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Quad Rock
81km8140km40

Quad Rock 25mi

40.0km·1700m+
May 10
Fort Collins,
United States
itra

Race Pace Calculator · GPX Analyzer · Trail Finder

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Quad Rock 25mi · Race profile

Distance
40.0km
Gain
1700m+
FlatKM
54.1
Max
2157m
Min
1663m

About Quad Rock 25mi

Quad Rock 25mi is the 40.0km trail race at Quad Rock 2025 (Fort Collins, United States). The race starts on May 10, 2025.

Race strategy

Hold a steady pace and save energy for every section.

  • 370m descent. Go easy, save your quads.
  • Start easy and control your HR up to 20.8km.
  • Hold your race pace up to Arthurs Rock, but stay in control.
  • Ease into the early runnable section, save your quads on the descents until 15.3km, then run your race pace, and start the final descent from 32.5km under control, then go all out near the bottom.
  • Start · 0.0km–2.1km · Race-day nerves push your heart rate up: don't follow the crowd, find your own rhythm.
  • Settle in · 2.1km–20.8km · Descent of 370m averaging 10%. Plus 2 more climbs. 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. Running pays off here: run wherever you can.
  • Work · 20.8km–32.5km · Descent of 508m averaging 7%, high point 2159m. Plus 1 more climb. This is where the race is built: steady, solid effort. Climb by heart rate or breathing, not pace.
  • Home · 32.5km–39.6km · Descent of 426m averaging 6%. No heroics: settle back into your own effort and hold it to the line. Very long descent: first half under control, then even, let go only near the end.

Course

The course climbs 1700m+. With 43m/km of climbing, this is a rolling, mostly runnable course. By gradient, 42% of the distance is uphill, 42% downhill and 16% flat. The longest climb runs 5.6km at an average 8.6% grade (480m of vertical). The longest descent runs 7.1km at an average 6.0% grade (426m of vertical). The steepest climb averages 16.6% over 0.5km. The steepest descent drops at 19.3% over 0.2km. Surface: 99% trail. Flat-equivalent effort: 54.1 FlatKM.

Summits

The course also passes close to Arthurs Rock (2067m).

Poles

Poles bring little benefit here: only about 1.7km of pole-friendly terrain.

Quad damage

Quad damage risk is moderate (index 23 of 100), with 33% of the load in the first half: 1 descent deserves a plan and a couple of downhill sessions before race day.

  • Ease into the early runnable section, save your quads on the descents until 15.3km, then run your race pace, and start the final descent from 32.5km under control, then go all out near the bottom.
  • #1 · 11.4–15.3 km · 370 m D−, -9.7% · 24.4 km ahead → control
  • 20.8–27.8 km · 508 m D−, -7.3% · 11.9 km ahead → your pace
  • 32.5–39.7 km · 426 m D−, -6.0% · 0.0 km ahead → even, first half under control, let go at the end

This page has a pacing and nutrition planner, a gradient matrix, an interactive elevation profile and historical weather for Quad Rock 25mi.

Other distances of Quad Rock 2025Quad Rock 50mi (81.0km)