Marathon Prep: Your Nutrition Strategy for the Final Weeks

The weeks before a marathon are often where the biggest race-day mistakes actually happen, not during the 42.2 km themselves. Good physical training isn't enough if your nutrition strategy hasn't been tested. Here's how to structure your approach, week by week, so you arrive at the start line with a clear plan.

1. 8 to 4 weeks out: training your carb tolerance

Your stomach trains just as much as your legs do. A carb intake you've never tested in training has no place on race day. Use your long runs to test your stack: how many carbs per hour does your system handle well under effort? This is also the time to identify your preferred flavor and format, not race week.

A realistic target for most recreational runners sits between 30g and 60g of carbohydrates per hour, adjusted for your size and pace. Write down what works in a training log, you'll come back to it during race week.

2. Race week: carb-loading without overcomplicating it

Carb loading doesn't need to be complicated. In the 2 to 3 days before the race, slightly increase the carb portion of each meal (rice, pasta, bread, fruit) without radically changing your usual diet. The goal is to maximize glycogen stores, not to test new foods.

Stick to familiar foods. This is the worst time to discover something doesn't agree with you digestively.

3. Race morning: timing your last intake

Aim for a full last meal 2 to 3 hours before the start, then a light, slow-release carb intake about 30 to 60 minutes before the gun goes off. This is the ideal moment for an endurance drink like Eracer: it stabilizes your starting blood sugar without weighing down your stomach before the effort.

4. During the race: how many carbs per hour?

Once you're off, stick to the rhythm you validated in training. For efforts over 90 minutes, targeting 30g to 60g of carbohydrates per hour remains the standard for most runners, with a steady electrolyte intake to prevent cramps, especially in hot conditions.

Consume regularly rather than in large, spaced-out amounts: small, frequent intakes are better tolerated than a massive dose once an hour. Still torn between gels and a drink? This comparison will help you decide.

5. Mistakes to avoid

Trying a new gel, drink, or food on race day.
Under-fueling the first 30 km thinking you're "saving your reserves."
Drinking only water for more than 90 minutes of effort, without replacing lost electrolytes.
Changing your sleep or eating routine in the 48 hours before the start.

6. Where Eracer fits into your routine

Our isomaltulose formula is built exactly for this scenario: stable energy, no spike or crash, combined with complete electrolytes and vitamins B1, B6, B12 to support energy conversion. Work it into your long training runs to validate your tolerance, then repeat the exact same routine on marathon day.

The best nutrition strategy isn't the most complex one, it's the one you've tested, repeated, and trust before you even show up at the start line.

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This content is for informational purposes only and does not replace advice from a healthcare professional or registered dietitian. Consult a professional before changing your sports nutrition strategy, especially if you have a medical condition.