Training for a marathon is about more than just running. Nutrition plays a critical role in how well you perform — and how you feel— on race day. The right fuel helps you sustain energy, avoid fatigue, and recover faster.

But eating for marathon success doesn’t start the night before. To truly optimise your performance, you need to start fuelling correctly several days in advance, with a focus on carbs, hydration, and smart supplement support.

The week leading up to your marathon is the time to maximise glycogen stores — your body’s primary fuel for endurance. This is where carb-loading comes into play.

Carb-loading involves increasing your carbohydrate intake in the 3–4 days before your race to fully stock your muscles with glycogen. This energy reserve helps delay fatigue and improve endurance on race day.

Aim for meals that are rich in complex carbohydrates, moderate in protein, and low in fibre and fat to avoid digestion issues.

Unsure what to eat the week before a marathon? The following details what you can be eating to ensure the lead up to your race allows you to perform at your best.

5–7 Days Before Race: Balanced Nutrition

• Breakfast: Oats with banana, honey, and almond butter
• Lunch: Grilled chicken with quinoa, roasted veg, and hummus
• Dinner: Salmon with brown rice and steamed greens
• Snacks: Greek yoghurt, energy bars, rice cakes, electrolyte drinks

2–3 Days Before Race: Carb Loading Begins

• Breakfast: Whole grain toast with jam + low-fat milk
• Lunch: Pasta with tomato sauce and lean turkey
• Dinner: White rice with mild curry and lean protein

Snacks: Bananas, energy chews, Puresport Electrolytes

The 24 hours before your race are all about easy-to-digest, carb-rich foods, while avoiding anything new or heavy.

Food For Night Before Race:

• Stick to a familiar meal: white pasta with a simple tomato or olive oil-based sauce and lean protein like grilled chicken or tofu
• Avoid creamy sauces, high-fibre veg, or anything spicy
• Keep portion sizes moderate — you don’t want to feel overly full

Food For Morning of Race:

• Eat 2–3 hours before the start
• Good options include:
• Bagel with peanut butter and banana
• Porridge with honey and berries
• Rice cake with jam and a protein shake

Rest is just as important as fuelling. Poor sleep can negatively impact your energy levels and race-day mindset. Try Puresport’s natural Sleep Supplements the night before to help calm nerves and encourage deep, restorative rest.

Alongside a solid nutrition plan, smart supplementation can help you stay energised, hydrated, and focused in the lead-up to your race. Puresport have a range of supplements designed to help you maximise your race-day performance.

• Electrolytes – Prevent dehydration and cramps, essential in the days before and during the race.
• Creatine Monohydrate – Supports muscular endurance and recovery, perfect during the taper phase.
• Sleep Supplements – Promotes better sleep, particularly helpful the night before when pre-race nerves are high.

Certain foods can spell disaster on race day. Avoid anything that could disrupt digestion, cause bloating, or lead to energy crashes.

Avoid the following:

• High-fibre vegetables (broccoli, beans, cauliflower) – May cause bloating or gas
• New or unfamiliar foods – Stick to what your stomach knows
• Heavy, fatty meals – Can slow digestion and leave you feeling sluggish
• Spicy foods – May cause gut irritation and irregularity
• Alcohol – Dehydrates and impacts sleep quality immensely
• Too much caffeine – Can increase anxiety or lead to mid-race energy dips; as a diuretic it also affects hydration and water storage

Deciding what to eat before a marathon is a game-changer for running performance. Starting a week out, gradually increasing your carb intake, avoiding gut-disrupting foods, and using targeted supplements can help you arrive at the start line feeling strong, fuelled, and ready to go.

Need race-ready support? Explore the full Marathon Performance Supplement range to fine-tune your prep from training to taper.