HYROX: is it really a good way to get back in shape?

HYROX: is it really a good way to get back in shape?

HYROX is everywhere. In gyms, on social media and now across major French cities, this competition blends running with functional exercises in an always-identical format. Its growth in France has been especially fast: HYROX France now claims more than 1,000 affiliated gyms, and several outlets reported around 100,000 participants in the country at the end of 2025.

But one question deserves to be asked behind the hype: is HYROX genuinely a good way to get back in shape, or has it mostly become the latest fitness trend?

The answer is broadly favourable — provided you understand what the discipline actually develops, and what it does not replace.

What is HYROX?

The principle is easy to grasp. A HYROX race alternates 1 km of running with a functional training station, eight times, for a total of 8 km of running and eight stations. The format is standardised, which makes performances comparable across events.

The stations include the SkiErg, sled push, sled pull, burpee broad jumps, rowing, farmer's carry, sandbag lunges and wall balls.

This creates an important particularity: the running never happens under the same conditions as a standard race. The kilometres are regularly interrupted by muscular efforts, and running resumes with fatigue already present.

That mixture is precisely what makes HYROX interesting.

A genuine cardiovascular demand

HYROX is not simply a series of exercises performed at high intensity. Running makes up a considerable share of the event and requires sustaining a cardiovascular effort for a relatively long time.

The first scientific study devoted specifically to HYROX analysed a simulation in 11 experienced recreational participants (each with at least one official competition behind them). Their median time was 86.5 minutes, most of it spent at a very high heart rate: roughly 80% of the time at an intensity described as 'very hard' and 20% at a 'hard' intensity. The researchers also observed that aerobic capacity (VO2max) was the factor most strongly associated with performance.

That gives a first useful indication: HYROX demands good cardiovascular endurance, not merely the ability to produce a few very intense efforts.

For anyone looking to improve general fitness, that is a clear advantage — a balance already explored in 'Cardio and strength training: can you progress in both?'.

And what about strength?

This is rather more nuanced.

Stations such as the sled push, sled pull, lunges, farmer's carry and wall balls place heavy demands on the muscles, particularly when performed after several kilometres of running.

But HYROX does not have quite the same objective as a resistance training session.

The available physiological study concludes that HYROX places moderate to low demands on maximal strength compared with other forms of high-intensity functional fitness. In that study, neither grip strength (used as a proxy for overall strength), nor muscle mass percentage, nor strength training volume predicted performance — only aerobic capacity, body fat percentage and endurance training volume were associated with it.

Some caution is needed about what this really means: the study captures an association between the physical profile of already-trained participants and their race speed; it does not demonstrate that training for HYROX makes you stronger. The difference between a statistical link and a real effect is detailed in 'Correlation or causation: why the difference matters'. In other words, HYROX can involve real muscular work and build a certain resilience, but nothing today allows us to claim it is an effective method for gaining strength or muscle mass in the sense resistance training means.

That is an important distinction before replacing resistance training entirely with HYROX.

Is it effective for losing fat?

HYROX places heavy demands on the cardiovascular system over a prolonged period, which suggests a high energy expenditure — even though no study has yet measured that expenditure in calories. But it would be misleading to present HYROX as a special fat-burning method.

Fat loss depends mainly on energy balance over time. A demanding physical activity can help raise energy expenditure, but it does not automatically offset a diet that supplies more energy than needed — a point developed in 'How to lose fat without losing muscle'.

HYROX can therefore be a useful tool within a fat-loss approach, particularly if you enjoy this kind of training and it helps you stay consistently active.

You simply shouldn't confuse a very tiring activity with a magic weight-loss method.

Is HYROX suitable for beginners?

This is probably the most important part for anyone looking to 'get back in shape'.

HYROX offers several formats — notably Open, Pro, Doubles and Relay — allowing you to choose a different level and set-up. The organisation itself presents the Open format as demanding but accessible.

But accessible does not mean easy.

A full competition means 8 km of running broken up by eight stations, at a high intensity for almost the entire event. It is worth noting that the available study was conducted on already-experienced participants — all had taken part in at least one HYROX competition, and the vast majority had very good to excellent aerobic capacity. So it says nothing directly about what a true beginner would experience over a full event.

If you are returning to sport after months or years of inactivity, immediately attempting to reproduce a full competition is probably not the best idea — all the more so given that the available data concern only well-practised participants.

It makes more sense to build the necessary qualities progressively: running regularly, strengthening the legs and trunk, learning the movements and gradually increasing training volume — the question of dosage is covered in 'What training frequency is ideal?'.

HYROX can be a fitness goal. It doesn't necessarily need to be the starting point.

HYROX or resistance training?

The answer depends mostly on what you are after.

If your main goal is to build as much muscle as possible, traditional resistance training offers far more precise control over volume, intensity and progression.

If you mainly want to become more enduring, more resilient and able to string together different kinds of efforts, HYROX becomes particularly interesting.

And you don't have to choose.

Combining resistance training with cardiovascular work can develop several physical qualities at once, provided total volume and recovery are managed properly.

HYROX can therefore complement resistance training rather than necessarily replace it.

The main trap: confusing intensity with effectiveness

This is probably the most important nuance.

A session that leaves you completely exhausted is not automatically better than a more moderate one.

HYROX is demanding by nature. The first dedicated study reports high levels of heart rate, lactate and perceived exertion during the simulation — with the highest values of all three observed during the very last exercise (wall balls), a sign that accumulated fatigue weighs right to the end.

But progress also depends on recovery, consistency and the ability to increase the training load gradually — see 'Are rest days really necessary?'.

For someone starting out, doing less but doing it regularly will probably be more useful than immediately chasing maximal intensity.

So, is HYROX really a good way to get back in shape?

Yes — with an important caveat.

HYROX combines cardiovascular endurance, muscular resilience and functional work in a format that gives training a concrete goal. The first available scientific data show a strong cardiovascular demand and suggest endurance plays an important role in performance — without, however, demonstrating that practising HYROX builds strength or muscle mass, which the study did not test.

Nor is it a universal method that would replace every other type of training.

For someone who enjoys running, lifting, challenging themselves and having a precise goal, HYROX can be a good way to develop fitness.

For someone whose main aim is to maximise muscle mass or strength, resistance training remains more specific.

And for a person only just starting to move again, the best HYROX is probably the one you prepare for progressively rather than the one you try to finish in your first week.

In short

HYROX probably deserves its success, but not because it is miraculous. It works mainly because it combines several physical qualities within a single activity and gives participants a concrete reason to keep training.

A trend can capture attention. Progress, on the other hand, still depends on regular training, recovery and an appropriate level of difficulty.

Editorial note: to date, a single published scientific study has analysed the physiological demands of HYROX, in a small sample of 11 already-experienced participants. The conclusions in this article therefore rest on still-limited data, and may be refined as research on this recent discipline advances.