IRONMAN 70.3 Mamaia

Get to the swim entry early and mentally commit to a calm first 5–10 minutes: find your rhythm, don’t chase people in the first strokes, and settle your breathing. If you’re near the front, stay controlled—sea starts can feel chaotic even with good seeding. Use the first section to establish a consistent stroke rate and sighting pattern for the course line; plan to relax your grip and keep your kick steady so you’re not overworking before the body settles.

You’ll swim 1,900 meters in sea water at around 22.5°C, where wetsuit use is expected to be legal, but confirm the official ruling on race morning in the IRONMAN athlete guide. With a sea venue, anticipate some chop and current variation, so keep your head position stable and sight frequently enough to stay on line without repeatedly “reaching.” The goal in this swim is clean, efficient propulsion—arrive at T1 composed rather than gasping, because the bike is flat/fast and you’ll want your legs fresh. Fueling during the swim is typically not practical; focus on hydration readiness (you should be able to start drinking at T1) and make sure you’re not under-breathing when you transition out of the water.

Your T1 should be practiced so you can quickly get from swim state to bike rhythm: prioritize getting shoes secured and your first pedal strokes smooth. As you mount, accelerate gently—don’t sprint the first meters—and let your breathing match your effort within the first few minutes. Have your first drink and fueling already planned so you can start consuming right away; on a fast course, delaying intake often turns into a late-race energy deficit.

The bike is 87 kilometers with 261 meters of elevation gain and a flat/fast profile—perfect for building a steady, aerodynamic effort rather than “spiking” power. You’ll ride in wind conditions of about 6.6 m/s from the NE, so expect the headwind/tailwind pattern to change where you’re exposed; ride a little lower and quieter into wind to protect speed and save energy. Aim for consistent power and smooth cadence; if gusts rise, resist surging—stay composed and let your speed fluctuate. For fueling, target 90 g carbs per hour, 750 mg sodium per hour, and about 650 ml fluid per hour: start early (within the first part of the ride) and keep intake regular rather than trying to catch up later. On a flat course, this is where you lock in your nutrition cadence while using the wind to your advantage—draft where allowed, and on exposed sections, stay stable in your aero position and avoid abrupt steering corrections.

T2 is about rebuilding leg feel: first steps off the bike often feel heavy and slightly “springless,” so keep your first 1–2 kilometers controlled. Get your cadence up quickly with shorter steps, and focus on relaxed shoulders and steady breathing rather than sprinting the first straight. Before you settle into race pace, take in your first run drink quickly so you’re already hydrated before you feel thirsty.

The run is 20.3 kilometers with 25 meters elevation gain and a flat/fast profile, which means the main battle is managing effort as the race gets quick. Conditions are typically moderate heat with air temperatures that can be around the 15–21.1°C range, so you should be able to run strong without needing to radically slow down—just don’t overestimate how easy the early kilometers feel. With the same NE wind influencing the course, expect it to feel stronger on exposed portions; use it as a pacing tool (hold your effort when wind is unfavorable and don’t chase pace when you’re getting pushed around). Nutrition should continue from the bike plan—if you’ve been hitting 90 g carbs/hour on the bike, keep the transition smooth so you don’t arrive with a fuel gap. Aim to drink consistently and avoid “chasing” thirst with big intakes late—small, regular sips keep performance stable. Since the course is flat, your form matters: keep strides smooth and efficient as fatigue accumulates, and protect your cadence from dropping in the final third.