Hyrox nutrition: what to eat before, during and after

What to eat in the days before Hyrox?

These recommendations are aimed at healthy adults who train. They are not a universal guide for minors, pregnancy, kidney disease or people taking medication: in those cases an individual assessment is needed before applying figures or supplements.

Preparation starts one or two days before. The real duration of your effort and your training load guide the carbohydrate plan. For these days, the joint position of the American College of Sports Medicine and the dietitians of the USA and Canada [1] guides carbohydrate needs according to the volume and load of your training.

Carbohydrates are spread across the meals of those days, with more rice, pasta, potato or bread in each dish. Choose carbohydrates with little fibre and low residue, so you can manage without stomach discomfort [1]. And keep fat in moderate amounts.

What to have for breakfast or lunch on race day?

Pre-race food should fill the tank and give you time to digest before warming up. For efforts lasting over an hour, the position proposes 1 to 4 g of carbohydrate per kilo, between one and four hours before [1]. At 70 kilos that is 70 to 280 g, depending on your margin.

If you start in the morning, two or three hours before, white toast with fresh cheese and jam works well. Fine oats with milk and banana also work. If you prefer a plant-based drink, check its composition and how it fits with the rest of breakfast. Bear in mind that soy is an allergen.

If you compete in the afternoon, have breakfast as usual and eat lunch three hours before. For example, white rice or pasta with grilled chicken breast, or boiled potato with French omelette and courgette. Keep that dish low in fat and fibre, so the stomach empties sooner [1].

What to drink and take during Hyrox?

Hydration starts before the start. Drink 5 to 10 ml of fluid per kilo in the two to four hours beforehand [1]. At 70 kilos that is 350 to 700 ml spread out, so you arrive hydrated without loading the bladder.

During the race, your time sets what you need. In intense efforts of 45 to 75 minutes, small amounts of carbohydrate may suffice, or even rinsing the mouth with a sports drink [1]. Between one and two and a half hours, the reference is 30 to 60 g of carbohydrate per hour [1].

If you expect an effort of between one and two and a half hours, a gel with water or a sports drink can contribute to the reference of 30 to 60 g per hour [1]. Practise the amount and timing during training sessions.

As for fluid, the reference is 0.4 to 0.8 litres per hour, adjusted to how much you sweat [1]. The position suggests limiting fluid deficit to less than 2 % of body weight [1]. Overdoing it also carries risk. Drinking water above what you sweat can cause hyponatraemia, a dangerous drop in blood sodium [1]. If during or after training, after drinking a lot, you feel nausea, headache or confusion, stop and call 112.

What to eat after Hyrox?

Crossing the finish line is the time to rehydrate, restore energy reserves and provide protein to recover muscle. The position proposes 1.25 to 1.5 litres per kilo of body weight lost for post-exercise rehydration, spread with foods or drinks that provide sodium [1]. The plan depends on your losses and recovery time.

If you have another demanding session within eight hours, the position proposes 1 to 1.2 g of carbohydrate per kilo per hour during the first four hours [1]. If you are not training again soon, organise recovery with the following meals.

For muscle, the International Society of Sports Nutrition proposes about 0.25 g of quality protein per kilo, or 20 to 40 g in total [2].

A systematic review found that taking carbohydrate after exercise replenishes muscle glycogen more than drinking water alone. Adding protein did not speed up that replenishment compared with carbohydrate alone [3]. This does not mean protein has no role in meals.

How much to eat on a normal training day?

Training running and strength together changes your needs. With one hour of moderate daily training, the reference is 5 to 7 g of carbohydrate per kilo per day [1]. If you train for one to three hours, 6 to 10 g [1].

To look after muscle, protein is 1.4 to 2.0 g per kilo per day [2], spread every three or four hours [2]. Fat falls between 20 % and 35 % of energy [1], and it is not advisable to go below 20 % routinely [1].

To fit these figures into your week, start from the basics of sports nutrition. If you want to gain muscle in pre-season, see the diet for fitness. If you also find it hard to gain weight, we work on it in the weight gain nutritionist consultation.

Do you need supplements for Hyrox?

Hyrox is full of supplement advertising, and very few have evidence behind them. The International Olympic Committee consensus studies possible small benefits of some supplements in high-performance athletes, such as caffeine, creatine or nitrate; for beta-alanine it notes a potential benefit [4]. That does not show a benefit for every Hyrox participant, so we do not claim that beta-alanine improves performance in amateur Hyrox.

Before considering any supplement, the priority is to adjust the basic diet, training planning and rest hours. The decision about supplements is individual.

Taking them on your own also carries another risk. Some products contain substances not listed on the label and can cause a positive result in an anti-doping test [4]. No supplement replaces eating enough and resting.

To organise strength days, see the diet for CrossFit and the weekly CrossFit menu. They are meal references; their amounts do not replace your race plan.

What Hyrox questions can we review in consultation?

We can review your pre-race food, access to drinks and your margin for recovery. Bring your race start time and the plan you have tried; that way we work with concrete decisions.

Among the most frequent mistakes we correct in consultation are:

• Loading up on carbohydrate only at dinner the night before. A huge plate of pasta sits heavy on your stomach the next morning, and the tank fills better when spread over one or two days.
• Skipping the pre-race meal out of nerves. Arriving without eating for a race lasting over an hour leaves little margin for the final stations.
• Drinking excessive amounts of water out of fear of dehydration. What you should drink depends on how much you sweat.
• Delaying recovery food if you have two sessions on the same day. Prepare an option to take during that interval.
• Copying the plan of a marathon runner or a bodybuilder. Hyrox demands endurance and strength at the same time, and the plan has to cover both.

If you eat less than you train

Running and strength together demand a lot of energy. If you cut meals while maintaining a demanding training load, there may be little energy left for the body’s functions once what is spent in exercise is subtracted. That energy availability is not the same as total calorie balance. The consensus distinguishes between adaptive low energy availability (which is temporary and controlled) and problematic situations that compromise health [5].

The International Olympic Committee consensus on relative energy deficiency in sport (REDs) describes what happens then [5]. Sustained insufficient energy availability compromises physical performance, hormonal balance and bone health [5].

If you notice constant tiredness or unexplained drops in performance, review what you eat with a dietitian-nutritionist before training more. If your period has stopped, go to your doctor first. And if eating has become a source of fear or guilt, the first step is specialist psychology.