What to eat if you’re running a marathon

We speak to a top sports nutritionist about breakfasts and expert hydration

What to eat if you’re running a marathon

Are you running a marathon this year? If so, you'll probably want to know what you should be eating and drinking, to boost performance and ensure you're well hydrated – and to generally stay in tip top shape.

Thankfully, Steve Grant, a London-based nutritionist specialising in sport & performance nutrition, has filled us in on all the ways to best fuel your body when training for a big race.

It turns out it’s actually easier than you might think... Here are Steve's top tips to set yourself up for a smashing PB.

What should you eat for breakfast before a big run? 

"For most people, a balanced breakfast of proteins, fats and carbohydrates works well, but nothing so large it makes your digestive system feel uncomfortable leaving you tired and sluggish," says Steve.

"A great breakfast to set you up might include some starchy carbohydrates like oats, rice, or bananas with a form of protein such as eggs, fish, or protein powder, topped with nuts, seeds, coconut oil or yogurt for a portion of fat."

We think you can't beat a bowl of porridge! See our basic recipe, and feel free to add nuts, seeds, yoghurt, fruit or powders as desired.

Is there anything you should eat or drink if you want to beat your personal best? 

There’s no magical food that can substitute consistent training and a well thought-out diet, according to Steve. 

"Nevertheless, a good insider's tip is to consume foods rich in nitrates before a race, such as beetroot juice and spinach. Nitrates break down into nitrites that get turned into nitric oxide as needed. Nitric oxide can increase circulation and improve aerobic performance, blood flow, energy output and even recovery."

What foods should be avoided during training?

This depends on what your digestion can handle.

"In general, avoid anything heavy before training or the event — meats and very high fat levels are harder to digest."

For Steve, consuming liquid meals before working out is a great way to keep things light while still getting all the energy and nutrients you need.

"Personally, I prefer liquid nutrition such as shakes and homemade smoothies with powdered electrolytes (salts), amino acids (proteins) and powdered carbohydrates,” says Steve. “Liquids don’t put a stress on the system in the same way that solid foods do".

Our vibrant, healthy smoothie bowl is a great way to pack in a few of your five-a-day while training, too.

What foods should be avoided on the big day? 

When it comes to fuelling your run on the big day, Steve advises that you stick to what you know.

"Everything should be tried and tested before the big day — you shouldn’t be trying anything new on the day of your marathon.

"I know plenty of stories about people not making it to the finish line because of sugary electrolyte gel packs. If you used gels during training and know they work for you, they can be a good addition to your nutrition — otherwise, stick to what you know."

How important is it to stay hydrated? 

"Water is crucial for a number of reasons," says Steve. "It acts as a lubricant, supports energy production, is a temperature regulator and helps transport nutrients and compounds around the body. Even very minor dehydration can lead to reduced aerobic endurance, reduced muscle strength and an increased risk of cramp." And nobody wants cramp...

The best way to stay hydrated is through drinking water, but in marathon training Steve suggests replacing salts with a a good electrolyte formula diluted in water. He says, "Get your body used to the supplement and keep your hydration in tip top shape."

What are the best foods to eat after a race to replenish your body? 

Unless you're Mo Farah, a well-balanced diet and a decent amount of rest and recovery are your best options, according to Steve.

He says, "Replenish your body with a good mix of energy-filled foods such as plenty of fruits and vegetables, wholegrains, protein-rich foods such as chicken and other lean meats, lentils, pulses and quinoa, and some healthy fats such as avocado, olives, nuts and nut butters, seeds and coconut."

This might sound like a "boring" reward after all your hard work, but it’s easy to get creative when eating a balanced diet. A lean beef or grilled chicken burger in a wholemeal bun with avocado, tomato and spinach ticks all your food groups and still feels like a treat! Try this zesty chicken burger with sweet potato fries. Also healthy while still feeling like a treat? This comforting lentil bolognese with courgetti… yum! You could satisfy your sweet tooth with our Kiwi Eton Mess for afters…

Getting ready to run in the London marathon? Make sure you're stocked up on everything you need, including our amazing range of sportswearat Asda or pop into your local store.