Long run · Sunday, 18 October 2026 · Week 8, Durability Base
Long run, 26.3 miles
23 weeks to MDS
My write-up for this run isn't up yet. Everything the watch recorded is below.
- Distance
- 26.3 mi
- 42.3 km
- Moving time
- 6h 27m
- started 07:06
- Average pace
- 14:43
- per mile
- Heart rate
- 125
- average · max 150
- Climb
- 1759 ft
- 536 m
- Conditions
- 9°C
- 71% humidity · wind 18 km/h
Planned long run, distance changed on the day.
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 125 bpm, with 14% of the run above 131.
How well the running held up
I compare how efficiently I was running early in the run (speed for each heartbeat, corrected for hills) with the late part. The drop was 14.7%. Over 5% is what I call a late fade. That band is a coaching convention, not a validated threshold.
A sustained drop began around 2h 43m into the run.
Late on, pace slowed 7.6% and heart rate rose 8.3%.
First half against second half
Comparing pace against heart rate in the first half with the second, the gap was 11.8%. Under 5% is the convention I coach to: it suggests the aerobic side coped with the length of the run. It says nothing about why.
Mile by mile
| Mile | Pace | Avg HR | Climb |
|---|---|---|---|
| 1 | 13:28 | 118 | 33 ft |
| 2 | 13:53 | 121 | 0 ft |
| 3 | 13:56 | 116 | 7 ft |
| 4 | 15:35 | 118 | 161 ft |
| 5 | 13:01 | 116 | 7 ft |
| 6 | 14:52 | 118 | 135 ft |
| 7 | 13:42 | 120 | 75 ft |
| 8 | 14:50 | 120 | 121 ft |
| 9 | 15:09 | 121 | 108 ft |
| 10 | 13:55 | 120 | 75 ft |
| 11 | 14:12 | 112 | 7 ft |
| 12 | 14:53 | 123 | 115 ft |
| 13 | 15:04 | 126 | 79 ft |
| 14 | 14:52 | 128 | 72 ft |
| 15 | 14:53 | 128 | 66 ft |
| 16 | 14:09 | 125 | 20 ft |
| 17 | 16:13 | 129 | 141 ft |
| 18 | 14:54 | 129 | 62 ft |
| 19 | 14:08 | 132 | 33 ft |
| 20 | 14:41 | 127 | 33 ft |
| 21 | 15:34 | 130 | 72 ft |
| 22 | 14:26 | 131 | 7 ft |
| 23 | 16:01 | 130 | 92 ft |
| 24 | 14:10 | 130 | 0 ft |
| 25 | 15:37 | 132 | 0 ft |
| 26 | 15:52 | 134 | 102 ft |
| 0.30 | 15:05 | 133 | 20 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.