Interview de Mickaël Berthon, retour sur son exploit au GR5

Interview with Mickaël Berthon, looking back at his achievement on the GR5

Introducing Mickaël Berthon:

A passionate ultra-trail runner and Raidlight ambassador, his latest challenge is to cover the whole of the GR5, i.e. 2,163.55 km with 61,819 metres of ascent and descent.

The project was called Sea to sea, from the North Sea to the Mediterranean, a first that he completed with flying colours in 29 days, 22h and 39 min!

This exchange with Mickaël is full of feedback and advice of all kinds, so whether you're a beginner or an experienced rider, you're sure to enrich your human and sporting knowledge.

Here's a look back at some of his achievements:

Crossing the GR20 in Corsica from south to north on his own, June 2015
6 days, 190km and 14,000 metres of ascent

Finisher of the three Echappée Belle races
2016 Parcours des Crêtes 62km
2017 Traversée Nord 84km
2019 L'intégrale 149km

Finisher of the Diagonale des fous (Réunion) 165 km October 2021

Finisher of the Grand Raid des Pyrénées 220km August 2021

1st in the Infernal trail des Vosges, September 2021
200 km 10,000 metres of ascent, self-supported

2nd in the Red Dirt Ultra 100 miles in the USA, February 2022
160km 2500 metres of ascent

1st in the Val de Drôme Challenge, May 2022
136kms+42kms in 2 days

Fun Run (3 laps) on the Chartreuse Terminorum June 2022
One of the 5 finishers in the race that no-one has ever finished

Question: 1 Can you introduce yourself and your background in a few words?

Mickaël, 34, from Isère (38), I work as a mountain leader and trail coach. I started trail running 7 years ago, as I was very quickly attracted by the great distances and the adventure they offer, whether in competition or not.

I've always loved the great outdoors and I love being immersed in nature. When I left the army in 2014, I discovered that people were running in the mountains, which immediately intrigued me. I soon discovered that my hardiness, mental strength and excellent knowledge of my body were assets in ultra-distance running, a category in which I thrive the most and which has clearly become an all-consuming passion. I've always been self-taught in the discipline, a fervent believer that you have to do to be and that there's no substitute for experience.

Question 2: You've just set your first record time for the entire GR5, how do you feel after this crossing?

I'm fine and I feel like mission accomplished! I slept a bit more than usual for 10 days, which is normal. It's important to listen to your body, but physically my last wounds healed themselves and I was able to get back to work straight away. Obviously I'm gradually getting back into it with a few short outings, but my body and soul are already very keen to get back to work on new projects!

Question 3: A challenge like this has to be prepared months in advance, both physically and psychologically and in terms of the organisation itself. How did you manage the overall logistics, and more specifically the equipment and nutrition for this race?

The GR5 represents 2 years of mental preparation and commitment to myself and others.

In terms of logistics, I had one big advantage: my partner and my father followed me in my camper van for the whole of the crossing. It was a bit like coming home every evening, having all my equipment at my disposal and changing it according to the weather conditions of the day. Having people to assist me, available just for me, was the ultimate luxury.

Thanks to my long-distance experience, I knew exactly what to take with me, in my bag or my Raidlight shorts.

In terms of nutrition, I already knew what I needed to be self-sufficient for a day's running. What was new was repeating this effort 30 times in a row with the corresponding energy requirements, which corresponded to around 3 times the needs of a man with 'normal' physical activity. So we worked a lot on this point with Fiona, my partner, and Marion, a nutritionist friend, to optimise my intake without overloading the digestive system, for example by taking fruit or vegetable shakes, something new for me. I have to say that this is one of my greatest satisfactions, when you consider that it's a decisive factor in long-distance efforts, and everything worked really well.

Question 4: We know that you've been through a lot on this GR5, with very capricious weather, problems with the route and a lot of pain. What are your best and worst memories of the race?

The best memories are the moments of sharing, whether with my support team, the friends who joined me on the route, or all the people who supported and encouraged me.

