Preparation guide · IRONMAN World Championship Kona
Ironman Kona 2027: how to prepare it and what to eat and drink on the bike and run
The next edition is on Saturday 9 October 2027 (provisional date: the organisers haven't confirmed it yet; in 2026 it was held on 10 October. The time of each leg is indicative. You have to qualify to race it), starting in Kailua Pier (Kona, Hawaii, USA) at 6:50. Here you have the three legs of the Ironman World Championship Kona: the swim, the bike with its profile and feed stations, and the run with split times, what's at each aid station, how much to eat and drink and the usual weather.
Swim (3.8 km): the swim
Kailua Bay, start at Kailua Pier (official 2024 GPX; compare with the 2026 map); no in-water station confirmed.
Swim keys
- 3.8 km in Kailua Bay, starting from Kailua Pier on an out-and-back course marked by buoys. The water is very clear and warm, but the swell counts: practise navigating in open water.
- It's a mass start with lots of people: position yourself outside the most direct line if you aren't among the fastest and avoid swimming over others.
- Compare the official 2024 GPX with the 2026 map before the day: the course may vary.
Bike (180 km): route and profile
Official 2024 GPX: Queen Ka'ahumanu to Hawi and back; B1–B10 aid stations from the official 2025 guide, kilometres not confirmed for 2026.
The climbs and key sections, one by one
| Climb or section | Length | What it's like and how to ride it |
|---|---|---|
| 1. Kailua-Kona and Palani km 0 | 12 km | Opening loop through town, with the Palani Road climb up to the Queen K and big crowds. With the adrenaline of the swim everyone goes off hard: you, at 65–70 % of FTP. Drink at the very first station. |
| 2. Queen K to Kawaihae km 12 | 58 km | Highway across the black lava fields, with long rollers, heat rising off the asphalt and shifting winds. Aero and steady watts, no surges on the rollers. Douse yourself at every station and start on salt now. |
| 3. Climb to Hawi km 70 | 22 km avg 1.9 % | A long, gradual climb from Kawaihae to the turnaround in Hawi, with the famous cross and headwinds. Don't fight the wind: same watts, whatever speed results. Firm grip in the gusts and off the aero bars if they push you around. Special needs bag at Hawi if you use one. |
| 4. Descent from Hawi km 92 | 23 km | A fast descent towards Kawaihae, with dangerous side gusts. Hands on the hoods and no risks. Eat here: it's the easiest stretch of the day. |
| 5. Back along the Queen K km 115 | 65.6 km | Back to Kailua across the lava in the hottest hours, often into a headwind. The part that decides the marathon: hold your watts, drink at every station and keep up carbs and salt until km 170. |
Route keys
- 180 km along the Queen Ka'ahumanu Highway to Hawi and back: little climbing (the track measures about 800 m), but the heat, humidity and wind make this one of the toughest bikes. Don't play with the watts early on.
- There are ten stations (B1 to B10) at km 24.5, 47.3, 60.5, 71.3, 85.9, 95.6, 119.6, 136.8, 157.1 and 166.4, with water, Mortal Hydration, cola, bananas, chips and Maurten gels and bars. The kilometres are from the 2025 guide.
- In extreme heat, drink at every station and wet yourself: water over your helmet and body. Salt and electrolytes matter as much as carbs.
- The crosswind on the stretch towards Hawi is famous: grip the handlebars firmly and don't rely on the aero position during gusts.
3 more keys in WinWatts: with the forecast for the days before, the wind and heat section by section, and on which climbs to eat and drink.
Bike (180 km): what to eat and drink
How much a typical rider (72 kg) needs depending on their time. From 2–3 hours on, what matters most is eating carbs regularly (every 20–30 minutes) and drinking before you're thirsty.
| Total time | Carbs per hour | Total carbs | Drink per hour | Total drink | Sodium per hour |
|---|---|---|---|---|---|
| 5 h 15 | 75 g/h | 330 g | 750 ml/h | 3.9 l | 800 mg/h |
| 6 h | 75 g/h | 365 g | 750 ml/h | 4.5 l | 800 mg/h |
| 6 h 45 | 75 g/h | 440 g | 750 ml/h | 5.1 l | 800 mg/h |
| 7 h 30 | 75 g/h | 475 g | 750 ml/h | 5.6 l | 800 mg/h |
More than 60–90 g of carbs per hour only if you've trained it. Don't try on race day what you haven't tolerated in training.
