Intervalsconfidence 0.83
3 × 1.7km
Colin Dismuke50 km / marathon build
Source: own Strava export
Intervals
3 × 1.7km
Distance
24.7 km
Moving
118:11
Rep pace
3:47/km
Avg HR
141 bpm
Reps
3
Planned vs actual · TrainingPeaksPlanned 24.0 kmRan 1:58:11 · 24.7 kmIF 1.48TSS 429
Shape of the sessionEasyWorkFastest
warm up
cool down
0:003 × work / float118:11
The decode
It was a long-run session with three 6:30 intervals, using 2:00 recoveries between the first and second reps and between the second and third.
The work accelerated from 3:53/km to 3:50/km to 3:39/km. Heart rate was 148, 168 and 146, while the final interval covered 1785 m. The session finished with 8:42 at 5:34/km.
Rep splits
| Rep | Time | Pace | HR | Float |
|---|---|---|---|---|
| 1 | 6:30 | 3:53/km | 148 | 2:00 |
| 2 | 6:30 | 3:50/km | 168 | 2:00 |
| 3 | 6:30 | 3:39/km | 146 | 8:42 |
0.83
confidence
What the engine saw
- 3 work intervals detected from lap markers, confirmed by clear pace separation.
- Recoveries average 254s.
Calibration flags
- Running power threshold estimated from the athlete's half-marathon best efforts (60-min power 476 W, 95% of 20-min power 460 W). Treat power zones and load as ±3%.
- Zones and running threshold are one snapshot, read 2 Jul 2026 and applied to every session in the archive. An older session is scored against today's zones, not the zones the athlete trained with then.
Engine read · editorial decode by Splits
Time in zone
Heart rate
Z1
Recovery54%
Z2
Endurance31%
Z3
Tempo10%
Z4
Threshold5%
Z5
VO₂max1%
Pace
Z1
Easy57%
Z2
Endurance28%
Z3
Tempo12%
Z4
Threshold2%
Z5
VO₂max0%
Z6
Speed0%
Power
Z1
Recovery5%
Z2
Endurance27%
Z3
Tempo31%
Z4
Threshold28%
Z5
VO₂max10%
Z6
Anaerobic0%
Z7
Neuro0%
Aerobic decoupling · Pa:HR+1.2%
Effort & efficiency
0.72
Running effectiveness
speed per watt/kg, reps
6.1 w/kg
Power-to-weight
rep average
2.87
Efficiency factor
norm. power per bpm
1.06
Variability index
1.0 = perfectly even power
2.7%
Rep consistency
pace spread across reps, lower is tighter
3081 kJ
Total work
mechanical energy
1682 kcal
Energy
estimated burn
758 bpk
Cardiac cost
heartbeats per km
5%
Above threshold
≥ 164 bpm (Z4+)
-0:24/km
Split balance
negative split, faster 2nd half
Conditions-adjusted pace21°C · +228 m
Actual
3:47/km
Grade-adjusted
3:47/km
Heat-adjusted
3:42/km
−5s/km
True effort
3:42/km
−5s/km
The rep pace re-expressed for flat ground and cool air, the effort, not the clock. The gap between actual and true effort is the day's hidden work: conditions were taxing the clock.