Secrets to a fast Ironman Bike: How Maarten Seghers went under 5 hours
Secrets to a fast Ironman Bike: How Maarten Seghers went under 5 hours

The secret to a fast Ironman Bike leg: How Maarten Seghers dipped under 5 hours

Secrets to a fast Ironman Bike: How Maarten Seghers went under 5 hours

What does it take to ride a fast Ironman bike leg? Maarten Seghers reveals on this edition of The Kona Edge what it takes to ride a sub 5 hour Ironman bike.

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BRAD BROWN: Time to chat some Ironman biking. We head back to Belgium once again where cycling is huge. Our returning guest Maarten Seghers joins us now.

Maarten, welcome back. Cycling is one of your strong points. Between the run, it’s right up there. You had an incredible bike at Ironman Kona in  2016. Sub 5-hours which is fantastic, 4:54. What do you have to do to go under 5-hours on your Ironman bike?

The secret to a sub 5 hour Ironman bike leg

MAARTEN SEGHERS: Kona of course is the biggest race. Everyone comes out of the water at the same time. The first part of the bike was difficult getting away from the big groups because this year it was worse than previous years. But I kept on watching my Power meter and after the turning point it was more relaxed. I could ride at my own pace without worrying about the drafting.

I’ve only once had a violation card in my whole triathlon career and I don’t want to have it again. But in Kona it’s difficult. It’s not a secret. Just watch your Power meter and try to race the first part and the second part, the same. But  it’s not always that easy.

BRAD BROWN: For you, on your Power meter, what sort of numbers are you looking at?

MAARTEN SEGHERS: In Kona, I think I rode an average pace of 250 watts. Then my weight was 63 kg which was good.

BRAD BROWN: Fantastic.  You mentioned in our first chat, having that patience. Someone might come past you and you might be feeling good but you have to hold yourself back. That is vital, particularly  in Ironman racing.

Going out too hard burns all your matches

Because if you burn those biscuits up front, you’re going to pay later on in the race. Is that something you’ve had to work at or does it come easily to you? That you’re comfortable to let someone go because you know if you race within yourself there’s a good chance you’re going to catch them later.

MAARTEN SEGHERS: I think it’s something almost everyone has to work at. It’s no good for your ego if someone goes by and at that point you have the feeling that you can ride long. You have to learn that you can do it twice in a race, go a little bit too hard. But you can’t go too fast through the whole race,4 or 5 times.

My coach always says don’t burn all your matches. You can’t go full force all the way and then expect to run a good race.

BRAD BROWN: Have you done that? Gone full tilt on the bike and had nothing on the run?

Saving your legs on your Ironman bike

MAARTEN SEGHERS: I did that in Kona 2015. My Power meter didn’t work on the race. The first part of the race I went too fast. The bike leg was okay but the run wasn’t good stuff.

BRAD BROWN: It wasn’t pretty, I’m sure. As far as training goes, do you do most of your bike stuff indoor or outdoors? Do you do it alone, or in a group? What does training look like for Maarten Seghers?

The right mix to your Ironman bike training

MAARTEN SEGHERS: I’m  kind of a  freak in that area, I ride indoors. I don’t think there are many cyclists that like indoor training but I love it. Love riding indoors watching some series on TV and then 4 or 5 hours is no problem.

I keep making progress on the bike, but I keep training indoors. Sometimes I go outdoors. This winter I only trained twice outdoors. My biking is no problem doing that.

BRAD BROWN: You’re braver than me, Maarten. I must say, I cannot. It drives me mad sitting on an indoor trainer but I’m glad you can do it.

Your favourite workout, share with us your favourite workout on the indoor trainer.

MAARTEN SEGHERS: To be honest I have no problem training indoors. If the sun is out and it’s a beautiful day I prefer to go outdoors. The weather starts improving now in Belgium and then I prefer going outdoors.

Training your Ironman pace indoors

My favourite workout would be something like a 5-hour ride with 2 x brick sessions of 1-hour at Ironman pace. You start riding 1-hour relaxed, then an hour Ironman pace, half an hour relaxed, an hour Ironman pace, go right through to the end of your session. That’s a good session.

BRAD BROWN: Awesome. Looking at your bike over time, is there something you’ve done that’s given you big gains? You’re obviously riding with Power. Have you always ridden with Power? I think for most age groupers they’ll say a Power meter is a big thing. But is there anything else?

MAARTEN SEGHERS: About 4-years ago, I also started riding with a power crank system. I don’t know if you know it. The cranks are independent from each other. You have to pull your leg up each time. It teaches you to use your hamstrings as well. I don’t try to exaggerate it because it’s a hard training session. But I try to do it in the winter, once or twice in a week.

Build a strong base for your Ironman bike

BRAD BROWN: Just to build up that strength. And again, you talk about training through winter. It’s the consistency and training right the way through so that you’re not starting a new season on the back foot. You’ve got that base to build on.

MAARTEN SEGHERS: Yes. And also 2014 was my worst year. From then on I started training twice a week on core stability. It helped me in every area of triathlon. Helped me on the swim, the bike and the run and I didn’t have any more back problems. That’s also very important, I think.

Core strength will boost your triathlon performance

BRAD BROWN: That’s one thing a lot of triathletes neglect. They don’t worry about strength and conditioning. In a typical week for you, training wise, how many core sessions will you get in? What will the breakup be? You mentioned that you swim 4 times a week. How many times do you bike, and how many times do you run? Then how many strength and conditioning sessions?

MAARTEN SEGHERS: In a typical week, it’s 4 times spinning. Biking, it’s more about the kilometers. I start building up from 300 to 500 km. The run as well, it’s a build up from 40 km to now a little more than 80 km.

The core stability I do twice a week in the winter, an hour to an hour and a half. I’m now letting that go. Maybe this week I will do one half an hour but then I prefer relaxing a little bit more before my race. The core stability is now done for the race. It’s time to rest a little bit more. But in the winter it’s an hour and a half, twice a week.

Tapering: A key part of your Ironman training

BRAD BROWN: You mentioned you’ve got a race coming up. How do you deal with the taper? Are you one of those athletes that gets quite nervous and jittery? Do you feel like you should be doing more? Is it something you struggle with? Or are you quite comfortable with the taper, do you like it?

MAARTEN SEGHERS: I quite like it because I start to taper about 10 days before a race. The nervous feeling that the race needs to start, is only the day before. I think if you have some experience, you know that you have to do it. If you don’t do the taper you can’t do the race at your full potential. It’s part of the race. I think it’s normal that some athletes get nervous about it but you have to do it and you have to relax. Try to enjoy it.

BRAD BROWN: Maarten, we’ll get you on next time to talk about your run. Thank you  for your time today on The Kona Edge. Much appreciated.

MAARTEN SEGHERS: Thank you Brad.

About Us

Brad Brown is a 40 something age grouper that dreams of one day qualifying for and racing on the big island (He may have to outlive everyone in his age group though).

Morbidly obese in 2009, Brad clocked in at 165kgs (363lbs) at his heaviest.

He's subsequently lost a third of his body weight on the way to a half Ironman pb of 5:06 and a full Ironman pb of 12:21.


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