Section by section between feed stations (for about 6 h)
At the feed stations (km 24, 47, 60, 71, 86, 96, 120, 137, 157, 166) you stop, eat something and refill your bottles. But what matters most is what you take on the move until the next one: this table tells you how much. You can pick it up at the station or carry your own gels and bars; what matters is spreading it out, not eating it all at once when you stop.
| Section | Duration | Carbs to take in the section | Drink in the section |
|---|---|---|---|
| km 0 → 24 | 0 h 54 | 65 g | 650 ml |
| km 24 → 47 | 0 h 43 | 55 g | 550 ml |
| km 47 → 60 | 0 h 25 | 30 g | 300 ml |
| km 60 → 71 | 0 h 24 | 30 g | 300 ml |
| km 71 → 86 | 0 h 29 | 35 g | 350 ml |
| km 86 → 96 | 0 h 28 | 35 g | 350 ml |
| km 96 → 120 | 0 h 40 | 50 g | 500 ml |
| km 120 → 137 | 0 h 35 | 45 g | 450 ml |
| km 137 → 157 | 0 h 43 | 55 g | 550 ml |
| km 157 → 166 | 0 h 17 | 20 g | 200 ml |
| km 166 → 180 | 0 h 22 | 25 g | 250 ml |
The key section is the first one: there's no feed station until km 24, so you leave Kailua Pier with full bottles and about 65 g of carbs on you (for example, 2 gels).
Not going to take 6 h? In WinWatts you set your target time and the feed stations, and you see these sections with your real pace on each climb. You can also compare scenarios: what changes if you go faster or slower.
Bike (180 km): weather in mid-October
What the weather was like on race day in recent editions (in Kona):
| Year | Low | High | Rain | Max wind |
|---|---|---|---|---|
| 2022 | 26 ºC | 29 ºC | 1.4 mm | 13 km/h |
| 2023 | 24 ºC | 29 ºC | 0.5 mm | 12 km/h |
| 2024 | 24 ºC | 29 ºC | 0.0 mm | 9 km/h |
| 2025 | 26 ºC | 30 ºC | 0.7 mm | 18 km/h |
| 2026 | 26 ºC | 31 ºC | 0.4 mm | 10 km/h |
Run (42.195 km): route and profile
Official 2024 GPX (Ali'i Drive and Energy Lab); 24 stations R1–R24 from the official 2025 guide, kilometres not confirmed for 2026.
Climbs and descents
Sections of at least 400 m with a grade over 1.5 %, and how much a typical runner's pace changes at the same effort. Run by feel (or heart rate), not by watch pace.
| Section | Grade | At the same effort |
|---|---|---|
| km 11.3–12.1 | 4.0 % | +47 s/km |
| km 12.3–13.2 | -2.6 % | -21 s/km |
| km 19.3–20.3 | 1.5 % | +16 s/km |
| km 27.2–28.6 | 2.0 % | +22 s/km |
| km 32.0–32.9 | -1.5 % | -14 s/km |
| km 39.0–40.0 | 2.4 % | +27 s/km |
| km 40.1–40.9 | -3.9 % | -29 s/km |
The course, section by section
| Section | Length | What it's like and how to run it |
|---|---|---|
| 1. Ali'i Drive (out and back) km 0 | 16 km | Out and back by the sea along Ali'i Drive, with some shade, high humidity and crowds. Start slower than you think: 10–20 s/km below your target pace. Ice and water at every station from the first one. |
| 2. Palani Road km 16 | 1.5 km | A short, steep climb from town up to the Queen K. Short steps or power-walking: nothing to gain here and a lot to lose. |
| 3. Queen K to the Energy Lab km 17.5 | 7.5 km | Open highway across the lava, no shade and reflected heat. Go station to station: drink, douse yourself and ice in your cap. Pace by heart rate. |
| 4. Energy Lab (NELHA) km 25 | 6 km | Down to the sea and back up to the Queen K: the hottest, loneliest stretch of the marathon. This is where it's all decided: cola and broth if you tolerate them, plenty of ice and walk the stations without guilt. |
| 5. Back along the Queen K km 31 | 9 km | The long kilometres back to Kailua, with the sun going down. Split it into stations (one every 1.5 km) and don't calculate times. |
| 6. Down Palani and finish on Ali'i Drive km 40 | 2.2 km | Down Palani and the last metres along Ali'i Drive, to the most famous finish line in triathlon. Enjoy it: you've earned it. |
Route keys
- A marathon with 24 stations (R1 to R24) along Ali'i Drive and the Energy Lab, with water, Mortal Hydration, cola, Maurten, fruit, chips and broth at each. Use them all: it's the heat, not the hills, that decides here.
