Hill repeats
VO₂max-effort intervals run uphill, with the gradient supplying the resistance and capping the impact.
Also called: uphill intervals, hill reps.
Hills give you the aerobic cost of interval running with less eccentric loading than the same effort on the flat, because you land on ground that comes up to meet you. That makes them a good way to introduce intensity in base phase and a good option for runners with a history of impact-related niggles. Run the effort, not the pace — a watch will tell you lies on a gradient, which is the whole reason grade-adjusted pace exists.
The session
Shown at a 4:00 marathon reference — 49 min total, about 7.2 km, including 9 min of quality work.
Warm-up
- 12 min easy (6:43–7:24/km)
- 4 × 20 s strides, jog back between
Main set
- 6 × 75 s uphill, 5K effort, 3 min jog between
Cool-down
- 10 min easy (6:43–7:24/km)
Why this session works
Long hill repeats reach VO₂max at slower speeds — the gradient supplies the intensity while ground-reaction forces stay low. A robust way to build aerobic power while sparing the legs.
Use a steady 4–6% climb; jog back down for recovery.
Source: Barnes & Kilding 2015. Training phase: build.
Run it at your own paces
Open the workout generator and enter a recent race time — every rep length, recovery and target pace is recalculated for your fitness, and the session exports to .fit for a Garmin watch.
Frequently asked questions
What is a hill repeats?
VO₂max-effort intervals run uphill, with the gradient supplying the resistance and capping the impact. Hills give you the aerobic cost of interval running with less eccentric loading than the same effort on the flat, because you land on ground that comes up to meet you.
How long is this session?
At a 4:00 marathon reference it comes to 49 min and about 7.2 km, of which 9 min is prescribed quality work. The generator scales both to your own paces, so a faster runner covers more ground in the same time.
Who is this workout for?
It is written for the build phase of a marathon build. The distances shown suit a 4:00 marathoner; enter your own recent race time in the generator and every rep length and target pace is recalculated for you.
More vo₂max intervals sessions
- VO₂max intervals — Repeats of two to five minutes at around the pace you could hold flat out for ten minutes, with equal or slightly shorter recoveries.
- Cutdown intervals — Intervals that get shorter and faster as the session goes on.
- Pyramid intervals — Reps that climb in length to a peak and then come back down.
- 30/30 intervals — Thirty seconds hard, thirty seconds easy, repeated — accumulating time near VO₂max without the strain of long reps.