IRONMAN 70.3 · Vichy · 22 Aug 2027
How to train for IRONMAN 70.3 Vichy
The organiser's slogan for Vichy is swim, bike, run, relax, in the Queen of the Spa Towns. Riders read the bike page and plan the relaxing for the second half of the loop. The road climbs to La Guillermie, the organiser promises a fast, smooth return to town, and the sensible-sounding plan is to survive the climb and win the time back on the way down.
The numbers say the opposite. The way down gives back very little. The 22 km of climbing before the top of the bike take a Trained athlete more than a third of the bike leg, and they hold more than half of the gap between the Trained and Competitive bands. Vichy is decided going up, at a steady number, and the fast road home only reports how well you did it.
By Kian Briel, founder. Analysed by engine 1, updated
What is actually on the road
The organiser's own course files, drawn the way the Event Analyzer draws a member's race.
- Swim1.9 kmDistance only
- Bike90.4 km892 m upCourse file
- Run21 km106 m upCourse file
The swim is one loop of 1.9 km in the calm water of the Allier, started in the first light of the morning. The only water temperature the organiser publishes is 25 C, from 2024.
The bike is a single loop of 90.4 km with 892 m of climbing. It leaves along the lake past Bellerive, then crosses the Limagne plain, which the organiser calls the place to settle into the aero position. Road chicanes in Puy-Guillaume lead into the Livradois-Forez and the village of Châteldon. Then the climb to La Guillermie, shaded and full of switchbacks, with the Limagne plain and the Chaîne des Puys behind you at the top. From there a two-part descent drops to Ferrières-sur-Sichon. Fast descents with a few technical sections carry you on to Arronnes, and a long false flat follows the Sichon River down to Cusset. A careful descent on the Route de Creuzier brings you back to transition.
In the file, the first 23.6 km are one flat segment. The profile then rises almost without a break from kilometre 31 to kilometre 53, where it sits 475 m above the start. After that it loses all of it in the last 37 km.
The run is two loops of the Lac d'Allier and the town's parks, 106 m across 21 km, passing through the arena each time and finishing inside it. Each loop has one short drop of 4.7 percent in the file and nothing else.
Course shape by distance
- Flat 81%
- Climbing 10%
- Descending 10%
The longest stretches
- Bike, flat23.6 km24% of the bike
- Bike, climbing0.22 km1% of the bike
- Run, flat10.1 km48% of the run
Each row is one unbroken stretch of the course that keeps the same shape the whole way. The number is how much of that leg you spend inside it, and it comes out the same whether you are fast or slow.
What this course asks of each leg
Twelve training dimensions scored for each leg against its own course, the way the Event Analyzer scores a member's race.
Aerobic endurance first, muscular endurance a point behind it, both on the bike. The demand model scores them 85 and 82 there, threshold capacity 70 and both durability scores 67. The bike fills 54 percent of a Trained athlete's day, so the eight largest demands on the course are all bike demands before the run's aerobic endurance appears in ninth place. The swim's pair reads 85 and 80 and sits well down the list.
Three bike scores explain the terrain. High-intensity capacity reads 58 against 40 on the run and the swim. Strength and force reads 52. Technical skill reads 47, the switchbacks, the chicanes and the descents off the top showing up in one number. Feed the bike file to the engine and ask for a session, and it hands back twelve surges of three quarters of a minute in Zone 5 with three quarters of a minute easy between them. The climb's upper half has exactly that rhythm, with four ramps of 6 percent or steeper inside the last 5 km to the top.
The bands put a clock on it. A Trained athlete swims 38:12, rides 3:16:30 at 182 W and runs 1:59:11, for 6:03:53. The Competitive band finishes in 5:13:23 from 4.15 W/kg at 75 kg, 27 minutes faster on the bike and 18 faster on the run.
August here does not pick one temperature. In 2024 the organiser logged a low of 8 C and a high of 28 C. In 2026 it was 12 C and 25 C. You start in the cool of the sunrise and run in whatever the rest of the day brings.
- Aerobic endurance85
- Muscular endurance80
- Threshold capacity70
- Aerobic durability65
- Threshold durability65
- Fueling resilience55
- Technical skill55
- High-intensity capacity40
- Anaerobic capacity25
- Strength / force20
- Environmental resilience15
- Sprint power5
Nymiva reads what you can already show, from your own data
Connect your training history and the Focus Lab scores the same twelve dimensions this course demands against where you sit today. The gap between the two is what you train.
- MeasuredFrom your thresholds and testsThreshold power, threshold pace, critical swim speed and field tests you have done. The dimensions they can carry are scored directly.
- EstimatedFrom your training historyConnected activities are read for what they prove: long efforts, late-session fade, repeated hard work, fueling on long days. Each score says how it was read.
