When preparing for a HYROX race, we often think about training, race strategy, and penalties, but we often forget another crucial aspect: nutrition. How should we fuel (and hydrate) ourselves before and during the race to perform at our best? This is the question answered by Marie‑Caroline SAVELIEFF, a sports dietitian‑nutritionist.

You can book your consultation at FLAG with Marie‑Caroline SAVELIEFF, sports dietician‑nutritionist, on Doctolib.

What should you eat the day before the race?

The day before the race, there are two priorities: hydration and digestive comfort.

Hydration

Even mild dehydration impairs physical and cognitive abilities: reaction time, coordination, and the ability to maintain pace over repeated 1000m intervals.

The goal is to arrive on race day with optimal hydration levels, which can be adjusted according to weather conditions (humidity, heat).

Digestive comfort & energy reserves

The goal is to optimize energy reserves while minimizing digestive stress.

In practical terms:

‑ Choose easily digestible foods

‑ Reduce fiber (cooked fruits and vegetables, refined grains)

‑ And above all, stick to what you know: maintain habits you've already tested in training

The right balance: replenish your energy stores without disrupting digestive comfort

In practice, this means:

1. Drink regularly throughout the day, at least 35ml of water per kg of body weight. This includes at least 500ml of a bicarbonate‑rich drink such as Vichy Célestins, St Yorre, or an electrolyte drink.

2. Eat your usual breakfast, replacing your fresh fruit and whole‑wheat bread with applesauce and country bread, or your usual oatmeal, well‑cooked or blended to ensure digestibility.

Lunch and dinner can be vegetable‑free, allowing for a greater emphasis on refined starches. For example, white pasta with sliced ​​chicken in a light tomato sauce or rice with scrambled eggs.

What breakfast should you have if you're running early?

Two priorities: preserving sleep and ensuring energy reserves

The most important night is often the one before the race. But the night before a race, between stress, excitement, and the fear of oversleeping, sleep quality can suffer.

As a result, getting up very (too) early to eat isn't always the best option.

Here are two options:

1. If you get up 3 to 4 hours before your warm‑up: Keep your usual breakfast but choose a low‑fiber option (applesauce, cooked or ground oats, no nuts). Always test it beforehand.

2. If you get up less than 2 hours before your warm‑up: Easy‑to‑prepare snacks specifically designed for exercise: energy‑rich and easily digestible, often called "energy cakes," which can be eaten 1.5 hours before your warm‑up. These cakes can be made the day before and don't require any special skills: just a bowl, water, and an oven. There are also homemade recipes for purists.

But remember: test this breakfast beforehand and keep yourself lightly hydrated until your arrival.

What if we're out late in the evening?

The principles remain the same as the day before:
‑ Stay well hydrated,
‑ Choose simple, easily digestible meals that you've already tried.

The difference: these rules apply until lunchtime.

In the afternoon:

Time for a snack similar to the breakfast you had in the morning. Some simple ideas for a main course/dessert to take with you:
‑ Sliced ​​bread + 0% fat cream cheese + a slice of turkey ham
‑ Then a sweet touch: sliced ​​bread + peanut butter + mashed ripe banana.

For those with sensitive stomachs, the "good old plain crepe filled with applesauce" is a sure thing.

These snacks can be divided into smaller portions but should be eaten at least 1 hour and 30 minutes before exercise.

And what about gels, are they recommended?

2 important points:
‑ It's better to take nothing than to mismanage your intake.
‑ It's not the gel itself that matters, but the carbohydrate intake.

The right strategy: as soon as a sporting activity exceeds 1 hour, carbohydrate intake becomes beneficial.

‑ Consume 20 to 40g of carbohydrates per hour: fruit paste, applesauce, energy gel, gummies…
‑ Choose a carbohydrate dose (20 to 40g per hour) and a form (gel, applesauce, fruit paste) that you have already tested during intense exercise.
‑ Plan your gear for carrying during exercise (shorts, sports bra, arm warmers…)
‑ Plan your intake timing: run 3, 5?... depending on your target time.
‑ Ideally, drink 2‑3 sips of water to improve digestive tolerance.

In Hyrox, nutrition won't make you win, but a mistake can cost you: time, performance… and a lot of enjoyment.

Which is all the more frustrating considering all the training you've put in beforehand.