Marathon training: How nutrition can help performance

Training for a marathon can be really hard. Bupa sports dietitian, Nick Green, has some tips on nutrition that can help us race across that finish line.

Diet is often an afterthought to all the physical, mental, and logistical concerns a runner faces when training for a marathon—but it can be crucial to success.

“When you’re getting into running, or any form of exercise for that matter, diet is probably not a focus,” Green explains. “But your ability and your training can only take you so far. Nutrition can really help make a difference. It can be the key to better performance.”

Whether you’re a marathon newbie or an experienced runner looking for a personal best, Green’s tips can help us all get the best out of our marathon run.

Pre-marathon training: re-friend the carbohydrates

Many of us take up running to get fit and lose some weight. Often we combine our physical activity with watching our calorie intake, and in recent years, the trend for reducing the amount of carbohydrates we eat. But Green warns that cutting down carbs when you’re training for a marathon can have a harmful impact on your performance, recovery and most importantly—your enjoyment.

“If your body is not getting enough carbohydrates, your glycogen fuel stores are depleted, meaning your body has to rely on breaking down fat.”

A good thing, right? No. It seems not.

“This can lead to you feeling flat during your workouts, meaning you’ll enjoy them less and may contribute to you giving up. And if you’re not having those carbohydrates after your workouts, you’re not recovering well, not replenishing your muscle fuel stores of glycogen.”

A balanced diet that includes a range of runner-friendly carbohydrates such as whole grains, dairy, legumes, fresh fruit and plenty of vegetables is key. So is timing.

“Think about when you need to fuel, and when you don’t need to fuel. On non-training days, you don’t need to worry about the carbs so much. But on a training day, the last significant meal before you run should definitely include some extra carbohydrates.”

Baked beans on toast

The marathon: fuel, hydrate, repeat

There’s an old runner’s adage, ‘Nothing new on race day’ and it’s usually applied to all things clothing. But Green recommends this be taken a little further:

“Nothing new on race day [can] apply to food as well.”

Try not to get swept up in the whole ‘carb loading’ frenzy that tends to occur prior to a marathon. If you don’t usually eat a huge bowl of pasta the night before a long run, you probably shouldn’t eat one the night before your marathon.

“Carb loading isn’t a pasta meal the night before. It’s more about what you eat for the day and the week before. And be careful not to add too much fibre in with those carbs. Your body may struggle to deal with that amount of extra fibre on race day. You may feel unwell,” Green explains.

Anyone who’s had to run to the toilet during a race can attest to this!

And speaking of race day, the same applies to breakfast before the race, and drinks and food consumed during the race.

Green suggests a light breakfast such as beans on toast or some fruit and low fat yoghurt, or even just a banana, and recommends sipping water regularly until the start time. As for during the race:

“You should be taking on some form of carbohydrates during any event lasting longer than 90 minutes; a sports gel, sports drink or even a banana if you can carry it. The recommendation for carbohydrate intake is 30 to 60 grams per hour. And don’t wait until you’re feeling fatigued or dehydrated. Start re-fuelling and re-hydrating 30 to 45 minutes into the event just to keep on top of it.”

It may help you avoid running into that runner’s dread—‘the wall’—towards the end of the marathon. And if you can, bring your own snacks. Don’t rely on what’s available at the race.

“If you count on a gel at the 18 kilometre mark, because that’s what race organisers have told you will be available, but then arrive to find they’ve run out or you can’t get to the station and keep on going past, you [may have] completely messed up your race plan,” Green warns.

Practice your fuel and hydration strategy during your long training runs and then, when race day comes along, repeat. This could be the difference between having a very average (hopefully not disastrous!) marathon experience and an exceptional one.

Post-marathon recovery: the big three

At the end of a marathon, I think any runner would be forgiven for falling into a post-race blob of exhaustion, followed perhaps by a feast of epic proportions with little regard to nutrition. But as Green explains, this is when nutrition counts most.

“There are three things you’re trying to achieve. You’re trying to refuel with carbohydrates, trying to repair with protein, and trying to rehydrate with fluid, ideally within the first 60 minutes of the activity having finished.”

A meal that includes some rice or potatoes for carbohydrates and some steak, chicken or fish for protein washed down with plenty of water is ideal. If you’re not heading for a meal, some key snacks such as nuts, bananas and a smoothie should tide you over.

While many runners focus on protein and rehydration for recovery, we often forget about the carbohydrates. But all three are just as important as each other, Green explains.

“Without carbohydrates, your post-exercise recovery will prove more difficult and be less-effective, meaning you [may be] less likely to achieve your future goals.”

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