- ProxyFrom a stand-in, and named as oneWhere only an indirect signal exists, the score carries the proxy it came from and a lower confidence, never a number dressed as a measurement.
- UnmeasuredHonestly blankA dimension nothing in your data can answer stays unmeasured. It is never a zero, and the plan does not pretend to know it.
Every dimension ends in one word
- Develop the course asks more than you can show
- Maintain close enough to hold at the minimum dose
- Covered nothing to build here
- Unmeasured the course needs it, your data cannot say yet
At the root of every Nymiva season are two readings of the same twelve dimensions. One is the course, taken from the organiser's file. The other is the athlete, taken from their thresholds and their connected training history, each score marked with where it came from and how much weight it can bear. Only a dimension where the course asks for more than the athlete can show becomes a gap. Then the gaps are weighted by the share of the day they fill, which in Vichy means the bike, at more than half the day, sets the order.
With no reader behind it, this page assumes the simplest case, that the gaps sit where Vichy's demands are biggest. It lays out 24 weeks in 5 developmental blocks and a two-week taper. Aerobic endurance leads the opening block in all three sports. The second block puts aerobic durability in front on the bike and in the water, threshold durability on the run. Threshold capacity takes the third block and muscular endurance the fourth, before aerobic endurance returns to lead the last one. Built from a member's own numbers, the order follows their gaps instead of the course's.
Train the bike to protect the run
Which demands matter most across the whole race. A leg's demand counts for as much of the day as that leg takes, so a score of 85 on the bike outweighs the same score on the swim.
- 01Aerobic enduranceBike leg, 54% of the day85 × 54%46
- 02Muscular enduranceBike leg, 54% of the day82 × 54%44
- 03Threshold capacityBike leg, 54% of the day70 × 54%38
The bike takes 54% of the Trained reference band’s day, so its demands carry the most race weight. What the bike leaves in the legs is what the run gets.
Which demand gets a block, and when
The engine freezes one lead focus per sport on every developmental block, holds the rest at maintenance, and verifies before it reprioritises.
An illustration, not your plan. This page has none of your data, so the season below is the engine’s answer to one stated assumption: that your gaps line up with what IRONMAN 70.3 Vichy demands. Your own season is built from your history, your thresholds, the days you can train and the races you have entered, and it will differ from this in its priorities, its sessions and its load.
- 01Run muscular endurance, a practice block4 weeks
- 02Run aerobic endurance, a development block4 weeks
- 03Bike muscular endurance, a practice block4 weeks
- 04Bike aerobic endurance, a development block4 weeks
In the order the allocator places them, general first, most race-like last.
- Week 1PrepPrep
A lead-in week. It develops nothing by design.
- Weeks 2 to 5Foundation 1Closes with a recovery week
- PriorityBike aerobic endurance
- PriorityRun aerobic endurance
- PrioritySwim aerobic endurance
- SupportBike muscular endurance
- SupportRun muscular endurance
- SupportSwim muscular endurance
- SupportBike threshold capacity
- SupportRun threshold capacity
- SupportSwim threshold capacity
- SupportBike aerobic durability
- SupportRun threshold durability
- SupportSwim aerobic durability
- Weeks 6 to 9Foundation 2Closes with a recovery week
- PriorityBike aerobic durability
- PriorityRun threshold durability
- PrioritySwim aerobic durability
- SupportBike aerobic endurance
- SupportRun aerobic endurance
- SupportSwim aerobic endurance
- SupportBike muscular endurance
- SupportRun muscular endurance
- SupportSwim muscular endurance
- SupportBike threshold capacity
- SupportRun threshold capacity
- SupportSwim threshold capacity
- Weeks 10 to 13Foundation 3Closes with a recovery week
- PriorityBike threshold capacity
- PriorityRun threshold capacity
- PrioritySwim threshold capacity
- SupportBike aerobic endurance
- SupportRun aerobic endurance
- SupportSwim aerobic endurance
- SupportBike muscular endurance
- SupportRun muscular endurance
- SupportSwim muscular endurance
- SupportBike aerobic durability
- SupportRun threshold durability
- SupportSwim aerobic durability
- Weeks 14 to 17Event shaping 1Closes with a recovery week
- PriorityBike muscular endurance
- PriorityRun muscular endurance
- PrioritySwim muscular endurance
- SupportBike aerobic endurance
- SupportRun aerobic endurance
- SupportSwim aerobic endurance
- SupportBike threshold capacity
- SupportRun threshold capacity
- SupportSwim threshold capacity
- SupportBike aerobic durability
- SupportRun threshold durability
- SupportSwim aerobic durability
- Weeks 18 to 21Event shaping 2Closes with a recovery week
- PriorityBike aerobic endurance
- PriorityRun aerobic endurance
- PrioritySwim aerobic endurance
- SupportBike muscular endurance
- SupportRun muscular endurance
- SupportSwim muscular endurance
- SupportBike threshold capacity
- SupportRun threshold capacity
- SupportSwim threshold capacity
- SupportBike aerobic durability
- SupportRun threshold durability
- SupportSwim aerobic durability
- Weeks 22 to 23PeakPeak
The taper. Load comes down toward the race, content stays specific.
