Intervalsconfidence 0.83
3 × 1km hills
Colin Dismuke50 km / marathon build
Source: own Strava export
Intervals
3 × 1km hills
Distance
9.5 km
Moving
46:29
Rep pace
4:05/km
Avg HR
161 bpm
Reps
3
Planned vs actual · TrainingPeaksPlanned 1:08:44 · 14.4 kmRan 46:29 · 9.5 kmIF 1.52TSS 178
Shape of the sessionEasyWorkFastest
warm up
cool down
0:003 × work / float46:29
The decode
This was a hill session combining steady uphill running with sub-threshold marathon-goal-pace work, repeated three times with jogs back down.
The three 4:00 reps progressed from 4:11/km to 4:03/km to 4:02/km. Heart rate was 176, 170 and 178, with 205 m of elevation gain across the session.
Rep splits
| Rep | Time | Pace | HR | Float |
|---|---|---|---|---|
| 1 | 4:00 | 4:11/km | 176 | 4:19 |
| 2 | 4:00 | 4:03/km | 170 | 4:01 |
| 3 | 4:00 | 4:02/km | 178 | 3:04 |
0.83
confidence
What the engine saw
- 3 work intervals detected from lap markers, confirmed by clear pace separation.
- Recoveries average 228s.
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
Recovery19%
Z2
Endurance13%
Z3
Tempo10%
Z4
Threshold35%
Z5
VO₂max23%
Pace
Z1
Easy64%
Z2
Endurance23%
Z3
Tempo12%
Z4
Threshold0%
Z5
VO₂max0%
Z6
Speed0%
Power
Z1
Recovery9%
Z2
Endurance33%
Z3
Tempo17%
Z4
Threshold25%
Z5
VO₂max15%
Z6
Anaerobic0%
Z7
Neuro0%
Aerobic decoupling · Pa:HR-7.4%
Effort & efficiency
0.70
Running effectiveness
speed per watt/kg, reps
5.8 w/kg
Power-to-weight
rep average
2.56
Efficiency factor
norm. power per bpm
1.07
Variability index
1.0 = perfectly even power
1.7%
Rep consistency
pace spread across reps, lower is tighter
1085 kJ
Total work
mechanical energy
709 kcal
Energy
estimated burn
799 bpk
Cardiac cost
heartbeats per km
58%
Above threshold
≥ 164 bpm (Z4+)
-0:24/km
Split balance
negative split, faster 2nd half
Conditions-adjusted pace30°C · +205 m
Actual
4:05/km
Grade-adjusted
4:05/km
Heat-adjusted
3:52/km
−13s/km
True effort
3:52/km
−13s/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.