How to change your diet for a half-marathon - Women's Running UK

How to boost your diet for half marathon training

Author: Women's Running Magazine

Read Time:   |  May 16, 2022

Our top tips for the best nutrition to see you over the finish line

If you’ve signed up for a half marathon, you may need to make some dietary changes so that you’re well-fuelled to reach your goal, whether that’s achieving a PB or crossing that finish line for the first time. Here are some tips for keeping your energy levels topped up as you train.

1. Eat plenty of carbohydrates

Carbs provide the major source of energy for half marathon training, so it’s important to include enough in your diet (around 45-55 per cent of your calories), mostly from starchy plant foods and the natural sugars found in fruit and vegetables. Include a range of grains too, preferably wholegrains, such as oats, brown or basmati rice, rye bread and quinoa. Starchy vegetables such as white potatoes, sweet potatoes and butternut squash also provide good sources of energy.

2. Up your fruit and veg intake

As well as starchy veggies, aim to eat four to five other vegetables each day, such as leafy greens and colourful salads, and two to four pieces of different fruit. This amount of fruit and veg will give you a range of vitamins, antioxidants and other useful nutrients found in plants, which will reduce your risk of illness.

3. Try to include protein in all your meals

Around 15-20 per cent of your calories should come from protein. This is particularly important to help your muscles recover from training and to support your immune system. Consuming protein alongside carbohydrate will also help to prevent blood sugar spikes and encourage a steady release of energy during the day. Get your protein from meat, fish, eggs, milk, yogurt, cheese, nuts, seeds and pulses, depending on your individual dietary preference. You can also use protein powders in recovery drinks on your long-run days. If you are vegan, consider using plant protein powders to supplement your diet.

4. Don’t forget about healthy fats

Around 25-35 per cent of your calories should come from fats. Oily fish, avocado, olive oil, nuts and seeds help you to meet your calorie requirements, while providing a range of nutrients to support energy production, immunity and heart health.

5. Reduce added sugars

Keep added sugars to a minimum on days when you don’t run, to avoid those wobbly energy levels. But on harder run days, some honey with your breakfast or snack bars with plenty of natural ingredients, such as 9bars and Nakd bars, can work well.

6. Make sure you’re well fed

For every mile you run at a moderate pace, you burn around 100 calories. So if you run 20 miles a week, that’s 2,000 calories on top of those burned during your daily activities. Make sure to take those extra calories on board on run days, and increase your food intake gradually as your mileage builds. Your increased calories should come from carbs, while the amount of protein and fats that you consume should stay roughly the same.

7. Take on sports drinks or energy gels

Once you are running for over an hour, it’s a good idea to use sports drinks or energy gels to replenish muscle glycogen (stored carbohydrate) to sustain your pace and finish strong. Between 30g and 60g per hour of running should meet your carb needs. That’s one or two energy gels or 500-1,000ml of sports drink. You should also consume a recovery drink or bar with carbs and protein immediately after your long run, unless you can eat a full meal straightaway.

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