Run · Saturday, 3 October 2026 · Week 6, Durability Base
Pace quickens on an easy run as effort edges toward the cap
25 weeks to MDS
The plan called for an easy run, five miles, and I got it done in an hour and four minutes under humid skies. The average heart rate sat three under the cap, but fifteen per cent of the run crept above it as the pace picked up late.
First mile was 12:44 at a heart rate of 125, the last full mile 11:59 at 131, right on the cap. Pace and heart rate moved together rather than one running ahead of the other, which is a reasonable way for an easy run to finish.
Good rhythm throughout, felt strong. Nothing to change this week, I'll just note how the next few easy runs settle.
From my training journal
Easy effort · Good rhythm · Felt strong
- Distance
- 5 mi
- 8.1 km
- Moving time
- 1h 04m
- started 09:43
- Average pace
- 12:39
- per mile
- Heart rate
- 128
- average · max 144
- Climb
- 318 ft
- 97 m
- Conditions
- 13°C
- 80% humidity · wind 8 km/h
Planned easy run, full distance.
Heart rate against my cap
My easy running has a heart rate ceiling of 131 bpm. It keeps the effort aerobic while my legs, tendons and joints catch up with the mileage. A run counts as over the cap when the average is more than 2 beats over it, or more than a fifth of the time sits above it.
Under the cap. Average 128 bpm, with 15% of the run above 131.
Mile by mile
| Mile | Pace | Avg HR | Climb |
|---|---|---|---|
| 1 | 12:44 | 125 | 128 ft |
| 2 | 12:19 | 128 | 13 ft |
| 3 | 13:46 | 129 | 121 ft |
| 4 | 12:36 | 128 | 52 ft |
| 5 | 11:59 | 131 | 13 ft |
Heart rate in orange is above the 131 bpm cap.
Figures from my watch via Intervals.icu, read by the Ultra Event Training app. Heart rate from a watch is a proxy for effort, not a lab measure. The efficiency figures compare speed per heartbeat early and late in a run with a hill correction; they show what changed, not the cause.