IRONMAN 70.3 Subic Bay Philippines
Course breakdown, historical weather, field analysis, and pacing notes.
Tropical racing in the Philippine heat — warm water and jungle roads
· June 7, 2026
IRONMAN 70.3 Subic Bay takes athletes to a former US naval base on the Philippine coast. A warm-water swim in Subic Bay, a bike through the tropical jungle roads surrounding the base, and a run in full tropical heat. This is one of the hottest 70.3s on the calendar — heat acclimatisation is essential.
- Swim
- 1.9 km
- Ocean
- Bike
- 90.1 km
- ↑952m · Rolling
- Run
- 21.2 km
- ↑81m · Flat
- Air Temp
- 24–33°C
- Water Temp
- 29°C
- Wind
- 13 km/h
- S
Swim Course
Tropical bay swim in warm Philippine waters
The swim takes place in Subic Bay — warm, tropical waters with temperatures around 28–30°C. This is a non-wetsuit swim. The bay is generally sheltered, though tropical water conditions can vary. Warm water removes the wetsuit buoyancy advantage, making swim fitness more important.
- Non-wetsuit swim at 28–30°C
- Sheltered bay conditions
- Tropical water — warm and comfortable
- Swim fitness matters without wetsuit buoyancy
Bike Course
Jungle roads through the former naval base
The bike course winds through the roads of the former Subic Bay naval base and surrounding jungle terrain. The route features rolling hills through tropical vegetation with heat and humidity as constant companions. The jungle roads provide some shade but also trap humid air. This is not a course for chasing fast bike splits — managing body temperature while maintaining output is the real challenge.
- Rolling tropical roads through jungle terrain
- Heat and humidity are the primary challenge
- Former US naval base setting
- Some shade from jungle canopy — but trapped humidity
Run Course
Running in tropical heat — survival pacing
The run takes place in full tropical heat. By mid-morning in the Philippines, temperatures and humidity create extreme conditions for marathon-distance effort. Ice, cold sponges, and aggressive cooling at every aid station are mandatory, not optional. Athletes who have not acclimatised to tropical heat will struggle regardless of run fitness.
- Extreme tropical heat and humidity
- Aggressive cooling strategy essential
- Every aid station matters for ice and hydration
- Heat acclimatisation is the most important preparation
Race Day Conditions
Full tropical heat — the hottest 70.3 on the calendar
June in the Philippines means full tropical conditions. Air temperatures of 30–35°C combined with very high humidity (80%+) create extreme racing conditions. This is arguably the hottest 70.3 on the IRONMAN calendar. Two weeks of heat acclimatisation before the race is strongly recommended. Athletes must plan for dramatically increased fluid and sodium intake.
Race Field Insights
How the Field Performs
Aggregated from 969 finishers (2023–2025)
- Total Starters
- 1,126
- Finishers
- 969
- DNF Rate
- 13.7%
- Years of Data
- 2023–2025
- Median Finish
- 6h 42m
Finish Time Distribution
How the Median Finisher Spends Race Day
What Each Pace Looks Like
Fast | Solid | Median | Back of Pack | Slow (P90) | |
|---|---|---|---|---|---|
| Swim | 35m 17s | 40m 07s | 45m 57s | 51m 53s | 59m 36s |
| Bike | 2h 45m | 2h 58m | 3h 13m | 3h 31m | 3h 47m |
| Run | 1h 53m | 2h 08m | 2h 29m | 2h 49m | 3h 09m |
| Finish | 5h 26m | 6h 02m | 6h 42m | 7h 23m | 7h 58m |
Related reading
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Read postPlan IRONMAN 70.3 Subic Bay Philippines with Keiro
Get a complete pacing strategy for every discipline — built from this course, forecast weather, and your fitness.
Independent analysis. KeiroLabs is not the event organizer and is not affiliated with the race organizer.