Long runs and marathon training demand more than mental grit and strong legs; they require a smart nutrition strategy. The right fuel helps maintain energy, supports hydration, delays fatigue, and improves recovery, allowing you to train consistently and perform at your best. Whether you’re building distance or preparing for race day, understanding how and when to fuel can make every mile feel more controlled.

As run duration increases, the body’s stored carbohydrates begin to deplete. Once glycogen levels drop too low, fatigue rises sharply, and pace becomes difficult to maintain. Long-run nutrition is about replacing energy as you use it, while supporting hydration and muscle function, so performance stays steady rather than fading.

As performance levels drop, it is incredibly important to find effective ways to replace energy, which is why practicing your running nutrition is essential before running a marathon. 

For long runs, the primary goal of nutrition is to maintain energy levels, prevent glycogen depletion, and support muscle repair. This means the main nutrients to target are carbohydrates, fluids, and electrolytes.

• Carbohydrates - Carbohydrates are broken down into glucose for immediate energy or stored as glycogen in the muscles and liver. Runners should aim to consume 30-60 grams of carbohydrates per hour during runs that are longer than 60-90 minutes. 

• Hydration and Electrolytes - Proper hydration prevents premature fatigue, while electrolytes are vital. Aim to drink 150ml-300ml every 15-20 minutes. 

There are plenty of healthy foods that can be used to fuel your runs, whether that be before the run or during training. Here are some of the best foods you can incorporate into your diet to improve your nutrition:

Carbohydrate Sources:

• Porridge overnight oats with fruit or honey

• Rice, pasta, and potatoes

• Wholegrain or white bread, bagels, and wraps

• Bananas, dates, and dried fruit

• Yogurt with granola or muesli

Pre-run and race-morning foods:

• Toast or bagel with honey or jam

• Rice pudding

• Banana or apple sauce

• Energy bars made with natural ingredients

During-run Fuelling:

• Energy gels with natural carbohydrates

• Energy chews

• Soft energy bars broken into small pieces

• Dried fruit such as dates or raisins

• Sports drinks containing carbohydrates and electrolytes

Hydration and Electrolytes:

• Electrolyte drinks with sodium

• Electrolyte powders or tablets

• Coconut water (with added sodium if needed)

Long runs are the ideal opportunity to practise your nutrition strategy. What you eat, how much you take on, and when you consume it should all be tested in training rather than left to chance on race day. Everyone’s tolerance and needs are different, so learning what works for your body is just as important as building mileage.

A well-planned nutrition approach turns long runs from a test of endurance into a controlled, confidence-building session. By fuelling consistently, staying hydrated, and supporting recovery, you allow your body to work efficiently over distance. 

Whilst there are many foods to target throughout your training, there are also foods that you should try to avoid. For example, some of these foods can cause stomach issues, and that is the last thing you want whilst in marathon training. Here, we have compiled a list of different foods that we recommend you avoid:

• Spicy Foods

• Fatty Foods

• Foods High In Fibre

• Dairy Products

• Fried Foods

• Protein Bars

• Alcohol

The above food items are more likely to cause stomach upset and discomfort. Some may contribute to cramping, bloating, and even dehydration.

Marathon fuelling doesn’t need to be complicated, but it does need to be consistent. Choosing the right foods and products to support training, race-day performance, and recovery helps keep energy levels steady and fatigue at bay. By focusing on carbohydrates, hydration, and electrolytes, and practising your strategy during long runs, you can arrive on the start line confident that your nutrition will carry you through every mile. Fuel well, trust the process, and give your body what it needs to go the distance.