About KAI70k
KAI70k is the 68.6km ultra trail at Mt. Fuji 100 2026 (Fujiyoshida, Japan). The race starts on April 25, 2026 at 02:00 PM. It starts and finishes in Fujiyoshida. The time limit is 21 h.
Race strategy
Hold a steady pace and save energy for every section.
- Steep 42% wall. Control your pace and stay focused.
- 888m descent. Go easy, save your quads.
- The finish is runnable. Save your legs to run it all the way.
- Long race. Control your HR and effort. Early mistakes cost the most.
- Ease into the early runnable section, save your quads on the descents until 48.7km, 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–12.4km · 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. Running pays off here: run wherever you can.
- Work · 12.4km–30.9km · Descent of 268m averaging 11%, descent of 323m averaging 12%. Plus 2 more climbs. This is where the race is built: steady, solid effort. 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. Running pays off here: run wherever you can.
- Fade · 30.9km–61.4km · Climb of 929m, high point 1627m, descent of 888m averaging 12%, climb of 637m. Plus 1 more descent. Your energy fades, and that's normal: hold a steady effort and stop counting the miles. 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. Hike the steepest pitches. Your heart rate drifts down on its own: don't chase your early-race numbers, go by feel.
- Home · 61.4km–67.3km · 6.0km of runnable trail. No heroics: settle back into your own effort and hold it to the line. Running pays off here: run wherever you can.
Course
The course climbs 2921m+. With 43m/km of climbing, this is a rolling, mostly runnable course. By gradient, 34% of the distance is uphill, 38% downhill and 29% flat. The longest climb runs 10.6km at an average 8.7% grade (929m of vertical). The longest descent runs 7.2km at an average 12.3% grade (888m of vertical). The steepest climb averages 47.5% over 0.2km. The steepest descent drops at 53.8% over 0.2km. Flat-equivalent effort: 93.6 FlatKM.
Poles
Trekking poles are worth taking: about 9.1km of the course favours them.
Quad damage
Quad damage risk is moderate (index 37 of 100), with 40% of the load in the first half: 3 descents deserve a plan and a couple of downhill sessions before race day.
- Ease into the early runnable section, save your quads on the descents until 48.7km, then run your race pace.
- #3 · 21.3–23.6 km · 268 m D−, -11.4% · 43.7 km ahead → control
- #2 · 28.2–30.9 km · 323 m D−, -12.2% · 36.5 km ahead → control
- #1 · 41.5–48.7 km · 888 m D−, -12.3% · 18.6 km ahead → control
- 56.9–61.4 km · 541 m D−, -12.1% · 6.0 km ahead → your pace
Weather
On race day, start temperatures have historically ranged from 10°C to 19°C, with around 3°C at the highest point; the chance of precipitation is about 33%. Heavy rain of 10.0mm or more falls on about 13% of days around this date.
Results
1,108 finishers completed the 2026 edition. Men's winner: Tracen Knopp (United States) in 6:38:08. Women's winner: Klaire Rhodes (United States) in 7:15:09.
This page has the full results and splits, a pacing and nutrition planner, a gradient matrix, an interactive elevation profile and historical weather for KAI70k.
Other distances of Mt. Fuji 100 2026FUJI100mi (165km)·ASUMI40k (38.5km)
Other editions of KAI70k2027
Official websitemtfuji100.com