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  7. HOKA Chiang Mai Thailand by UTMB
HOKA Chiang Mai Thailand by UTMB
168km16896km9656km5656km5639km3921km2121km2120km2017km17

Inthanon 20

UTMB World Series
20.0km
December 4
Chiang Mai,
Thailand
utmb·source

Race Pace Calculator · GPX Analyzer · Trail Finder

Other races: Thailand

Read

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  • Hill Training for Trail Runners: Train the Descents
  • Downhill Running Muscle Damage: Why Descents Wreck Quads

Inthanon 20 · Race profile

Distance
20.0km
FlatKM
28.8
Max
1460m
Min
995m

About Inthanon 20

Inthanon 20 is the 20.0km trail race at HOKA Chiang Mai Thailand by UTMB 2025 (Chiang Mai, Thailand). The race starts on December 4, 2025.

Race strategy

Run easy on the first mountain, then go all out on the second.

  • 671m descent. Go easy, save your quads.
  • Start easy and control your HR up to 13.6km.
  • Control your HR on the first mountain, save your quads on the way down from it until 13.6km, then run your race pace.
  • Start · 0.0km–1.5km · Race-day nerves push your heart rate up: don't follow the crowd, find your own rhythm.
  • Settle in · 1.5km–13.6km · Descent of 671m averaging 6%, high point 1460m. Plus 1 more climb. Ease in: hold back more than feels necessary. The race is still ahead. Climb by heart rate or breathing, not pace. This descent is hard on the legs: short steps, stay in control, poles if you have them.
  • Home · 13.6km–20.1km · Climb of 350m. Build to the finish: leave whatever you have left out on the course. Climb by heart rate or breathing, not pace.

Course

By gradient, 37% of the distance is uphill, 43% downhill and 20% flat. The longest climb runs 6.5km at an average 5.4% grade (350m of vertical). The longest descent runs 10.6km at an average 6.3% grade (671m of vertical). The steepest climb averages 26.6% over 0.3km. The steepest descent drops at 28.4% over 0.4km. Surface: 47% road, 41% trail, and 12% smooth. Flat-equivalent effort: 28.8 FlatKM.

Poles

The course is runnable enough that trekking poles are not needed.

Quad damage

Quad damage risk is low (index 12 of 100): a few descents worth noting, none of them decisive.

  • Control your HR on the first mountain, save your quads on the way down from it until 13.6km, then run your race pace.
  • #1 · 3.0–13.5 km · 671 m D−, -6.4% · 6.5 km ahead → control

Weather

On race day, start temperatures have historically ranged from 15°C to 21°C, with around 17°C at the highest point; the chance of precipitation is about 7%.

Results

721 finishers completed the 2025 edition. Men's winner: Hiroki Kai (Japan) in 1:43:52. Women's winner: Yuri Yoshizumi (Japan) in 1:53:41.

This page has the full results and splits, a pacing and nutrition planner, a gradient matrix, an interactive elevation profile and historical weather for Inthanon 20.

Other distances of HOKA Chiang Mai Thailand by UTMB 2025Chiang Dao 160 (168km)·Elephant 100 (96.0km)·Hmong 50 (56.0km)·Hmong 50 Night (56.0km)·Inthanon 50 (39.0km)·Suthep 20 Night (21.0km)·Suthep 20 Day (21.0km)·Chedi 20 (17.0km)

Other editions of Inthanon 202026

Official websitechiangmai.utmb.world