IRONMAN 70.3 Cartagena

Arrive early to get calm in the water and verify your line of sight for the first buoy. If you haven’t raced this type of start before, let your seeding do the work: start where you can hold your pace without sprinting for position. In the first few minutes, focus on a smooth, repeatable stroke and settle your breathing rhythm—don’t try to “win” the first 200–300 m; you’re setting up the back half.

You’re swimming 1,910 m in water that’s listed around 29.8°C and could be non-wetsuit—confirm the official wetsuit ruling on race morning in the IRONMAN athlete guide. Expect typical choppy-open-water behavior when wind is present; with a light-to-moderate NE wind, any cross-current or surface texture can pull you off line, so sight often and keep your path efficient. Pace to finish the second half controlled rather than fading in the last 200–300 m. Fuel isn’t the priority during the swim, but your goal is to exit with enough calm to absorb the transition and start the bike smoothly.

Plan a clean swim-to-bike flow: cap/goggles off, quick dry/strap up, then get into your cycling gear efficiently so you can start building power immediately. In T1, prioritize stability (shoe straps/alignment before you fully lock in), hydration access, and a smooth mount without “arm wrestling” the bike. The first 5–10 minutes should feel like controlled acceleration on rolling terrain—get your cadence comfortable and let your breathing settle.

The bike is 90.3 km with 422 m of total elevation on a rolling profile, so the best strategy is to ride the climbs with intent but avoid hammering the short gradients. With NE wind around 4.6 m/s, expect some variable resistance—don’t overreact with surges; instead, keep effort consistent and let speed fluctuate. Your fueling targets are 90 g carbs, 1,000 mg sodium, and about 800 ml fluid per hour—use the first hour to lock into your rhythm so you’re not behind later when heat rises. Because conditions are hot (air temps up to ~29.8°C), drink regularly even if you don’t feel thirsty, and aim to take in carbs and sodium continuously rather than “catching up” between aid moments. If the bike holds a rolling rhythm, use your power/effort to prevent flat-out efforts on the uphills that can’t be repaid on the later undulations.

T2 is where you set up the run pacing. Focus on getting off the bike and into an efficient cadence quickly: walk 10–20 seconds if you need to reset shoes, but don’t fully stop. The legs will feel “springy but heavy” in the first kilometer—think smooth turnover before pushing intensity. Start the first miles slightly controlled relative to how you feel; rolling terrain and heat will magnify mistakes.

You’ll run 21.2 km with 83 m of elevation on a rolling profile, so expect repeated small climbs and descents that can tempt you to speed up on the downs. With hot conditions (air temps roughly 24.9–29.8°C) and a steady NE wind, manage your effort to stay aerobic and avoid overheating—short surges on downhills can cost you later. Keep drinking and fueling continuously using your established targets; the goal is to remain on rhythm rather than waiting for “big” hits later. With your nutrition targets at 90 g carbs, 1,000 mg sodium, and ~800 ml fluid per hour, distribute intake across the run so you’re not spiking stomach load at any one time. If you feel your pace slipping, reduce intensity slightly before you completely drain—use the rolling profile to keep form smooth and stride efficient, especially as the heat builds.