Trail Running Pace: What Is a Good Pace, and How to Work Out Yours

What is a good trail running pace per km? Benchmark paces by road pace and terrain, what slows you on trails, and a free calculator for your own route.

A good trail running pace is the one that matches the ground under you, not a number carried over from the road. On a smooth, gently rolling trail most runners hold within 5 to 10% of their flat pace. On a hilly course with 40 to 50m of climbing per kilometre, expect 20 to 25% slower. On a steep, technical mountain course, 50% slower is normal and 80% is not unusual, even for strong runners.

Need a pace for your own route? Use the trail pace calculator: enter your flat pace, the distance, the elevation gain and the terrain.

This guide gives you benchmark trail paces by road pace and course type, explains what slows you down, and shows how to judge whether your own pace is good. If you want the number for a specific route, the trail running pace calculator works it out from your flat pace, the distance, the elevation and the terrain, and shows your grade adjusted pace for every gradient.

What is a good trail running pace per km?

The table below uses the same model as our calculator: Strava's grade adjusted pace speed factors, fitted to heart rate data from real runs (Robb, 2017), plus a terrain multiplier. Find your comfortable flat pace in the left column, then read across to the kind of course you run. The figures are moving pace: they leave out aid station stops and the slowdown that fatigue adds in races longer than about three hours.

So if you run 6:00/km on a flat road and averaged 7:15/km on a half marathon with 900m of climbing, that is a good trail pace: it is the same effort. Averaging 7:15/km on a flat towpath would not be.

Per mile, multiply by 1.609: a 6:00/km pace is 9:39 per mile, and 8:54/km is 14:19 per mile.

Why trail pace and road pace differ

Gradient does most of the work

Climbing costs far more energy than running on the flat, and gentle descents cost a little less. Research on the energy cost of running across gradients shows the cost rising steeply with every percent of climb (Minetti et al., 2002), which is why grade adjusted pace exists. Here is what a 5:30/km flat effort looks like on different gradients in our model:

Two things stand out. Descents only speed you up to about -10%; beyond that you brake, and at -20% you are slower than on the flat (Vernillo et al., 2017). And above roughly 15 to 20%, hiking is about as fast as running for most people while costing less energy, which is why good trail runners walk steep climbs without guilt.

Surface

Roots, rock, scree and mud slow you down in ways an elevation profile cannot show. Our calculator applies a multiplier for this: none on fire roads and smooth paths, about 8% on ordinary singletrack, about 18% on rocky or stepped trail, and about 30% on alpine ground where you use your hands.

Altitude

Thinner air lowers the ceiling on aerobic effort. In trained endurance athletes, maximal oxygen uptake fell by roughly 6 to 7% for every 1,000m of altitude (Wehrlin and Hallén, 2006). Below about 1,500m you will not notice much; on a race that climbs to 2,500m, expect your climbing pace to drop even at the same heart rate.

Distance and fatigue

Grade adjusted pace describes effort, not endurance. It does not know you are six hours in. On long races, pace falls further in the second half, mostly on descents, where damaged quads cannot absorb the impact. That is what the race time predictor is for: it starts from a real race result, so fatigue is already built in.

How to tell if your trail pace is good

Comparing raw pace across trail runs is misleading. Compare these instead:

• Grade adjusted pace. Strava, Garmin and our calculator all convert a hilly run to its flat equivalent. If your GAP on a trail run is close to your pace on a flat run at the same effort, you ran the trail well.
• Heart rate at a given GAP. If your heart rate on a familiar loop drops over a few weeks at the same grade adjusted pace, your fitness is improving even if the watch shows a slow average.
• Vertical speed on climbs. Metres climbed per hour is the clearest trail fitness marker. As a rough guide: 300 to 500m per hour for new trail runners, 500 to 700m for regular trail runners, 700 to 1,000m for strong amateurs, and above 1,000m for elite mountain runners. Our guide to vertical pace and elevation per hour covers how to train it.
• Your result against the course, not the clock. ITRA scores and similar systems adjust for course difficulty for the same reason. Our ITRA km-effort calculator shows how hard a course is compared with a flat run of the same length.

Estimating a trail race time by hand

If you are away from a screen, this old walking-and-running rule gets you close:

1. Start with your flat pace for the distance and multiply by the kilometres.
2. Add about 1 minute for every 100m of climbing (more on steep ground).
3. Add about 30 seconds for every 100m of descent if the descents are technical.
4. Add 10 to 15% if the surface is rough.