But there are also all those hours of solitude that I love so much. The two create a perfect balance. Setting off from one sea to reach another also means an extremely rich variety of scenery that I keep in mind, despite the fact that I walked almost half of this GR5 in the rain. This is part of the rules of the game and in no way spoils the pleasure, quite the contrary, it makes it even more authentic.

I don't have any 'worst' memories, but there were some hard moments, like when I started to lose my fingers in a storm in the Jura, or when I couldn't run any more due to painful inflammations. I've never thought about giving up, but at times like that, time inevitably seems longer and the energy required to keep going is greater.

Question 5: This is the first time you've tackled a race of this scale, what have you learnt from it?

I was able to confirm that it was made for me! I liked it, I thought I liked it, but experiencing it really confirmed it for me. It was a first and I've already got plenty of parameters in my head that I could improve on for the next attempt on this scale. I like the feeling that I'm expanding my comfort zone, learning new things and emerging stronger from the challenges I set myself.

So obviously it requires a lot of investment, during the crossing but especially beforehand, in its preparation and then there's the financial aspect. I'd like to thank Raidlight for their material support, without that it would have been even more complicated.

I've also learnt that it's possible to do even better than this 1st time and I hope that someone else will try to improve on this record and I'd be delighted to help them.

Question 6: You've taken part in a variety of race formats, from short trails to ultra-trails and even multi-day GR events. Which format will you favour next and what are your next objectives?

There are still a lot of ultra-trail races that make me dream and that I'd like to run. I'm thinking of the TOR, which I'd like to try and win one day, if I can find the funding to get to the start line.

I'll continue to line up in different competition formats as I feel like it, but my main motivation remains to experience demanding, authentic and immersive adventures. Adventures that require a great deal of autonomy, such as this crossing of the GR5, are for me the very essence of trail-running and I want to remain faithful to them.

In February 2023, I'll be running the Legend Trail 250 in the Belgian Ardennes, an unmarked race renowned for its difficult weather conditions. I obviously have big ambitions for this race, but you have to remain humble in our discipline, where so many factors come into play that nothing can be taken for granted, and that's what makes it so exciting. You're always growing, whatever the ranking.

In June, I hope to be selected again for the Chartreuse Terminorum, the race of a lifetime. I'm devoting a lot of my year to finding a way to be one of the first, if not the first, to finish this race.

Beyond that, I've already got a few ideas for records that I'd like to try and improve in the years to come. But let me savour this one before revealing the rest ;-)

Question 7: Finally, we're all ears for your latest little tips and tricks for the trail enthusiasts who read us.

The first piece of advice I'd give to any runner who wants to improve is to experiment! Be curious and don't stick to your prejudices, your assumptions, or even your own playing field.

The second point, which ties in with the first, is that we're all different and what works for one person won't necessarily work for another, so avoid mimicry and discover yourself!

My 3rd piece of advice is that pleasure should always be your main driving force, and that you should run for love, not ambition.

Tip for long distances: create a running routine for yourself and break down your goal into several parts. Starting a race with the sole idea of reaching the finish line won't be enough for you. Personally, I have mini objectives for each hour of the race, which could be to eat something, to look at the distance already covered or to reach intermediate points during the race (feed stations, beautiful viewpoints, technical sections or, on the contrary, more rolling sections).

Thank you Mickaël for sharing your feedback and advice with us following your incredible adventure. The whole Raidlight team is proud to have supported you and congratulates you. We can only wish you every success in the future.
Thank you, I'd just like to conclude by thanking Raidlight for allowing us to live and share the trail running experience 😉


1 comment


  • Monique Pellet

    Un immense bravo à Mickaël pour avoir terminé le Chartreuse Terminorum, en deuxième place, et beaucoup d’admiration pour ce sportif très sympathique.
    De la part des 2 mamies rencontrées au sommet de la Scia, le lundi précédent le trail.