One of the more appealing aspects of marathon training for many people is the promise of limitless guilt-free carb consumption, especially in the days leading up to the event. However, fuelling correctly for your race requires more than just shovelling down platefuls of pasta the day before – though we can promise platefuls of pasta are on the agenda at times.
For an expert take on what to eat before a marathon we spoke to David Dunne, a performance nutritionist and the co-founder of Hexis, a training platform that can create a tailored nutrition plan to fit with your training and help you perform at your best.
How long before a marathon should you start considering your meals?
Everyone tends to dial in their nutrition in the seven days before, but most people who are training for a marathon start 12 to 16 weeks out. My advice is that, if you are starting to train for a marathon, the best thing you can do is to begin to align your nutrition to complement your training from the get-go. You’re going to follow a periodised training programme, in that you’re going to run longer some days, slower on others and faster and shorter on other days. I’d be periodising nutrition in line with that from the time I commenced training.
As you get to the event, you should be looking at directly influencing your fuel availability for that marathon: how much carbohydrate you have stored in your muscle and in your liver as glycogen. You’re looking at the 24 to 36 hours before the race.
What is carb-loading and why do people do it?
We store carbohydrates in our muscles and our livers. Our muscles tend to have the biggest amount and we store that as glycogen. We break down glycogen into glucose to help fuel our exercise. If we run out of glycogen early it can cause us to fatigue early and limit performance. We carbohydrate load to increase the time to fatigue and ensure we have sufficient fuel to be able to complete the work. So you should carb-load in the 24 to 36 hours before a marathon.
What kind of food should you eat in that pre-event period?
In the day or two before a marathon we don’t need a huge amount of fibre in our diets. Fibre can cause us to feel full, so I’d reduce the fibre intake to make it easier to consume higher volumes of carbohydrates. Look at carbohydrates that are simple to consume in large amounts – things like basmati rice, white pasta. Higher glycaemic index (GI) carbohydrates can be effective at topping up glycogen stores. I’d be prioritising snacks that are easier to consume as well. Things like fruit juice and a bag of popcorn. You could get 90g-100g of carbohydrate while you’re sitting watching Netflix, and effectively top up that fuel store for the next day.
Should you spread the carbs out between meals?
Definitely. The day before the race I’d make breakfast a higher-carbohydrate meal. That could be something like pancakes with a little Greek yogurt, banana, honey and fresh berries.
As you progress through the morning, if you are going to have a snack you could have a fruit smoothie, but with a fruit juice base to try to increase the overall carbohydrate content, instead of a milk base where you might be looking to increase someone’s protein intake. Lunch and dinner could be a pasta, rice or noodle dish: a stir-fry with a high-sugar sauce, such as teriyaki, or it could be a platter of sushi. That’s a tasty and effective way to get a decent amount of carbohydrates.
Don’t go crazy on the vegetable content – just have some for flavour. Generally, for pasta go for a tomato-based sauce over a cream sauce. Asian food tends to be flavoured with spices and soy sauce, and those dishes are great as they can be lighter so it’s easier to consume bigger portions.
When should you eat breakfast on the morning of the marathon?
The majority of fuelling is going to be done the day before. So, if you haven’t effectively topped up your fuel sources the day before you’re not going to be able to make up that deficit with a stellar breakfast.
On the day, depending on what the start time is, I’d say have your last big meal three to four hours before the event. If you start early it may have to be two hours before. Then, in the 30 minutes to four hours before the event, you may look at having an additional snack to top up, like a banana or energy bar.
Working out what your individual preferences are is important. If you go out for a long run on a Sunday morning, it’s always a good chance to practise your race day breakfast. I’d pick maybe one session every week during that 12 to 16 weeks of training and treat it like a race scenario. Refine what feels good to eat for dinner the day before and for breakfast. What sits well, what’s a good portion size for your gut to get used to. Don’t wait until race day to try your plan.
What are some good race day breakfasts?
You want something that is predominantly carbohydrate-based. A large bowl of porridge topped with additional high-carb fruit like banana or dried fruit, maybe some honey. Or try a Bircher muesli. If not that, then scrambled eggs with bagels and jam; peanut butter can be added for more flavour. However, err more on the carb side than the fat side. Make sure you’re hydrated as well. For most people [that means] consuming five to 10ml per kg of their bodyweight. If I’m 80kg that’s 400ml-800ml of fluid one to two hours before the event.
Are high-energy sports products worth using before the race?
There are good products out there that allow you to consume a decent amount of carbohydrates in quite a small hit, like Science In Sport’s Beta Fuel. Again, consider what products you would like to explore and make sure that you’re practising with them. Don’t stress about whether this brand is better than this brand. By and large, they’re going to help you with the same thing.
Are there common mistakes people make with their marathon fuelling?
The big one is waiting until the week of the marathon to start considering how your food is influencing your training and performance. We’re creatures of habit, we need to train our guts and get used to having certain amounts of fuel available and using it. That requires training. If you are going to carbohydrate-load, practise during the 12 weeks what those meals the day before look like – because a lot of people can wake up on event day and feel heavy and sluggish. Every gram of glycogen stored is bound to 2.7g of water. So you know you’re going to wake up a bit heavier than normal. It’s good to practise running at that weight.
How can a nutrition planner like Hexis help?
Nutrition has lagged behind in the technology space for a while. We’ve seen things, such as wearables, help people understand their training more and how to periodise. But most people are still just tracking calories and eating the same thing each day, whether they’re doing 90 minutes of high-intensity intervals or a 45-minute steady run. We need to adjust our intake according to the demands of the activity. We’ve built a platform that will ingest your training data, and it will predictively plan, personalise and periodise how you should be adjusting your nutrition on a meal-by-meal basis to fuel and recover from your training. It can help ensure you’re not over- or under-fuelling.