Intervalsconfidence 0.83
6 × 1km
Colin Dismuke50 km / marathon build
Source: own Strava export
Intervals
6 × 1km
Distance
10.7 km
Moving
48:49
Rep pace
3:38/km
Avg HR
161 bpm
Reps
6
Planned vs actual · TrainingPeaksPlanned not setRan 48:49 · 10.7 kmIF 1.37TSS 152
Shape of the sessionEasyWorkFastest
warm up
cool down
0:006 × work / float48:49
The decode
Six 1km reps, with the odd-numbered reps harder, formed an alternating interval set. The pattern demanded repeated changes of intensity under wind and 33 C heat, making pace control part of the session rather than a by-product of it.
The harder reps ran 3:31, 3:27 and 3:34/km; the others were 3:44, 3:46 and 3:43/km. Heart rate reached 170, 175 and 179 on the harder reps, while the set stayed controlled through the final 3:43/km rep at 176.
Rep splits
| Rep | Time | Pace | HR | Float |
|---|---|---|---|---|
| 1 | 3:31 | 3:31/km | 170 | 1:16 |
| 2 | 3:44 | 3:44/km | 176 | 1:30 |
| 3 | 3:27 | 3:27/km | 175 | 1:26 |
| 4 | 3:46 | 3:46/km | 174 | 1:46 |
| 5 | 3:34 | 3:34/km | 179 | 1:41 |
| 6 | 3:43 | 3:43/km | 176 | 1:31 |
0.83
confidence
What the engine saw
- 6 work intervals detected from lap markers, confirmed by clear pace separation.
- Recoveries average 92s.
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
Endurance33%
Z3
Tempo7%
Z4
Threshold12%
Z5
VO₂max32%
Pace
Z1
Easy47%
Z2
Endurance12%
Z3
Tempo16%
Z4
Threshold16%
Z5
VO₂max10%
Z6
Speed0%
Power
Z1
Recovery8%
Z2
Endurance29%
Z3
Tempo16%
Z4
Threshold30%
Z5
VO₂max16%
Z6
Anaerobic1%
Z7
Neuro0%
Aerobic decoupling · Pa:HR+13.8%
Effort & efficiency
0.74
Running effectiveness
speed per watt/kg, reps
6.2 w/kg
Power-to-weight
rep average
2.59
Efficiency factor
norm. power per bpm
1.08
Variability index
1.0 = perfectly even power
3.3%
Rep consistency
pace spread across reps, lower is tighter
1188 kJ
Total work
mechanical energy
759 kcal
Energy
estimated burn
759 bpk
Cardiac cost
heartbeats per km
45%
Above threshold
≥ 164 bpm (Z4+)
+0:22/km
Split balance
positive split, slower 2nd half
Conditions-adjusted pace33°C · +74 m
Actual
3:37/km
Grade-adjusted
3:37/km
Heat-adjusted
3:23/km
−14s/km
True effort
3:23/km
−14s/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.