Why does a lot of elevation gain make your pace look slower?

The short answer

Pace is distance divided by time, nothing else. It does not read elevation, grade, footing, or anything about what the ground under a route looked like. A hike with real climbing in it takes longer to cover a given distance than a flat one does, so the pace number comes out slower — not because anything went wrong with the recording, but because the number is doing exactly what it is built to do: report how much ground was covered against how much time it took, with the climb simply baked into that time.

What pace is actually built from

Every pace figure, whether it is the average shown at the end of a hike or a moment-to-moment number along the way, comes from the same two inputs: distance covered and time it took to cover it. Divide one by the other and pace falls out. Nowhere in that calculation is there a term for how much of the route went uphill, how steep it was, or how much harder each of those steps was than a step on flat ground. Distance is measured in a straight line along the recorded track, in two dimensions along the map, regardless of whether the route stayed level or climbed a ridge to get there.

This is exactly the same reason two hikes of identical distance can post different pace numbers even when nobody was moving faster on one than the other — the ground itself set the pace by making one route slower to cross, and the number is just reporting the result honestly.

Why climbing costs more time for the same distance

Covering a kilometre of level trail and a kilometre of trail that climbs steeply are not the same task, even though a GPS track measures both as exactly a kilometre. Footing changes, the trail is rougher, breaks to look at a view or check the map happen more often, and simply moving a body uphill against gravity takes longer per step than moving it forward on flat ground. None of that shows up as a separate number anywhere — it all shows up as more time spent to cover the same horizontal distance, which is precisely what pace is built to reflect back.

A route with a long, steady climb in the middle will almost always show a slower average pace than the same length of trail on level ground, and a route that alternates climbing and descending will show a pace somewhere between the two, weighted by how much of the distance was spent doing which.

Why the number can feel wrong even though it is not

A steep climb can feel like real, deliberate effort while it is happening, which makes a slower pace afterward feel like a odd thing to see next to that effort — surely working harder should show up as a better number, not a worse one. Pace is not measuring effort, though. It is measuring how much horizontal distance got covered per unit of time, and climbing is, by its nature, slower going per horizontal metre than flat ground, however much harder each of those metres was to earn. The two things — how hard a stretch felt and how fast it was covered — are related but not the same measurement, and only one of them is what pace reports.

Comparing two hikes fairly means looking at both numbers

A flat five-kilometre walk and a five-kilometre ridge hike with real elevation gain are not a fair pace comparison on distance alone, because distance alone leaves out the one variable that made the two routes take different amounts of time. Reading pace next to the elevation gain figure for the same hike — rather than pace on its own — is what actually explains the number: a slow pace paired with a lot of climbing is telling a consistent story, not signalling that anything is off. Two hikes only compare cleanly on pace when the terrain underneath them was actually similar.

Things that trip people up

• Assuming a slower pace on a climbing day means the track lost accuracy or missed distance — the distance is usually fine; time simply took longer to cover it, which is what a climb does.
• Comparing pace across two hikes without checking whether one of them had significantly more elevation gain — that comparison is only fair when the terrain was actually similar.
• Expecting pace to reward a hard climb with a better number — pace reports distance over time, not effort, and a hard climb is almost always slower going per horizontal metre, however demanding it felt.
• Reading a slow pace on a mixed hike as one continuous problem rather than a blend — a route that alternates flat and steep stretches shows an average sitting somewhere between the two, not a single explanation.

Where TrailCam fits in

TrailCam shows pace and elevation gain side by side after a hike, with the climb drawn as a profile underneath the map so a slow stretch of pace lines up visually with the part of the route that was actually climbing. Reading the two together, rather than pace alone, is usually what explains a number that looked odd on its own. TrailCam is free to download.