The Iron Century

33,900km. New York and back. That’s the distance Debi Hazelden and John Mergler will…

33,900km. New York and back. That’s the distance Debi Hazelden and John Mergler will cover between them in a feat they’ve named Iron Century. This Sydney-based duo are set to complete 100 Iron distance triathlons in 100 days to raise critical funds for Australian Red Cross. These two experienced athletes talk to 220 Triathlon about their preparation before they kick things off

John: I’ve had this idea of doing 100 Ironman-length triathlons in 100 days in my mind for a few years as a test of the ultimate endurance. I’ve been involved with triathlon for 35 years, and raced at Kona a dozen times in those years. After James ‘Iron Cowboy’ Lawrence did 50 Ironman distance races in 50 US states in 50 days, I thought ‘now’s the time’. So, starting on 28th January, I’ll be doing 100 Ironman distance races in 100 days, and Debi will do 100 half-Ironman distance races. Our final few days will be in Port Macquarie ahead of Ironman Australia, but primarily we’ll be swimming in City of Sydney pools, then transitioning to Centennial Park for the bike and run legs of Iron Century.
That’s not the only challenge, as our main goal is to raise $100,000 for Red Cross Australia. They do fantastic work in the Asia Pacific region, providing food and shelter to regions that have been devastated by natural disasters. They also work in the background with policy and education.

Debi: We’re both doing everything we can to make Ironman Australia a success as we both want to qualify for Kona — I’m determined to get to Hawaii for the second time after my debut in 2014, and I have a few Ironmans, an Everesting, and an Ultraman under my belt. And, on 7th May I’ll have completed 99 half-iron distances! Iron Century is really about endurance rather than speed, otherwise we risk injury.

John: Debi and I already have the body conditioning to go great distances. What our training is about now is building strength and endurance. The volume of training and the distances we’re doing isn’t much different to what we’d normally do. If I was training for a single Ironman, 30 percent of that volume would be at an intensity which would get me race ready. So, I’m substituting that 30 percent for more volume. Ultimately, I’m training for four or five hours every day, across different disciplines.

Debi: A lot of what we’re doing in the lead up and during Iron Century is injury management, and that comes down to having the right equipment, body efficiency and ergonomics.

John: In the swim you have to rely on good form. On the bike the key factor is having the perfect bike fit — I’m going to be on it for six hours a day, Debi three, so the bike and body have to become one organism.

Debi: And the right knicks are essential! Any form of chafing or saddle sores could ruin the whole thing. We’ve found that SCODY gear works exceptionally well for us.

John: We’ve really got to be honest with ourselves and monitor how we’re feeling at all times, and having contingencies in place for the onset of repetitive strain. So, for that, we’ll have dry needling, massage, and we’ll have to take anti inflammatories at some point. Nipping it in the bud is key. Where strain can come to a head each day is on the run. You’re a naked athlete in that you’re not supported by water, or a bike, you are fighting gravity all the time — I’m a huge fan of Hokas. These shoes are incredibly cushioned, lightweight, and performance oriented, and they’ll get us through the marathon everyday.

Debi: Our schedule is built so that we can do it at the right pace. Part of what I’m doing involves looking after our six-month-old son, Ryder, and organising the event. John’s out for 12-plus hours a day, but he has enough speed to allow himself enough recovery in between days.

John: I’ll be home by 7pm, have a 40 minute massage, a decent meal, time with Ryder, then go to bed! I’ll sleep for nine or ten hours to be at my best.

Debi: Our diet’s straightforward too — coffee before we start at 7am, buckwheat and steel cut oats with Chobani and berries after the swim. We’ve both found that raw food bars are easy to digest while on the bike. I’ll push on the cycle with minimal or no breaks, though John will stop for a meal after 90 minutes or so. Then the rest of the ride is an opportunity to fuel up, and prepare for the run where we’ll have mostly fluid nutrition. At the end of the day we’ll eat a full, proper meal. I reckon we would have earned it too!

John: We’re doing all of this in a controlled environment. At 6am, we’re in the safety of the fantastic pools in Sydney and the bike and the run are in Centennial Park. There are no traffic lights, and it’s quiet with very few cars and bikes — we’re not battling the streets. On the run I’ll be on the dirt of the park’s inside track, so there’s a soft landing for our feet. I have no doubt that the first ten days will be the hardest, getting into the rhythm, having the body adjust to that framework every single day. I did a trial recently where my heartrate was at 148bpm at 4:52 per km, which is comfortable. That’s right in my fat burning zone, hardly touched at all aerobically, and I’m at my most efficient. You want to go the distance? Learn to be efficient!

Debi and John encourage anyone who is racing at Ironman Australia to take part in Iron Century and raise funds for the Red Cross on their road to Ironman Australia 2017. Visit and join them in the pools, or on the bike or run — or all three! They would like to thank their sponsors: Ribble Cycles, SCODY, Hoka One One, Suunto, Lake Cycling, POC Sports, Thule, Quarq, Chobani, City of Sydney, Belgravia Leisure and Kustom Caps.

Instagram: @ironcentury
Facebook: @100ironman100days
Website: (we’ll be adding a daily/weekly blog and live tracking throughout the 100 days)