Intervalsconfidence 0.83
3 × 1km hills
Colin Dismuke50 km / marathon build
Source: own Strava export
Intervals
3 × 1km hills
Distance
12.0 km
Moving
55:23
Rep pace
3:51/km
Avg HR
154 bpm
Reps
3
Planned vs actual · TrainingPeaksPlanned 1:10:16 · 15.2 kmRan 55:23 · 12.0 kmIF 1.57TSS 225
Shape of the sessionEasyWorkFastest
warm up
cool down
0:003 × work / float55:23
The decode
Three hill reps formed a strength-and-threshold session. The uphill running demanded a steady 6-7 RPE with controlled technique and leg turnover, followed by sub-threshold work at marathon-goal pace. Jog-back recoveries kept the session continuous rather than turning it into isolated flat reps.
The work held together and sharpened late: 3:54/km, 3:53/km, then 3:46/km, with heart rate rising from 171 to 181.
Rep splits
| Rep | Time | Pace | HR | Float |
|---|---|---|---|---|
| 1 | 3:53 | 3:54/km | 171 | 3:47 |
| 2 | 3:53 | 3:53/km | 175 | 3:13 |
| 3 | 3:46 | 3:46/km | 181 | 8:31 |
0.83
confidence
What the engine saw
- 3 work intervals detected from lap markers, confirmed by clear pace separation.
- Recoveries average 310s.
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
Recovery37%
Z2
Endurance18%
Z3
Tempo8%
Z4
Threshold19%
Z5
VO₂max18%
Pace
Z1
Easy52%
Z2
Endurance28%
Z3
Tempo18%
Z4
Threshold2%
Z5
VO₂max0%
Z6
Speed0%
Power
Z1
Recovery3%
Z2
Endurance27%
Z3
Tempo28%
Z4
Threshold30%
Z5
VO₂max9%
Z6
Anaerobic3%
Z7
Neuro0%
Aerobic decoupling · Pa:HR+5.9%
Effort & efficiency
0.73
Running effectiveness
speed per watt/kg, reps
6.0 w/kg
Power-to-weight
rep average
2.74
Efficiency factor
norm. power per bpm
1.06
Variability index
1.0 = perfectly even power
1.6%
Rep consistency
pace spread across reps, lower is tighter
1416 kJ
Total work
mechanical energy
864 kcal
Energy
estimated burn
761 bpk
Cardiac cost
heartbeats per km
37%
Above threshold
≥ 164 bpm (Z4+)
-0:19/km
Split balance
negative split, faster 2nd half
Conditions-adjusted pace33°C · +230 m
Actual
3:51/km
Grade-adjusted
3:51/km
Heat-adjusted
3:36/km
−15s/km
True effort
3:36/km
−15s/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.