IRONMAN 70.3 · Danang · 9 May 2027
How to train for IRONMAN 70.3 Da Nang
People open the Da Nang profile and decide they have found the easy one. The organiser marks the bike flat and the run flat, the bike climbs 144 m in 90.6 km, and the run climbs 17 m. All of that is true. It is also the wrong table to read.
Read the weather instead. A high of 35 C in 2025, 34 C the year before, and a sea at 29 C for the swim in 2026. On this course the thing you are racing is not the road.
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.
- Swim1.92 km5 m upCourse file
- Bike90.6 km144 m upCourse file
- Run21.3 km17 m upCourse file
Everything starts and ends at East Sea Park, which the organiser also calls Bien Dong Park, with both transitions on the beachfront so you rack once and use the same setup twice. The swim is 1 lap of a clockwise triangle, 1.9 km from a rolling start at sunrise, two red buoys marking the turns, then straight up the sand into T1.
The bike is a single loop. It leaves along the Vo Nguyen Giap and Hoang Sa coastline, pushes north over the Man Quang and Thuan Phuoc bridges, and then gives you 11 km beside the sea on Nguyen Tat Thanh. From there it follows the eastern bank of the Han River and carries on into Quang Nam for a 16.5 km straight on Lac Long Quan Road. A right turn onto Vo Chi Cong takes you out among the rice paddies to the turnaround, and you ride home along the same corridor.
The file shows how little of that is climbing. Two rises longer than half a kilometre, the steeper of them 638 m at 3.4 percent, and 97.1 percent of the whole course flat by distance. The longest unbroken piece of road is a 30 km flat stretch in the middle of the loop, and the engine gives it 33 percent of the bike leg. The steepest climb gets 1.4 percent.
The run is two laps of one out-and-back. From the transition on Son Thuy Beach you turn right onto Truong Sa Rd and run parallel to the sand to a U-turn at 5.3 km, come back past the crowd, turn again at the transition and repeat the loop. The finish is on the sandy beach at the Hyatt. The engine reads all 21.3 km as a single flat segment.
Course shape by distance
- Flat 97%
- Climbing 2%
- Descending 1%
The longest stretches
- Bike, climbing0.64 km1% of the bike
- Bike, flat30 km33% of the bike
- Run, flat21.3 km100% 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.
Heat, before anything else. Environmental resilience scores 90 on the swim, on the bike and on the run, the highest reading on every leg. Because the bike fills 51 percent of a Trained athlete's day, the bike's version of it tops the whole cross-leg ranking. The lows are no relief either. The coolest low across the three editions the organiser publishes was 25 C.
Behind the heat sits the familiar half-distance pair. Aerobic endurance reads 85 on every leg. Muscular endurance reads 80 on the bike and the run, 81 in the water. What the course does not want is just as plain. High-intensity capacity reads 45 on the bike and strength and force 41, because every rise on the loop is short and shallow. The one surprise is in the sea. Technical skill scores 72 for the swim against 35 on the bike, which is what a triangle of open water with two turn buoys asks for: a straight line between them.
Now the bands. A Trained athlete swims 38:32, rides 2:57:09 at 182 W and runs 2:00:55, finishing in 5:46:36. The Competitive band finishes in 5:02:45, riding 2:36:42 from 4.15 W/kg at 75 kg and running 1:42:44 from 4:20 /km threshold pace. Neither of those days has a hill in it worth the name. Both of them end with a long run on hot beachfront road.
- Environmental resilience90
- Aerobic endurance85
- Muscular endurance81
- Technical skill72
- Threshold capacity70
- Aerobic durability65
- Threshold durability65
- Fueling resilience55
- High-intensity capacity40
- Anaerobic capacity25
- Strength / force20
- 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
What you see above is half a comparison. Nymiva reads the other half from the athlete, scoring the same twelve dimensions from their thresholds and connected training history and noting where each score came from and how far it can be trusted. A dimension becomes a gap only where the course asks for more than the athlete can show, and each gap is weighted by how much of the day its leg fills. At Da Nang the bike is half the day and the swim is 11 percent of it, so a modest bike gap outranks a bigger one in the water.
No athlete stands behind this page, so the season under it cannot know anyone's gaps. It takes the plain assumption that they sit where the demands are largest and lays out 24 weeks with 5 developmental blocks and a two-week taper. Aerobic endurance leads the first block in all three sports. Aerobic durability leads the second on land while the swim works on threshold capacity. Threshold capacity moves to the bike and run in the third, and technical skill leads in the water. Muscular endurance leads the fourth block, and aerobic endurance returns to lead the last one before the taper. A member's season is built from their own numbers and will not look like this one.
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.