- Week 24RaceRace
Race week.
Held at maintenance between blocks
- Runmuscular endurance, aerobic endurance, aerobic durability, threshold capacity, threshold durability
- Bikemuscular endurance, aerobic endurance, aerobic durability, threshold capacity, threshold durability
- Swimaerobic endurance, aerobic durability, threshold capacity, threshold durability, muscular endurance
Touches scheduled by each capability’s own decay, at a fraction of its development dose, so earlier work is still there on race day.
The sessions the blocks are built from
One entry per kind of work the block trains, at the intensity that work is meant to be done at. Where the same work runs at several lengths, the entry shows the span it grows across rather than one entry per length.
- Foundation 1 · Weeks 2 to 575 to 240 min
150 to 210 min at Zone 2
BikePower, Zone 2Trains aerobic capacity - Foundation 1 · Weeks 2 to 540 to 270 min
180 to 210 min at Zone 3, then 30 min at Zone 4
BikePower, Zone 3Trains aerobic capacity - Foundation 1 · Weeks 2 to 535 to 120 min
90 min at Zone 2
RunPace, Zone 2Trains aerobic capacity - Foundation 1 · Weeks 2 to 550 min
4 x 1.5 min at Zone 3, 6 min easy between
RunHeart rate, Zone 3Trains aerobic capacity - Foundation 1 · Weeks 2 to 545 to 51 min
4 x 8 min at Zone 2, 1 min easy between
SwimPace, Zone 2Trains aerobic capacity - Foundation 1 · Weeks 2 to 547 to 81 min
3 x 1000 m at Zone 3, 0.3 min easy between
SwimPace, Zone 3Trains aerobic capacity
12× rolling-course surges
0.8 min at Zone 5, then 0.8 min at Zone 5, then 0.8 min at Zone 5, then 0.8 min at Zone 5, then 0.8 min at Zone 5, then 0.8 min at Zone 5, then 0.8 min at Zone 5, then 0.8 min at Zone 5, then 0.8 min at Zone 5, then 0.8 min at Zone 5, then 0.8 min at Zone 5, then 0.8 min at Zone 5, 0.8 min easy between
Compiled by the deterministic course compiler from the organiser’s file: the course’s one repeatable requirement, rehearsed at a dose the progression allows.
- Bike
- 42 min
- Trains threshold durability
- Supports muscular endurance
- Supports high intensity capacity
24 weeks, laid out backwards from race day
The shortest runway Nymiva builds for this event type, with its blocks, recovery weeks, taper and race week in place.
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 11
- 12
- 13
- 14
- 15
- 16
- 17
- 18
- 19
- 20
- 21
- 22
- 23
- 24
- Prep
- Foundation
- Event shaping
- Peak
- Race
- Recovery week
Your own season carries these same phases on your own dates, with the load solved from your fitness and the days you can train, and it changes when your data does.
What each level does on the day
Reference finish times per peer band, the pacing plan the model holds each band to, and where the day is decided.
| Band | Swim | Bike | Run | Finish |
|---|---|---|---|---|
| Recreational2:11 /100m critical swim speed · 2.47 W/kg at 75 kg · 6:08 /km threshold pace | 0:45:05 | 3:39:12 | 2:23:20 | 6:57:37 |
| Trained1:51 /100m critical swim speed · 3.03 W/kg at 75 kg · 5:06 /km threshold pace | 0:38:12 | 3:16:30 | 1:59:11 | 6:03:53 |
| Competitive1:36 /100m critical swim speed · 4.15 W/kg at 75 kg · 4:20 /km threshold pace | 0:33:03 | 2:49:04 | 1:41:16 | 5:13:23 |
| Elite1:26 /100m critical swim speed · 5.27 W/kg at 75 kg · 3:50 /km threshold pace | 0:29:36 | 2:34:25 | 1:29:35 | 4:43:36 |
Pacing plan
- 0 km0.2%29.8 km/h47:26
- 23.6 km-3.1%45.8 km/h0:21
- 23.8 km0.4%28.8 km/h14:45
- 30.9 km3.5%16.5 km/h1:03
- 31.2 km0%30.8 km/h0:37
- 31.5 km7.4%9.4 km/h2:26
- 31.9 km1.1%25.5 km/h0:40
- 32.2 km-3.7%48.5 km/h0:18
77 more segments in the full plan.
- Run: reach 4:20 /km and this course gives back 50:30.
