He took up trail running on a dare and finished the Diagonale des Fous, the crazy story of rugby player Mathieu Lezeau

Some bets change a life. Mathieu Lezeau’s was born over a drink, somewhere on Réunion, among friends and childhood memories. A challenge thrown down lightly. A handshake. And, behind it, a promise impossible to ignore.

“Someone told me about the Grand Raid and the Diagonale des Fous. I said, laughing, that it was an insane thing to do and that I’d never manage it“, he remembers. His friend pushed him, needled him a little. The rugby player’s ego did the rest. “He told me I was all talk. So I shook his hand and said I was going to do it.“

A year later, he was crossing the finish line.

The school of rugby

At first glance, nothing marked Mathieu Lezeau out for ultra-trail running. At 33, this father of two and social media content creator grew up above all in the world of the oval ball. An early passion, almost a family one.

“I started going to watch matches with my grandfather. At first, I played on the touchline with the players’ kids. Then I put the boots on at about 7 or 8.“

Rugby quickly became more than a sport. “I discovered a wonderful world. Mini-rugby really is the school of life. It gave me a framework.”

Brought through in Charente-Maritime, near La Rochelle, he discovered competition in Fédérale 2. A wing by trade, quick but solid, an atypical build for the position. “I was a big wing. Not very tall, 1.73 m, but around 100 kilos.”

The player’s path also took in the army, then Saint-Barthélemy, before a return to mainland France. At Chauvigny, in Régionale 2, he rediscovered the essence of amateur rugby. “At first, I thought the level was going to be tricky. And then I discovered something else. Mates, an atmosphere, real village rugby.”

Raw rugby. Sometimes chaotic. Always intense. “There’s an incredible physical intensity. Paradoxically, it’s sometimes more dangerous. The lads turn up on Sunday still carrying three grams of alcohol and they start clattering each other.“

The injury that changed everything

The turning point came brutally. A ruptured cruciate ligament, on a rutted pitch. A “potato field ploughed up by moles“.

“I was at the back, I tried to clear with my foot and my foot stayed stuck in a clod of earth. The knee went.”

A year of rehab. And above all the doubt. “I’d never been injured before. When you come back, you always have that fear of doing the knee again. It wasn’t the same any more.“

At 33, Lezeau finally chose to hang up his boots. “I still have my licence, so if I want to play this weekend I can. But I preferred to stop. When you play a match at that age, it takes you longer to get over it.”

What came next was written far from the pitches.

The metamorphosis

The spark came almost by chance during an improvised honeymoon. Destination Réunion, almost by default. “We were supposed to go to Mauritius but my wife lost her passport, he says, a little sheepishly. We looked at the flights and we saw Réunion.”

Out there, he met up with a childhood friend with whom he had shared fifteen years of rugby. And discovered the world of trail running. The challenge was thrown down. The bet was taken.

On 15 October 2024, on getting home, he started training. “I knew that to prepare for a race like that, you needed a year.“

The transformation was spectacular. Without any particular diet, simply through the effect of training. “The body adapts. When I started running, it decided I was too heavy. In six months, I lost 25 kilos.“

From 100 kilos on the wing on rugby pitches to under 80 on the trails. “Today I weigh 78 kilos and I feel good. I’m not saying I fly, but it’s not far off.“

The hell of the Diagonale

The Diagonale des Fous remains one of the most fearsome ultra-trails in the world. More than 160 kilometres, thousands of metres of climbing and a full crossing of the island.

Even for a seasoned athlete, the event is merciless. “It’s the hardest thing I’ve done in my life.”

In the middle of the night, on the slopes of the Maïdo, doubt set in. “At one point I told myself it was impossible. I’d already done 80 kilometres and I still had 100 to go.”

At Cilaos, at almost 2000 metres of altitude, he even considered pulling out. “I wanted to hand in my number. Luckily, my wife and my wedding witnesses were there. They lifted me back up.“

The rugby player then went back to his fundamentals. “In rugby, you’re taught never to give up on anything. Even if you’re 50 points down. That’s exactly what I found again in trail running.”

He set off again. And he finished.

The ultra bug

The Diagonale des Fous lives up to its name. Many come out of it inoculated. Others infected for life. Mathieu Lezeau clearly belongs to the second category. “When you do it, either it puts you off completely, or you go totally mad and you want to go back.“

He has already made his choice. “I’ve entered again for 2026. If the ballot smiles on me, I’m going back.” With one target in mind. “My dream would be to finish in the top hundred one day.“

In the meantime, he keeps running, keeps improving, and is telling the story of this transformation in a documentary film that will come out on 1 May on YouTube.

A whole year of preparation and metamorphosis. “The story is so beautiful that I wanted to share it.“

A story in which a rugby player discovers that endurance can also be a form of combat. And that, sometimes, the greatest adventures begin quite simply with a bet between friends.