- 01Environmental resilienceBike leg, 51% of the day90 × 51%46
- 02Aerobic enduranceBike leg, 51% of the day85 × 51%43
- 03Muscular enduranceBike leg, 51% of the day80 × 51%41
The bike takes 51% 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 Da Nang 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
- SupportSwim technical skill
- SupportBike threshold capacity
- SupportRun threshold capacity
- SupportSwim threshold capacity
- SupportBike aerobic durability
- SupportRun aerobic durability
- Weeks 6 to 9Foundation 2Closes with a recovery week
- PrioritySwim threshold capacity
- PriorityBike aerobic durability
- PriorityRun aerobic durability
- SupportBike aerobic endurance
- SupportRun aerobic endurance
- SupportSwim aerobic endurance
- SupportBike muscular endurance
- SupportRun muscular endurance
- SupportSwim muscular endurance
- SupportSwim technical skill
- SupportBike threshold capacity
- SupportRun threshold capacity
- Weeks 10 to 13Foundation 3Closes with a recovery week
- PrioritySwim technical skill
- PriorityBike threshold capacity
- PriorityRun threshold capacity
- SupportBike aerobic endurance
- SupportRun aerobic endurance
- SupportSwim aerobic endurance
- SupportBike muscular endurance
- SupportRun muscular endurance
- SupportSwim muscular endurance
- SupportSwim threshold capacity
- SupportBike aerobic durability
- SupportRun 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
- SupportSwim technical skill
- SupportBike threshold capacity
- SupportRun threshold capacity
- SupportSwim threshold capacity
- SupportBike aerobic durability
- SupportRun 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
- SupportSwim technical skill
- SupportBike threshold capacity
- SupportRun threshold capacity
- SupportSwim threshold capacity
- SupportBike aerobic durability
- SupportRun 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, technical skill
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
3× course-matched climbs
1.5 min at Zone 5, then 1.5 min at Zone 5, then 1.5 min at Zone 5, 57.8 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
- 145 min
- Trains high intensity capacity
- Supports strength force
- Supports muscular endurance
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 | 0:45:28 | 3:12:17 | 2:25:24 | 6:33:09 |
| Trained1:51 /100m critical swim speed · 3.03 W/kg at 75 kg · 5:06 /km threshold pace | 0:38:32 | 2:57:09 | 2:00:55 | 5:46:36 |
| Competitive1:36 /100m critical swim speed · 4.15 W/kg at 75 kg · 4:20 /km threshold pace | 0:33:19 | 2:36:42 | 1:42:44 | 5:02:45 |
| Elite1:26 /100m critical swim speed · 5.27 W/kg at 75 kg · 3:50 /km threshold pace | 0:29:51 | 2:23:07 | 1:30:53 | 4:33:51 |
Pacing plan
- 0 km0%30.8 km/h14:01
- 7.2 km3.4%16.8 km/h2:17
- 7.84 km0%30.8 km/h1:38
- 8.67 km-3.6%48.1 km/h0:46
- 9.29 km0%30.8 km/h43:52
- 31.8 km3.3%17.1 km/h3:17
- 32.7 km-1.1%36.3 km/h0:46
- 33.2 km-3.9%49.4 km/h0:47
5 more segments in the full plan.
- Run: reach 4:20 /km and this course gives back 43:51.
Where it is decided
On Truong Sa Rd, but it is settled out on the bike.
By the time a Trained athlete racks the bike, they have spent 38:32 in the sea and 2:57:09 on the loop, and the sunrise swim is hours behind them. Then comes 21.3 km of flat road beside the beach, which the Trained band covers in 2:00:55 from an input of 5:06 /km threshold pace. There is no descent to recover on and no climb that excuses a slower kilometre. Only the U-turns change, and the temperature.
What you bring to that run was decided in the middle of the ride. Ask the engine for a session built from this bike file and it hands back something close to empty: three short climbing efforts of a minute and a half, each one followed by close to an hour of easy spinning. That is an honest portrait of the leg. It barely asks for anything above your steady number. It asks you to hold that number for the whole 30 km flat stretch while the sun climbs, with nothing on the road to tell you when you have drifted above it.
The Competitive band runs 1:42:44 and the Trained band 2:00:55. On paper the difference is threshold pace. On the day it is also who rode the middle of the loop at 182 W as planned, and who rode it at whatever the flat road and a helpful breeze offered.
Getting it wrong
Swimming the warm water as if it were a warm-up. The sea was 29 C in 2026, the rolling start lets you choose your own pace from the first stroke, and the triangle feels easy. Push it anyway and you reach Bien Dong Park already hot, with the longest leg of the day still in front of you.
Letting the straights set the power. Nguyen Tat Thanh gives you 11 km of seaside road and Lac Long Quan Road gives you 16.5 km without a bend, with residents cheering from the roadside. This is where a planned number creeps up a few watts at a time. No gradient arrives to interrupt it, so decide the number before you start and ride it.
Running the first loop for the crowd. The out-and-back returns you to Son Thuy Beach after each 5.3 km leg of it, into the families lining the street, and the first pass is the loudest. Aid stations come every 1.1 to 1.3 km. Use them from the start as part of the pacing, not as something to skip while you feel good, because the second loop is identical to the first except for the heat.
Conditions on the day
- 2026high 33 C, low 25 Cwater 29 C
- 2025high 35 C, low 27 Cwater 28 C
- 2024high 34 C, low 25 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 Da Nang 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
- 5:46:36
- Of the day on the bike
- 51%
- Dimensions scored per leg
- 12
- Season runway shown
- 24 wk
Questions people ask
- How hilly is the IRONMAN 70.3 Da Nang bike course?
- Hardly at all. The single 90 km loop climbs 144 m in total and 97.1 percent of the whole course is flat by distance. The two longest rises are 638 m at 3.4 percent and 933 m at 3.3 percent, on a route north that crosses the Man Quang and Thuan Phuoc bridges.
- How hot is IRONMAN 70.3 Da Nang?
- The organiser logged highs of 33 C in 2026, 35 C in 2025 and 34 C in 2024, and the low never fell below 25 C. The sea at East Sea Park measured 29 C in 2026 and 28 C in 2025. The wetsuit decision is not on the organiser's course page, so check it in race week.
- What is the IRONMAN 70.3 Da Nang run course like?
- Two identical loops of an out-and-back on Truong Sa Rd, parallel to the beach. The far U-turn sits at 5.3 km and the near one at the transition on Son Thuy Beach. The organiser places aid stations every 1.1 to 1.3 km, and the finish is on the sandy beach at the Hyatt.
- 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 own season starts from their numbers and can be longer.
Course data from the organiser’s published files, analysed 24 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, and 5150 is a trademark, 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.