- The Energy Lab is an out-and-back stretch on a road beside the lava, with no shade and a lot of reflected heat. It's where you see who has eaten and drunk well on the bike: don't take it on without ice or water to wet yourself.
- At each station drink, wet yourself and grab ice: in your kit, under the cap and in your hands. Walking a few metres at the station isn't losing time.
- The station kilometres are from 2025: check the 2026 map before the day. Adjust your gel plan to the organisers' and carry your own if the brand doesn't sit well.
1 more keys in WinWatts: with the forecast for the days before, the wind and heat, and your split times at your pace.
Split times
At the same effort: a bit slower on the climbs and faster on the descents, as each section's average pace shows, with the clock time counted from when you start running (indicative: it depends on how long you take to swim and ride). You start with the bike in your legs: begin below your clean marathon pace. Write yours down or wear them on a pace band: watch GPS usually reads long.
| Point | 3 h 30 | 4 h 15 | 5 h | 6 h |
|---|---|---|---|---|
| Average pace | 4:59 /km | 6:03 /km | 7:07 /km | 8:32 /km |
| km 5 | 0:24:52 14:54 | 0:30:12 15:00 | 0:35:32 15:05 | 0:42:38 15:12 |
| km 10 | 0:49:44 15:19 | 1:00:24 15:30 | 1:11:03 15:41 | 1:25:16 15:55 |
| km 15 | 1:14:57 15:44 | 1:31:00 16:01 | 1:47:04 16:17 | 2:08:29 16:38 |
| km 20 | 1:39:55 16:09 | 2:01:20 16:31 | 2:22:44 16:52 | 2:51:17 17:21 |
| Halfway | 1:45:28 16:15 | 2:08:04 16:38 | 2:30:41 17:00 | 3:00:49 17:30 |
| km 25 | 2:04:26 16:34 | 2:31:06 17:01 | 2:57:46 17:27 | 3:33:19 18:03 |
| km 30 | 2:29:48 16:59 | 3:01:54 17:31 | 3:34:00 18:04 | 4:16:48 18:46 |
| km 35 | 2:54:24 17:24 | 3:31:47 18:01 | 4:09:09 18:39 | 4:58:59 19:28 |
| km 40 | 3:19:34 17:49 | 4:02:20 18:32 | 4:45:05 19:15 | 5:42:06 20:12 |
| Finish | 3:30:00 18:00 | 4:15:00 18:45 | 5:00:00 19:30 | 6:00:00 20:30 |
Aid stations: what's there and how much to drink
For a typical runner finishing in about 4 h 15: sip without stopping and take each gel just before an aid station, to wash it down with water. The organisers hand out gels at km 2.1, 3.9, 5.6, 6.3, 8, 9.8, 11.9, 13.5, 15.8, 18, 19.5, 20.9, 22.4, 23.7, 25.3, 27, 28.6, 30.1, 31.7, 33.2, 34.6, 36.9, 39.1 and 40.4: if they match your plan, those are gels you don't need to carry.
