Intervalsconfidence 0.83
6 × 1km hills
Colin Dismuke50 km / marathon build
Source: own Strava export
Intervals
6 × 1km hills
Distance
13.1 km
Moving
63:26
Rep pace
4:18/km
Avg HR
139 bpm
Reps
6
Planned vs actual · TrainingPeaksPlanned 1:05:49 · 14.0 kmRan 1:03:26 · 13.1 kmIF 1.48TSS 230
Shape of the sessionEasyWorkFastest
warm up
cool down
0:006 × work / float63:26
The decode
This was a six-repetition hill-strength session: 1km uphill repeats on a 5-6% grade with easy downhill recoveries, progressing from steady to stronger to hard.
The reps ran in 4:34/km, 4:21/km, 4:09/km, 4:29/km, 4:19/km and 3:56/km. Heart rate reached 157 on the final rep, after 133 and 134 on reps four and five; the first five recoveries were 5:07, 5:06, 5:06, 5:11 and 5:06.
Rep splits
| Rep | Time | Pace | HR | Float |
|---|---|---|---|---|
| 1 | 4:34 | 4:34/km | 146 | 5:07 |
| 2 | 4:21 | 4:21/km | 149 | 5:06 |
| 3 | 4:09 | 4:09/km | 144 | 5:06 |
| 4 | 4:29 | 4:29/km | 133 | 5:11 |
| 5 | 4:19 | 4:19/km | 134 | 5:06 |
| 6 | 3:56 | 3:56/km | 157 | 0:21 |
0.83
confidence
What the engine saw
- 6 work intervals detected from lap markers, confirmed by clear pace separation.
- Rep paces descend across the set (a cut-down / progression).
- Recoveries average 259s.
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
Recovery66%
Z2
Endurance29%
Z3
Tempo4%
Z4
Threshold1%
Z5
VO₂max0%
Pace
Z1
Easy64%
Z2
Endurance27%
Z3
Tempo9%
Z4
Threshold0%
Z5
VO₂max0%
Z6
Speed0%
Power
Z1
Recovery4%
Z2
Endurance51%
Z3
Tempo16%
Z4
Threshold14%
Z5
VO₂max13%
Z6
Anaerobic2%
Z7
Neuro0%
Aerobic decoupling · Pa:HR-9.8%
Effort & efficiency
0.65
Running effectiveness
speed per watt/kg, reps
6.0 w/kg
Power-to-weight
rep average
2.87
Efficiency factor
norm. power per bpm
1.08
Variability index
1.0 = perfectly even power
4.9%
Rep consistency
pace spread across reps, lower is tighter
1455 kJ
Total work
mechanical energy
896 kcal
Energy
estimated burn
700 bpk
Cardiac cost
heartbeats per km
1%
Above threshold
≥ 164 bpm (Z4+)
-0:33/km
Split balance
negative split, faster 2nd half
Conditions-adjusted pace23°C · +184 m
Actual
4:17/km
Grade-adjusted
4:17/km
Heat-adjusted
4:09/km
−8s/km
True effort
4:09/km
−8s/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.