marathon nutrition

Marathon Nutrition by Registered Dietitian Laura Clark

marathon nutrition

Vicki and I both have friends training for the marathon next year. Hats off to them as for me simply completing a week’s tasks and basic exercise feels like a marathon effort.

If you’re a parent and also fitting in training, planning is key! Whilst a run can be a welcome break from parenting or work duties, you may find you’re half way through it before you realise you didn’t really eat or drink very much or the right thing before you headed out.

Marathon nutrition is important. Not only does it need to support your training plan but what you choose to eat and drink whilst running can have a big impact on getting across that finish line in one piece, not to mention the potential it gives you to deliver a PB.

Anything you try on race day itself should be practised in training. You will be running high on hormones when it comes to the race and unexpected foods or timings can throw you already quivering gut into a spin.

You may be following a specific training plan or winging it slightly. Whichever way, once you’re runs are over an hour in length (consistently running over 7 or 8 miles) then nutrition becomes more important. So, what should you eat?


Should I eat lots of carbs?

To a certain extent but it is relative to your body weight. On a training day, the average marathon runner needs around 5g carbohydrate per kg of body weight when runs are lasting longer than an hour. This equates to 300g if you weigh 60kg. To put this into context a fist size of pasta is around 40-45g and a small apple is 10g. An example meal plan showing how to achieve 300g is shown below.

Consider what your baseline carbohydrate intake looks like as this may need to increase. If you’re used to being cautious over carbohydrate portions, then they need to shift to at least a third of the plate. Typically, this would be wholegrain varieties of rice, pasta, couscous, noodles or baked potato for example but if you’re increasing your carbs you may find you need to build your intake of fibre up gradually. You can also boost carbohydrate stores with yogurt, fruit and pulses. It is a myth to assume vegetables will provide a significant carbohydrate source. A whole plate of courgetti will only give you around 4g of carb!

I often find people have low carbohydrate lunches – a bowl of soup or a salad for example are not going to provide enough fuel. You’re aiming to always keen glycogen stores topped up. This is the storage form of glucose in your muscles and a little is also stored in your liver. Your muscle is like a reservoir for glycogen storage – another good reason to maintain and build a good lean muscle mass as it increases the body’s capacity to store fuel without having to convert it to fat. You will need some carbohydrate in snacks twice a day as well as carbs at meal times to ensure you get enough, especially as your miles rank up.

When snacking, if you put some protein with it, it will help regulate hunger pangs. For example, some oatcakes and nut butter, a small bowl of cereal or half a sandwich with some hummus or chicken; useful if you’ve large gaps between meals. Pulse- based snacks are a great carb and protein provider and a healthy alternative to crisps. Nuts although a common snack contain no carb so will not fuel muscles as such. Worth remembering this as handfuls can be high in calories. To get enough carb in without taking on unnecessary calories don’t be afraid of pure carb snacks. Malt loaf for example is a runners’ favourite.


So, do I need to eat lots of protein?

No – For long distance running timing of protein intake is far more important than amounts. The average British diet already contains sufficient protein (around 1g/kg body weight) for muscle repair without the need for expensive protein supplements or shakes.

Protein is key for after training to support repair of muscles. There is no refuel window that suddenly closes whilst you’re busy putting the children to bed but aim to eat a balanced meal within 2 -3 hours of completing your run.


Should I drink plenty?

Yes, but there is a catch! Every runner should have a hydration strategy that they’ve practised in training. During training and daily life, it’s important to give yourself reminders to drink. Downing a pint of water before you head out doesn’t hydrate you as the fluid isn’t in the cells where it’s needed. It’s important to pace your drinking – if you’re thirsty you’re already getting dehydrated and it’s impossible to replace big fluid losses quickly.

Avoiding dehydration is essential as in an average marathon, you will sweat anywhere between 500 mls and 1.5 L per hour and even more in hot weather.

Sports drinks are an excellent way to replace fluids and electrolytes lost through sweat, but you should balance your drinking according to your sweat rates, as well as what your stomach can tolerate as you run. Also, be aware that over drinking particularly of water alone can have dangerous consequences.


So, what should my race nutrition strategy be?

It is physically impossible for the body to store enough carbs to fuel a marathon, so you will need to refuel whilst running to prevent fatigue. Your body needs 30-60 g carbohydrate per hour, for example 500 mls sports drink, 2 sports gels or 12 jelly babies.

You need to practice this in training though as individual tolerance varies and it’s essential to find a refuelling strategy that works for you. You can also train your gut to become more tolerant.

Example meal plan providing 300 g carbohydrate…

Breakfast 50 g no added sugar muesli

Plenty of milk (135 mls)

1 small banana

Mid- morning snack A slice malt loaf

One apple

Lunch Apricot, quinoa and chickpea salad:

Mix together 80g cooked quinoa, drained small tin chickpeas, 3 chopped dried apricots, ¼ avocado, 1 tbsp raisins, 1/3 courgette chopped into matchsticks, a handful of watercress and a few mint leaves. Separately mix a clove of garlic, 1 tsp tahini, a decent squeeze lemon juice and dollop of fat free Greek yogurt. Add the dressing and put a sprinkle of mixed seeds to serve.

250 mls fruit- based smoothie (shop bought or homemade)

Afternoon snack or pudding Greek style natural yogurt (150g)

Large handful blueberries

10 almonds

2 tsp honey

Dinner 200 g cooked rice

1 salmon steak

Steamed veg e.g. Tenderstem and runner beans

Lovely recipe by Vicki here

During a run 750 mls 6% carbohydrate isotonic sports drink

If you’re following a vegan diet, you could adjust as follows and still meet your carb needs:

Breakfast 50g no added sugar muesli

Plenty of soya or oat milk (135mls)

1 small banana

Mid- morning snack A slice malt loaf

One apple

Lunch Dhal with almonds and fresh coriander.

Heat an onion and garlic with cumin and ground coriander. Add 125g red lentils and 400mls stock together with 2 carrots.

Cover and simmer, adding 125g frozen peas 5 mins before serving. Stir in lemon juice, salt and handful of fresh coriander and serve with 100g cooked basmati or brown rice.

250mls fruit- based smoothie (shop bought or homemade)

Afternoon snack or pudding Coconut yogurt (100g)

Small banana

Handful of walnuts

2 tsp maple syrup

Dinner Chickpeas with couscous

Lovely recipe by Vicki here which serves the whole family. To ensure you have enough of what you need ensure there’s half a tin of chickpeas and 100g cooked cous cous for you.

During a run 750mls 6% carbohydrate isotonic sports drink


Keep up to date with Laura’s siteblogFBTwitter and Instagram.

If you want to see me or any other registered dietitian for advice check out

Read more of Laura’s posts here: How to Lose Weight as a Busy MamaFood Assumptions and How They Affect Their Children, and Confessions of a Dietitian Mum: What I Actually Feed My Children.


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