What to Eat During a Marathon Race

Completing a marathon requires not only rigorous training but also strategic fuelling to ensure your body has the energy it needs to cross the finish line. While carbohydrates are universally acknowledged as the primary fuel source for endurance events, determining the optimal amount to consume during a marathon can be a puzzle. Here’s how to approach mid-run nutrition with a blend of science and personalisation to enhance performance.

Carbohydrates are the marathon runner’s fuel of choice, providing the quick energy needed to sustain effort over the long haul. However, the body’s carbohydrate stores are limited, typically running low as you approach the latter stages of a marathon. Research in endurance sports has shown that consuming carbohydrates during exercise not only supplies additional fuel but can significantly improve performance.

General guidelines suggest that for activities lasting 2-3 hours, intake should be around 60 grams of carbohydrates per hour. For longer durations, exceeding 2.5 hours, the recommendation increases to up to 90 grams per hour, utilising a mix of glucose and fructose to enhance absorption and fuel availability.

Interestingly, real-world intake among marathon runners often falls short of these recommendations. Studies indicate an average consumption closer to 35 grams per hour, suggesting many runners might not be fully capitalising on the potential performance benefits of optimal carbohydrate intake.

The question then arises: should runners aim for the higher intake of 3 gels per hour, equating to roughly 60 grams of carbohydrates, along with adequate hydration? A study published in the International Journal of Sport Nutrition and Exercise Metabolism presents compelling evidence in favour of a structured nutrition strategy. Runners adhering to a plan consuming 60 grams of carbohydrates, 60 milligrams of sodium, and 90 milligrams of caffeine per hour, alongside 750ml of water, demonstrated a significant 4.7% average improvement in their marathon times compared to those following their usual nutrition habits.

1. Start Early: Begin fuelling before the beginning of the marathon to prevent glycogen depletion. Adjust the timing based on the intensity of your run and personal digestive comfort.
2. Practice Makes Perfect: Utilise longer training runs and preparatory races to refine your nutrition strategy. Experiment with different carbohydrate sources, including gels, chews, and sports drinks, to find what works best for you.
3. Hydrate Strategically: Balance your carbohydrate intake with adequate hydration, considering both water and electrolyte replacement, to support absorption and maintain hydration status.
4. Listen to Your Body: While guidelines provide a starting point, individual needs can vary. Factors such as pace, fitness level, and environmental conditions all influence your specific requirements.

Embracing a science-based approach to mid-run nutrition, tailored to your personal needs and preferences, can offer a distinct performance advantage. By aiming to meet or approximate the carbohydrate intake recommendations, you ensure your body has the fuel it needs to sustain effort, delay fatigue, and optimise marathon performance. Remember, the best fuelling strategy is one that’s practised, perfected, and personalised, allowing you to run your best marathon yet.