IRONMAN 70.3 Swansea

Arrive with a quick, easy warm-up (aerobic swim or a short jog-in) so your first strokes feel smooth. Seed yourself honestly based on your swim pace and choose space that reduces crowding; in a wetsuit-legal race start, a controlled first 50–200 m matters more than going hard early. When the horn goes, focus on clean, repeatable breathing and settle into a comfortable rhythm right away—avoid sprinting to “get clear,” then scrambling later.

You’ll cover 1.91 km in 19.1°C water—most athletes should feel stable in a wetsuit and can stay efficient with a steady cadence. Because the start can be congested, your job is to hold position for the first chunk, then gradually move into clear water without spiking effort. Plan to breathe consistently and keep your stroke long enough to avoid unnecessary churn; any extra turbulence early will cost you energy you need for the bike climb segments. If conditions create chop, shorten your “panic” moments: stay relaxed in the shoulders, keep a steady sighting rhythm, and prioritize smooth propulsion over forcing speed. Fueling happens after the swim—on the swim itself, do not count on taking in carbs or fluids unless your race protocol explicitly supports it (most athletes won’t).

Think transition flow: as you exit the swim, aim to get organized early—shoes on the correct feet, helmet fastened properly, and bike shoes secured before you start pedaling. As soon as you mount, do not chase speed immediately; settle into a steady cadence and let your legs “find temperature.” With a hilly/climbing 89.9 km course and 819 m of gain, the first 15–20 minutes are where you set the tone—smooth power, controlled heart rate, and no hero climbs yet.

The 89.9 km bike is hilly with 819 m of elevation gain, so plan for a pacing strategy that saves you for the repeated climbing moments rather than one big push. There’s a west wind at 5.2 m/s, which can subtly affect speed and comfort; expect that headwind/sidewind sections will feel harder, so ride by effort rather than staring at numbers. Use gear changes early on climbs—keep cadence from dropping too low—then recover on the downs without standing and sprinting unless it’s part of your plan. Fueling targets should be consistent: take in about 90 g carbs and 750 mg sodium per hour, along with roughly 650 ml fluid per hour, adjusting for how much you’re sweating. Aim to take your nutrition in small, repeatable doses throughout the ride, not all at once; this helps the climbs go down easier and supports the run. Because heat is only moderate (air temp roughly 13.7–21.2°C), you still need fluids—cooler starts often trick athletes into under-drinking until later.

On the bike→run transition (T2), expect your legs to feel a little heavy for the first few minutes—this is normal after 89.9 km of climbing. Start the run slightly conservative and let the rhythm build; you’re looking for controlled breathing and quick turnover, not a fast first kilometer. Use transition discipline: grab what you need, don’t fumble your first steps, and commit to an easy-to-strong ramp during the opening flat sections.

The run is 21.2 km and flat/fast with only 25 m of elevation gain, so the temptation is to go hard early. Instead, lock into an effort that matches your fueling and hydration state from the bike; with moderate heat and a west wind around 5.2 m/s, you may feel periodic changes in comfort—ride your pace, not the weather. Keep your stride efficient and slightly shorter than on your track workouts; after the bike, that’s usually the fastest way to avoid early calf fatigue. Continue drinking and fueling by schedule; the primary targets provided (90 g carbs/hour, 750 mg sodium/hour, ~650 ml fluid/hour) should guide your run intake to prevent late-race slowdown. Even in moderate temperatures, don’t wait for thirst—use consistent sips and planned gel/food timing so the flat course stays “fast-friendly” rather than punishing.