For a 21 km trail half marathon with 900m up and 900m down, run by someone with a 5:30/km flat pace: 1:55:30 base, plus 9 minutes for the climbing, plus 4:30 for technical descents, plus about 11:30 for the surface, gives roughly 2:20.

It is a useful sanity check. For a race you care about, the pace calculator or the race time predictor will be closer, and the pacing planner splits a GPX course into sections with a target time for each.

Train by effort, race by effort

Pace targets fall apart on trails because the same pace can be easy on one kilometre and impossible on the next. Train with heart rate or perceived effort instead:

On race day, the same principle applies:

• Run the first 20% of the race so it feels easy. Most blow-ups start with a fast first climb.
• Walk steep climbs early, before you are forced to.
• Use aid stations and landmarks as targets, not kilometre splits.
• Eat and drink on a schedule. Many second-half pace drops are fueling problems rather than fitness problems.

Key takeaways

• A good trail pace depends on the course: about 2% slower than flat on smooth rolling trail, 20% on a hilly half marathon, and 50% or more on technical mountain ground.
• Gradient is the biggest factor, then surface, altitude and fatigue.
• Judge trail runs by grade adjusted pace, heart rate at a given GAP and vertical speed, not by average pace.
• For your own number, use the trail running pace calculator; for a race finish time from a recent result, use the race time predictor.

Citations

• Minetti, A. E., Moia, C., Roi, G. S., Susta, D., & Ferretti, G. (2002). Energy cost of walking and running at extreme uphill and downhill slopes. Journal of Applied Physiology, 93(3), 1039-1046.
• Wehrlin, J. P., & Hallén, J. (2006). Linear decrease in VO2max and performance with increasing altitude in endurance athletes. European Journal of Applied Physiology, 96(4), 404-412.
• Vernillo, G., et al. (2017). Biomechanics and physiology of uphill and downhill running. Sports Medicine, 47(4), 615-629.
• Robb, D. (2017). An Improved GAP Model. Strava Engineering. https://medium.com/strava-engineering/an-improved-gap-model-8b07ae8886c3

Frequently Asked Questions

What is a good trail running pace per km?

It depends on the ground. Using a grade adjusted pace model, a runner who holds 6:00/km on flat road runs about 6:06/km on smooth rolling trail, 7:17/km on a hilly half marathon with 900m of climbing and about 8:54/km on technical mountain trail. A good trail pace is one that matches your flat pace once gradient and surface are accounted for.

How much slower is trail running than road running?

Anywhere from almost the same to twice as slow. Smooth, gently rolling trail costs only a few percent. A hilly course with 40 to 50m of climbing per kilometre costs about 20 to 25%. Steep, technical mountain terrain costs 50% or more, and alpine ground can cost 80%.

How do I calculate my trail running pace?

Enter your flat pace, the distance, the elevation gain and loss and the type of terrain into Trailia's free trail running pace calculator. It returns your average trail pace, finish time, climbing and descending pace, and a grade adjusted pace table for every gradient from -20% to +30%.

What is grade adjusted pace?

Grade adjusted pace (GAP) converts your pace on a slope into the flat pace that would take the same effort. Running 8:01/km up a 10% grade is roughly the same effort as 5:30/km on the flat. It lets you compare hilly and flat runs fairly.

Should I run or walk uphill in a trail race?

For most runners, hiking is about as fast as running once the gradient passes 15 to 20%, and it costs much less energy. Elite mountain runners walk the steepest climbs too. Walk early, before you are forced to.

What is a good vertical speed for trail running?

As a rough guide: 300 to 500m of climbing per hour for new trail runners, 500 to 700m for regular trail runners, 700 to 1,000m for strong amateurs and more than 1,000m per hour for elite mountain runners.

How can I predict my trail race finish time?

The quick method: flat pace times distance, plus about 1 minute per 100m of climbing, plus 30 seconds per 100m of technical descent, plus 10 to 15% for rough ground. For a closer estimate, Trailia's race time predictor starts from a recent race result and the course profile, so fatigue is built in.

• Read on Trailia: https://trailia.run/guides/training/trail-running-pace-guide-calculator
• More training guides: https://trailia.run/guides/training
• All guides: https://trailia.run/guides
• Free trail running tools: https://trailia.run/tools
• Trailia homepage: https://trailia.run