Where it is decided
On the 22 km from kilometre 31 to the top.
A Trained rider spends more than a third of the bike leg on that stretch, and it is where the bands separate. Of the 27 minutes between the Trained and Competitive bikes, more than half are made on the climb. Only a few are made across the whole 37 km back down to town. Gravity is generous on the way home and it is generous to everyone equally.
So the climb decides the day, and it decides it through steadiness rather than strength. The steepest pitch is 215 m at 9.8 percent and costs 1 percent of the bike leg. The ramps near the top come one after another, each short enough to attack. A rider who holds 182 W through all of them reaches the summit with something left for the descent and the run. A rider who answers each ramp out of the saddle reaches it having spent the run already, and then descends on legs that cannot use the false flat.
The run cannot fix what the climb set. The longest stretch of it, 10.1 km without a change of gradient, holds 48 percent of the run leg. A Trained athlete runs 1:59:11 from an input of 5:06 /km threshold pace, twice past the crowd in the arena, and the second loop tells you honestly how the climb went.
Getting it wrong
Saving yourself for the return is the most expensive mistake on this course. The organiser describes the road back to Vichy as smooth and dynamic, perfect for picking up the pace, and it is. It is also where extra power buys the least time, because the road is falling. A rider who holds back on the climb to spend it on the false flat along the Sichon River has spent it in the wrong place.
The second is the 9.8 percent itself. It is the one pitch riders talk about, and it is 215 m long. The ramps higher up matter more. There are four of them, they come late in a long climb, and each one is an invitation to stand up.
The third is dressing for the start. In 2024 the day ran from 8 C to 28 C. What feels right on the bank of the Allier at sunrise is not what you want on the second loop of the Lac d'Allier.
Conditions on the day
- 2026high 25 C, low 12 C
- 2025high 23 C, low 15 C
- 2024high 28 C, low 8 Cwater 25 C
From the organiser’s own records. Not a forecast.
Every session is a claim, every block is a test
A plan is not a calendar. Each key session states what it trains and how that is checked, and each block ends with a public verdict before the next one is chosen.
What a block promises
Bike aerobic endurance moves from your baseline to a stated target by the end of Foundation 1
- The baseline is your measured score when the block starts. The target is the score the model predicts for it.
- Verified at the block’s recovery week, by a field test or a refresh of the supply read from your history.
- Confidence rises by agreement between independent signals, never by one metric crossing a line.
- A block that misses its target is a public miss. The next block is chosen from what was proven, not from what was planned.
- 01Stimulus achievedThe work landed in the zone the session named, for the dose it named.
- 02Partially achievedSome of the work landed. The session banks what it can prove.
- 03Not achievedThe load may have been there. The stimulus was not, so nothing is banked.
- 04Data insufficientNo usable stream. The session is neither credited nor blamed.
- Session verified
- Progression banked
- Block verified
- Priority reassessed
- Plan adapted
Your numbers, this course
Analyze IRONMAN 70.3 Vichy against my fitness
The same simulation and the same Focus Lab read, on your thresholds instead of a band’s. Three numbers give a finish estimate and a partial read. A connected history gives the whole table.
The first 14 days are free.
- Trained band finish
- 6:03:53
- Of the day on the bike
- 54%
- Dimensions scored per leg
- 12
- Season runway shown
- 24 wk
Questions people ask
- How hilly is the IRONMAN 70.3 Vichy bike course?
- The organiser labels it hilly, and the file climbs 892 m over its 90 km loop. Most of it sits between kilometre 31 and kilometre 53, on the way up to La Guillermie, the highest point of the course. The steepest sustained pitch is 215 m at 9.8 percent.
- Where is the IRONMAN 70.3 Vichy swim?
- One loop of 1.9 km in the Allier, starting as the sun comes up. The only water temperature the organiser publishes is 25 C, from 2024. The wetsuit decision is not on the organiser's course page, so check it in race week.
- Is the IRONMAN 70.3 Vichy run flat?
- Yes. It is two loops around the Lac d'Allier and the city's parks, finishing in the arena, and the file measures 106 m of climbing over 21 km. Each loop carries one short drop and nothing else of note.
- How long is the season on this page?
- The illustrative season runs 24 weeks, with five developmental blocks and a two-week taper. It is built from the course alone. A member's season starts from their own numbers and can be longer.
Course data from the organiser’s published files, analysed 23 Sept 2026 by engine 1, demand model 4. Reference times are simulated for a peer band at a stated reference athlete and are not a prediction for anyone. Nothing on this page is medical advice.
IRONMAN® and IRONMAN 70.3® are registered trademarks of World Triathlon Corporation. Nymiva is an independent training platform and is not affiliated with, sponsored by or endorsed by World Triathlon Corporation. Course data is read from the organiser’s public course pages for the purpose of describing the event.