The day before the marathon

• Add a little extra salt to your meals. It helps regulate your fluid balance for race day.
• Drink more fluids than usual — but not so much that you need to use the bathroom constantly.
• Eat a carbohydrate-rich diet throughout the day. Think oatmeal, muesli, cornflakes, white bread, pasta, noodles, rice, and potatoes.
• Cut back on fiber, whole grains, protein, and fat. Instead, go for simple carbohydrates that are easy for your body to absorb.
• Avoid experimenting with new foods. Be kind to your stomach and skip very spicy or rich meals — don’t take any chances.
• Top up your carbohydrate intake with snacks like bread, crackers, muesli bars, fruit, dried fruit, candy, juice, or similar.
• Likewise, avoid using sports nutrition (such as gels or bars) on race day if you haven’t tested them during training.
• Familiarize yourself with the course and refreshment zones in advance so you have a clear plan. Also plan your transport to the start area to avoid unnecessary stress in the morning.

Race day morning

• Around 3 hours before the start, have a carbohydrate-rich breakfast. This could be white bread, rolls with jam, honey or Nutella, cornflakes, oatmeal/porridge, or similar.
• Again – don’t try anything new. Stick to foods you’ve had good experiences with during long training runs or previous races.
• You can drink fluids up until one hour before the start. After that, only drink if you’re thirsty. Drinking too much may cause you to flush out important salts and minerals your body needs.

Before the start

• Around 15–30 minutes before the start, it’s a good idea to have a small snack such as a banana, muesli bar, energy bar, gel, or a roll with chocolate spread, jam, or honey.
  This will give you a good energy boost for the course.

During the race

• Aim to consume a combination of water and energy (gels, sports drinks, bananas) every 20-30 minutes – for example at the refreshment zones. There are 10 refreshment zones along the course, all located on the right-hand side of the road.
• If it’s a warm day (above 18-20°C / 64-68°F), it can be a good idea to bring electrolytes such as salt tablets or salt sticks, which can be taken at the refreshment zones. This helps reduce the risk of dehydration and muscle cramps.
• Water and HIGH5 energy drink are available at all refreshment zones. Drink a little at each one – even if you don’t feel thirsty.

After the race

• Try to drink around one liter of fluid within the first hour after finishing. And keep hydrating throughout the rest of the day. Most runners lose the equivalent of 0.5-1 liter of fluid per hour during a marathon, so there’s a lot to replenish.
• Eat carbohydrate-rich foods in the hours after the race to support your recovery.
• Make sure to rest, sleep, and replenish your body’s energy stores in the days following the marathon.

The article is written by nutritionist Pernille Krogh Björklund and doctor Mads Münster Karlsson from Team Denmark. In their daily work, they advise some of Denmark’s top elite athletes on nutrition and training.