| Where | What's there | Time (for 4 h 15) | You |
|---|---|---|---|
| km 2.1 | water, sports drink, cola, gels, fruit, solid food | 14:43 | ~200 ml |
| km 3.9 | water, sports drink, cola, gels, fruit, solid food | 14:54 | ~150 ml |
| km 5.6 | water, sports drink, cola, gels, fruit, solid food | 15:04 | ~150 ml |
| km 6.3 | water, sports drink, cola, gels, fruit, solid food | 15:08 | ~100 ml |
| km 8.0 | water, sports drink, cola, gels, fruit, solid food | 15:18 | ~150 ml · gel: theirs or yours |
| km 9.8 | water, sports drink, cola, gels, fruit, solid food | 15:29 | ~150 ml |
| km 11.9 | water, sports drink, cola, gels, fruit, solid food | 15:42 | ~200 ml · gel: theirs or yours |
| km 13.5 | water, sports drink, cola, gels, fruit, solid food | 15:52 | ~150 ml |
| km 15.8 | water, sports drink, cola, gels, fruit, solid food | 16:06 | ~200 ml |
| km 18.0 | water, sports drink, cola, gels, fruit, solid food | 16:19 | ~200 ml · gel: theirs or yours |
| km 19.5 | water, sports drink, cola, gels, fruit, solid food | 16:28 | ~100 ml |
| km 20.9 | water, sports drink, cola, gels, fruit, solid food | 16:37 | ~100 ml |
| km 22.4 | water, sports drink, cola, gels, fruit, solid food | 16:46 | ~100 ml |
| km 23.7 | water, sports drink, cola, gels, fruit, solid food | 16:53 | ~100 ml · gel just before |
| km 25.3 | water, sports drink, cola, gels, fruit, solid food | 17:03 | ~150 ml |
| km 27.0 | water, sports drink, cola, gels, fruit, solid food | 17:13 | ~150 ml |
| km 28.6 | water, sports drink, cola, gels, fruit, solid food | 17:23 | ~150 ml |
| km 30.1 | water, sports drink, cola, gels, fruit, solid food | 17:33 | ~150 ml · gel: theirs or yours |
| km 31.7 | water, sports drink, cola, gels, fruit, solid food | 17:42 | ~150 ml |
| km 33.2 | water, sports drink, cola, gels, fruit, solid food | 17:51 | ~100 ml |
| km 34.6 | water, sports drink, cola, gels, fruit, solid food | 17:59 | ~100 ml · gel just before |
| km 36.9 | water, sports drink, cola, gels, fruit, solid food | 18:13 | ~200 ml |
| km 39.1 | water, sports drink, cola, gels, fruit, solid food | 18:26 | ~200 ml |
| km 40.4 | water, sports drink, cola, gels, fruit, solid food | 18:34 | ~100 ml |
How many gels and how much to drink
What a typical runner (68 kg) needs depending on their time, with 35 g gels. When running the stomach tolerates less than on the bike: more than 60 g of carbs per hour only if you've trained it. Gels alone don't reach that figure (the first one comes around 45 minutes and none are due in the last half hour): the rest comes from drinking sports drink instead of water at a few aid stations.
| Time | Carbs per hour | Gels | Total drink | Sodium per hour |
|---|---|---|---|---|
| 3 h 30 | 60 g/h | 5 × 35 g | 2.8 l | 800 mg/h |
| 4 h 15 | 60 g/h | 6 × 35 g | 3.4 l | 800 mg/h |
| 5 h | 60 g/h | 7 × 35 g | 4.0 l | 600 mg/h |
| 6 h | 60 g/h | 9 × 35 g | 4.8 l | 600 mg/h |
Nothing new on race day: gels, breakfast, shoes and socks, all tested on your long runs. Vaseline on your feet, groin and armpits, and protect your nipples. If it's cold at the start, wait in your corral in old clothes you can throw away.
Run (42.195 km): weather in mid-October
What the weather was like on race day in recent editions (in Kona):
| Year | Low | High | Rain | Max wind |
|---|---|---|---|---|
| 2022 | 26 ºC | 27 ºC | 0.3 mm | 8 km/h |
| 2023 | 25 ºC | 26 ºC | 0.7 mm | 9 km/h |
| 2024 | 25 ºC | 26 ºC | 0.0 mm | 8 km/h |
| 2025 | 25 ºC | 27 ºC | 0.2 mm | 10 km/h |
| 2026 | 27 ºC | 30 ºC | 1.1 mm | 8 km/h |
When running, heat slows you down: allow roughly 2 % more time for every 5 ºC above 12 ºC.
Your Ironman World Championship Kona, tailored to you
This guide uses a typical triathlete. In WinWatts we calculate it with your data:
- Your time on each leg, from your FTP and pace, and your finish time.
- The race-day forecast and what to wear on the bike and on the run.
- Your food and drink plan for the bike and the run, with your gels, bars and bottles.
- Your training plan until Saturday 9 October 2027, adjusted every week to how you're doing.
WinWatts is not affiliated with the organisers of the Ironman World Championship Kona. Dates, routes, schedules and registration: official website. Official 2024 tracks; aid stations from the official 2025 athlete guide (kilometres not confirmed for 2026); official 2026 maps; weather from past editions (Open-Meteo). For guidance only: it doesn't replace advice from a health professional.