty written on the subject, it can be a daunting task for a first-time marathoner to weed through the sales pitches and work out what food or sports supplements are right for their body in training.

A personalised menu

There is no perfect diet for a marathoner. Having trained runners to take on the marathon for more than 12 years, no two runners have made the exact same food choices. Everyone has different preferences, schedules and sensitivities. Anyone who has already been on the marathon journey has learned, possibly the hard way, what foods agree with their body.

But for a first-timer, the only real way to work out what to eat is to experiment each week in training. Eating on the run can be a challenge for many, as can the digestion of a pre-run breakfast, but it’s important to remember that it’s not just the long runs days where what we eat matters.

Get the basics right

Very simply, the food you eat day-to-day when training for a marathon will supply the energy and nourishment for your running and help support your recovery. A sensible balanced diet all week long with plenty of fruit and vegetables and good sources of protein will be a great start for any marathon runner.


Some runners only think about food when it is getting close to their weekend long run but please try to steer away from this last-minute cramming. There is no point loading up on carbohydrates or downing litres of water the night before your long run. You will only have to carry them around with you on the run. Instead, spread the load across the week.

The meals before the marathon

Our weekend long run replicates our marathon day in terms of effort, endurance and fuelling. If we can perfect what meals agree with us before we run, we can head into the marathon with one less worry on our mind. Avoid eating too late the night before your long run and keep away heavy or spicy food. Choose something you actually enjoy eating, as you should stick with that very meal before each long run between now and the big day. Play around with breakfast ideas too and the gap in time between eating and running. Your usual breakfast might be just fine or you might like to try popular options such as bananas, bagels or porridge. Try not to overeat as you will just have to carry the food around in your stomach. Easy on the morning fluids too as you will only be looking for the toilet en route if you drink too much too close to running.

Eating on the run

When we run we lose salt, sugar and water. How you replenish these is up to you. If you don’t fancy meeting that dreaded marathon wall, you really need to keep an eye on fuelling smartly. Some people like to choose the traditional options of fruit, biscuits and homemade snacks but there are also an array of practical and portable products on the market designed to keep your energy up.

If you are not sure where to start with your mid-run fuelling, aim to eat something small every three miles on your long run and see how that works for you. Adapt each week based on how your body reacts and soon you will feel confident in your choices. If you have never eaten before while running, start with a few jelly sweets or some dried fruit to get used to eating on the run.

What products to buy

The marathon products you may have seen in the shops such as gels and sweets do offer a mix of salts and sugars to help keep us in balance. When combined with plenty of fluids along the way they can work really well for many runners. But there is no way to know if these products are for you other than to practise each week. Just remember to read the labels. There can be many extras added to these packaged products such as caffeine.

While we all could do with a kick in the marathon, caffeine can pay havoc on the run for some runners, sending them in the direction of the nearest toilet, so be cautious in that regard. Maybe save the caffeine for the last hour of the marathon. That’s what works for me.

Keeping it natural

While generally I would steer clear of the sickly sweet products outside of endurance running, the energy gels have worked for me over the years and give me that hit I need, both physically and psychologically, to keep on going. I certainly wouldn’t fancy eating a banana that had been in my back pocket for three hours or a crumbled up biscuit that I know from experience will dry my mouth out. You need to consider not only what agrees with your stomach but also what is practical for you to carry and access on the run.

Plan for success

Consider the marathon day that lies ahead of you later this year. Will you be running virtually or do you have an organised event to attend? The joy of virtual running is that you can plan your route, leave out the snacks you need, arrange to have toilets en route and start at a time that suits your body. This flexibility gives you more freedom and fewer things to carry.

If you are running an organised event, you might get more cheerleaders on the sidelines, but you need to plan what to bring with you and where along the route you will eat. Get familiar with where the food/water stations with be and what food and drink choices they will have on offer.

One week at a time

You won’t be able to visualise the full marathon day in detail right now, but as the weeks go on it will become clearer and your confidence will build. By the time you start tapering you will have a much clearer picture of your marathon menu and the timings of eating. But for now, just take it all one week at a time and it will all come together in the end.

Mary Jennings is founder and running coach with ForgetTheGym.ie. Her autumn term of running programmes and classes start September 6th