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IRONMAN

IRONMAN World Championship

Saturday, 10 October 2026

IRONMAN World Championship is a long-course triathlon defined by a 3.883 km freshwater swim, an 181 km rolling 1027 m-gain bike into a hot race-day run (42.2 km).

Air
23–27°
typical
Wind
3.3 W
prevailing
Water
typical — confirm
Bike climb
+1027 m
Fueling — per hour
90 g
carbs
1000 mg
sodium
800 ml
fluid
Baseline for a ~12 h finish, 70 kg athlete, hot conditions.

Typical 10-year conditions, not a forecast. Water temperature and the wetsuit ruling are set on race morning — check the IRONMAN race guide →

Worlds qualification — slots TBAsee who qualified →
0 km91 km181 km189 m
181.0 km · +1027 m climbing
T1 — swim to bike

Treat T1 as a system: exit the swim, get your kit on efficiently, and transition your breathing from “swim effort” to “bike cadence.” After you mount (transition logistics follow the course layout and athlete markings), take the first few minutes to find your preferred cadence and settle into your power/speed plan rather than reacting to other riders. Start slightly restrained for the first segment so your legs are not overloaded before the rolling profile shows itself.

During the bike

You’ll ride 181 km over a rolling course with 1027 m of elevation gain, which means repeated changes in demand—stay patient over the rises and focus on steady output through the flatter/descending sections. Wind is from the W at about 3.3 m/s, so plan for small speed/effort swings: expect a touch more effort on the parts where you’re working into it and be careful not to overcook the legs when it shifts behind you. In hot conditions (air temps around 23 to 27.4 C), prioritize keeping your hydration consistent rather than waiting until you feel thirsty. Your fueling target during the bike is 90 g carbs per hour, 1000 mg sodium per hour, and about 800 ml fluid per hour—start early, keep it regular, and don’t stack large gulps only when you’re already behind.

Closing notes

The race on a rolling bike is consistency—use the climbs to stay controlled and the flats/descents to stabilize effort, then fuel on schedule.

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Weather is a 10-year climatology (typical, not a forecast). Course tracks are approximate, derived for planning — verify against the official course. Maps © OpenStreetMap. Not affiliated with or endorsed by the IRONMAN Group.