IRONMAN 70.3 Brasilia

Arrive early enough to settle your breathing before the start area gets crowded. Do a short, easy warm-up that keeps you feeling smooth rather than fatigued. Seed yourself with swimmers who match your intended effort so the first 5–10 minutes don’t become constant dodging. On the whistle, focus on clean stroke rhythm and a controlled start—your goal is to get to “comfortable hard,” not sprint the first length.

You’re covering 1768 m in freshwater where the temperature varies, so start a touch conservative and let your body warm into the effort. Expect some chop based on wind and surface conditions; keep your head position steady and steer with your shoulders so you don’t add extra distance. Aim to sight efficiently, especially if buoy turns pull you off-line. For nutrition, you generally won’t take much during the swim—just be ready to transition fast and start your planned hydration/fuel immediately on the bike.

Run/bike transition flow: after the swim, move quickly but safely through T1. Prioritize execution—rack the bike, secure helmet/glasses, tighten shoes, and take a breath before you clip in. As you leave the mount line, get your cadence settled and your power smooth right away; avoid the urge to surge until you’re confident you’re in the flow of the course. Mentally prep for rolling terrain: think “steady build” instead of “flat-road race.”

The bike is 89.4 km with 521 m of elevation gain on a rolling profile, so expect repeated surges and recoveries rather than one long climb. With wind around 3.5 m/s from the SE, plan to stay stable in your position—when the wind hits you, hold your line and avoid over-correcting; when it’s at your back/side, resist chasing speed with too high effort. Fueling target per hour is 90 g carbs, 1000 mg sodium, and about 800 ml fluid—start within the first section of the bike and stay consistent through the ride rather than waiting for later. Use the terrain to guide intensity: push a little harder on the uphills but protect your overall average power so the run doesn’t pay the bill. If heat is moderate (air temp roughly 18.3–25.9 C), keep sipping regularly—small, frequent intakes work best when the body starts to warm.

T2 from bike to run: rack time and transitions should be efficient, but don’t rush the first steps. Once you start the 21.2 km, treat the first few minutes like a controlled launch—your legs will feel heavy, and that’s normal after rolling 89.4 km. Get your breathing settled early, then gradually bring pace up once you’ve found rhythm. Mentally, expect the rolling profile to repeatedly change the feel of the ground; you’ll need to manage effort on the up/downs rather than forcing a flat-road pace.

You’ll run 21.2 km with 80 m elevation gain on a rolling course, so pacing discipline is the difference between a strong finish and a blow-up. In moderate heat (air temps roughly 18.3–25.9 C), keep your effort steady and let the rolling terrain shape your pace—slightly shorter steps and controlled cadence on climbs, longer but not forced strides on descents. Hydration and carbs should continue from the fueling plan you built on the bike; even if your legs are tired, keep taking fluids and eat/drink at aid stations so you don’t drift into under-fueled territory. Because you’ve already had wind exposure on the bike, focus on posture and cadence steadiness on the run—your body will want to tighten up when fatigue hits, and that’s where cadence management helps. If it feels like you’re working too hard early, that’s usually an intensity management issue, not a “fitness” issue—back off for the first segment and let the course come to you.