Intervalsconfidence 0.83
3 × 500m hills
Colin Dismuke50 km / marathon build
Source: own Strava export
Intervals
3 × 500m hills
Distance
11.5 km
Moving
48:54
Rep pace
3:35/km
Avg HR
158 bpm
Reps
3
Planned vs actual · TrainingPeaksPlanned 49:31 · 11.5 kmRan 48:54 · 11.5 kmIF 1.39TSS 156
Shape of the sessionEasyWorkFastest
warm up
cool down
0:003 × work / float48:54
The decode
A 3 × 2k threshold set with 500m kicks was a lactate-loading session that demanded threshold pace after faster running. The final kick finished uphill, adding a strength component to the closing effort.
The threshold blocks stayed close to the prescribed 3:57/km, while the kicks ran 3:34/km, 3:35/km and 3:37/km. Heart rate rose from 170 to 182 across the kicks; the final uphill 500m slowed without breaking the pattern.
Rep splits
| Rep | Time | Pace | HR | Float |
|---|---|---|---|---|
| 1 | 1:47 | 3:34/km | 170 | 3:57 |
| 2 | 1:47 | 3:35/km | 176 | 3:54 |
| 3 | 1:49 | 3:37/km | 182 | 4:46 |
0.83
confidence
What the engine saw
- 3 work intervals detected from lap markers, confirmed by clear pace separation.
- Recoveries average 252s.
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
Recovery15%
Z2
Endurance21%
Z3
Tempo20%
Z4
Threshold29%
Z5
VO₂max14%
Pace
Z1
Easy39%
Z2
Endurance11%
Z3
Tempo42%
Z4
Threshold7%
Z5
VO₂max0%
Z6
Speed0%
Power
Z1
Recovery0%
Z2
Endurance16%
Z3
Tempo41%
Z4
Threshold31%
Z5
VO₂max12%
Z6
Anaerobic0%
Z7
Neuro0%
Aerobic decoupling · Pa:HR+6.3%
Effort & efficiency
0.80
Running effectiveness
speed per watt/kg, reps
5.8 w/kg
Power-to-weight
rep average
2.70
Efficiency factor
norm. power per bpm
1.03
Variability index
1.0 = perfectly even power
0.7%
Rep consistency
pace spread across reps, lower is tighter
1380 kJ
Total work
mechanical energy
784 kcal
Energy
estimated burn
771 bpk
Cardiac cost
heartbeats per km
43%
Above threshold
≥ 164 bpm (Z4+)
-0:13/km
Split balance
negative split, faster 2nd half
Conditions-adjusted pace35°C · +80 m
Actual
3:35/km
Grade-adjusted
3:35/km
Heat-adjusted
3:19/km
−16s/km
True effort
3:19/km
−16s/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.