I started training for my first Ironman in October 2025. I signed up for Oceanside 70.3 with little swimming experience, city cycling as my base, and a Chicago Marathon finish under my belt. Here's everything I learned.
My training was sporadic at first with no real structure. In January, I bought a generic $20 training plan from TrainingPeaks — one that wasn't tailored to me at all — and followed it roughly 90% of the time. Looking back, the one thing I wish I had done differently was spend more time on brick sessions and longer runs instead of worrying so much about the swim. The swimming portion ended up being far easier than I expected.
I rented a wetsuit and did two open water swims in a lake in California. My first swim, I was terrified. I hadn't put the wetsuit on properly, so I basically freaked out after 300 yards. After watching a couple of videos on how to do it correctly, the difference in range of motion and comfort was significant.
The swim took me 45 minutes. It would have been faster had my cheap Amazon goggles not kept fogging up, and had I swum closer to the buoys and sighted more efficiently. There wasn't nearly as much kicking and punching as I'd been led to believe — though maybe that's because I was so far to the right I was subconsciously dodging everyone.
Transition took me about 11 minutes — looking back, I could have cut that in half. It's a long run from the swim exit to the bike area. I rinsed the salt water off my face, but I was chafing badly on the back of my neck from the wetsuit. I also put on a jersey to carry my fuel and repair kit in case of a flat.
Cycling is my strongest discipline. Living in Northern California gave me plenty of hill training at elevation, and I really enjoyed the course through Camp Pendleton. One thing that became obvious early: just because someone buys a $10,000 bike doesn't mean they'll get a $10,000 result.
I kept my cadence in the 80–90 RPM range throughout the ride, which felt sustainable, and aero bars made a significant difference in comfort over the 56 miles. That said, I went a little too hard on the bike — and when it came to the run, I bonked around mile three and went to a very dark place for the remainder of the race.
My fueling was on point up until about mile 10 on the run — at that point, I was eating every banana and orange slice I could find. I also peed seven times from the swim through the run, so it's possible I over-hydrated.
The last half mile I was running through a wall — but the crowd support gave me a real boost of adrenaline. Seeing my girlfriend and her brother going absolutely crazy as I crossed the finish line was one of the greatest feelings I've ever had.
Don't stress the swim.Focus on brick sessions and put a real emphasis on the run. It is the hardest and most taxing portion on your body.
Nail your nutrition.Have a plan and stick to it well past the halfway point. Don't wait until you're in a dark place to start fueling.
Prioritize recovery.If your device is telling you that you need to recover — recover. It's not optional.
All in all, I would absolutely do another 70.3. And without a doubt, I want to complete a full Ironman — with at least 10 months of structured training behind me. Knowing what I know now, I'd spend less time stressing about race day and more time locked in on the training plan, working with a coach to build something tailored specifically to my capabilities and goals.
Bloodwork, training, and what's actually moving the needle. Written for athletes who want to understand their body, not just work it harder.