366 Marathons in 366 Days: Our Colleague Hilde Dosogne Talks About Her World Record

Our incredible colleague Hilde Dosogne, Senior Regulatory Affairs Manager, has accomplished something truly mind-blowing—she ran 366 marathons in 366 days! Yes, that’s one marathon every single day for a year (plus an extra one, for good luck 😉). We caught up with her to offer our congratulations and to hear all about her remarkable adventure!

Hilde, congratulations! How are you?
Hilde: “Thank you! I’m feeling well, though I’m still recovering from a bruised thigh. I even took an entire week off from running—unbelievable for me.”

Are you already thinking about your next run?
“Yes, I am. But no more one-marathon-a-day challenges—that was seriously tough! Last year, I ran over 15,000 km—that’s three times my usual distance. This year, I’m aiming to run the Spartathlon for the third time. (It’s a 246 km ultramarathon between Athens and Sparta, following the route of the ancient messenger Pheidippides, who ran this distance in 490 BC to request the Spartans’ assistance in a battle. Talk about old-school running!)”

What was the first thing you did after finishing your 366th marathon?
“Nothing extravagant—a hot bath! After that, my husband and I began preparing for New Year’s Eve at home. It wasn’t a grand celebration, but I truly enjoyed it. That final marathon was particularly challenging—someone bumped into me, and I fell! I still had 32 km left to run, so it turned into a genuine mental challenge.”

How proud are you of what you’ve done?
“Very proud! My main goal was simple: just finish. I never wanted to give up. Now that it’s over, I feel relieved. On cold, rainy days, I’m actually happy I don’t have to run. But this challenge was more about mental strength than running. I went through tough times, but I told myself I would only stop if I got seriously injured. Luckily, I had an amazing medical team to help me, and the support from BIG Against Breast Cancer kept me going. We raised an incredible €75,000 and even got international media attention.”

And now, a Guinness World Record?
“Yes, I’m in the process of submitting all the official evidence to Guinness World Records. It takes time—I still have a few weeks of paperwork before they review everything. I expect to receive a response in a month or two, but I’m quite confident they’ll validate it.” (Meanwhile, the world record has been officially confirmed! Read all about it.)

Why did you choose to run for BIG Against Breast Cancer?
“I met Valérie Van der Veeken at the Marathon des Sables in 2021 (a 250 km race in the Moroccan desert—yes, in the sand!). She works for BIG Against Breast Cancer and asked me to write a book ‘Highway to Hell. Hoe ik de 35e Marathon des Sables uitliep’ to help support the organisation. Since then, I’ve been raising money for BIG. I was also deeply moved by Joëlle’s story—she ran the Marathon des Sables after beating breast cancer, but unfortunately, her cancer returned. Now, she has brain metastases. Losing a childhood friend and a neighbour to breast cancer also inspired me to turn my passion for running into something meaningful.”

Were there any surprises along the way?
“The best part was the people. I loved running with strangers, friends, and supporters. One of my favourite surprises was Simon, a student who had never run more than 10 km before. He started running with me and ended up completing ten marathons in 2024. Seeing people push their own limits made this journey even more special.”

What keeps you running?
“Running brings me joy—both physically and mentally. One of my primary goals has been to inspire others to be more active. Just 5 km can truly impact someone’s life. I also enjoy involving my colleagues. Each year, some of us participate in the Ekiden relay, and in April, I organise a virtual Ekiden where people can run, walk, or cycle. It’s highly popular—over 100 Christeyns colleagues take part! We have trophies for the winners and small gifts for everyone.”

How did Christeyns support you?
“Christeyns sponsored my challenge, and so many colleagues ran with me. They even organised a special Christeyns Day, and some of my international colleagues came to cheer me on. On top of that, I was allowed to work part-time, and my team helped with my workload. Knowing I had so much support—both at work and in sports—made all the difference. I’m so grateful, and I want to keep promoting sports within the company.”

Message received loud and clear! Time to lace up our running shoes. 😉

Keep up to date with Hilde’s activities on Hilde Dosogne or her Facebook page.

 © Photos : Peter Vens