The nutrition plan for ultra-trail preparation enters a critical phase in the final two weeks before the race. This period must be managed carefully to provide your body with the essentials it needs to be race-ready. Not sure what to eat before your ultra? Follow the guide.
Nutrition in the final two weeks before the race
Meals in the final week must anticipate the high energy demands of the event, aiming to keep your metabolism performing at its peak. Plan for three to four meals a day, without overeating or snacking between meals. Total daily intake typically ranges between 2,400 and 3,500 kcal depending on individual profile, with roughly 20 to 25% fat, 15% protein, and 60% carbohydrates. Maintaining proper hydration is equally vital, drinking 1.5 to 2 litres of fluid daily outside of training.
These values are guidelines, not a strict prescription: individual needs vary significantly based on body size, gender, training volume, and metabolism. If you have any doubts, or specific digestive or medical history, a sports dietitian will be able to tailor these targets to your needs.
The final days
At 3 days out (D-3), it is crucial to switch to a high-carbohydrate diet tailored for endurance athletes. This involves taking in 65 to 70% carbohydrates daily, with a strong focus on complex carbs at every meal, naturally including starchy foods and bread. The goal is to maximize muscle glycogen stores: to achieve this, eat two large plates of starchy carbs per day, bread with every meal, and cereal or porridge in the morning if possible.
A side effect to expect so you do not worry: this carb loading comes with a weight gain of one to two kilos, as each gram of stored glycogen holds around three grams of water. This is normal, desirable, and this water will serve you well during the race.
Race day
The final pre-race meal is ideally eaten 3 to 4 hours before the start: simple, well-cooked carbohydrates (white rice, white pasta), an optional small portion of lean protein, and an easily digestible dessert like fruit compote or a ripe banana. Avoid fibre and fat, which slow down digestion and increase the risk of GI distress during the race. A light snack can top things up 1 hour to 1 hr 30 mins before the start: a slice of white bread with honey, or a few sips of sports drink if your main meal was eaten earlier.
A specific detail for the UTMB®: the flagship race starts on Friday at 17:45. The "final meal" is therefore not breakfast but a late lunch, eaten around 13:30 or 14:00. Many runners are caught off guard by this timing and arrive at the start line with their stomach either too full or completely empty.
Golden rule: never try unfamiliar food on race day; everything must be thoroughly tested in training.
Frequently asked questions
What should you eat before the start of the UTMB®?
A meal eaten 3 to 4 hours before the start, based on simple carbohydrates (white rice or pasta), a small serving of lean protein, and an easy-to-digest dessert like a ripe banana. Since the start is at 17:45, this serves as a late lunch.
What foods should you avoid the day before an ultra-trail?
Foods rich in fibre (raw vegetables, pulses/legumes) and fat, which slow down digestion and increase the risk of stomach issues on race day.
Is it normal to gain weight during carb loading?
Yes. Gaining one to two kilos is common, as stored glycogen retains water. This is a sign that your carb load is working, and this water will be drawn upon during the race.
Find out more
- Gut training for ultra-trail
- Nutrition and hydration strategy for the UTMB®
- Nutrition plan and diet for UTMB® preparation
Photo credits: Delphine Daniélou.
