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Grade adjusted pace
Flat-equivalent pace
3:39 /km
How to use it
Choose the direction: "actual pace on a slope → flat-equivalent" (understand how hard the climb really was) or "flat pace → pace on a slope" (plan effort for Caucasus trail climbs). Grade in percent: uphill is positive, downhill negative.
Formula and source
Running cost C(i) = 155.4i⁵ − 30.4i⁴ − 43.3i³ + 46.3i² + 19.5i + 3.6 (J/kg/m)
GAP = actual_pace × C(0) / C(grade)
Minetti, Moia, Roi, Susta, Ferretti, 2002 (J Appl Physiol) — the same method Strava uses for GAP
Worked example
Running 5:30/km on an 8% uphill → flat-equivalent ≈ 4:35/km. The effort matches a flat 4:35 pace even though the watch shows 5:30 — normal for Caucasus mountain terrain, not a fitness drop.
Limitations
- The Minetti model is validated for roughly −45% to +45% grades, for running/fast hiking, not scrambling or climbing.
- It doesn't account for surface (rock, mud, snow), altitude, or fatigue — this is a pure geometric grade correction.
- On very steep descents actual cost can diverge due to braking and technique — treat this as guidance, not a guarantee.