Intervalsconfidence 0.83
Hills and Threshold
Colin Dismuke50 km / marathon build
Source: own Strava export
Intervals
Hills and Threshold
Distance
11.8 km
Moving
53:21
Rep pace
3:37/km
Avg HR
136 bpm
Reps
3
Planned vs actual · TrainingPeaksPlanned 1:06:24 · 14.2 kmRan 53:21 · 11.8 kmIF 1.46TSS 187
Shape of the sessionEasyWorkFastest
warm up
cool down
0:003 × work / float53:21
The decode
This was a hill session combining steady uphill running with threshold work at the top, repeated three times with jogs back down. The structure targeted strength and technique on the climbs, followed by controlled threshold running.
The three detected work intervals lasted 3:00 each and progressed from 3:41/km to 3:38/km to 3:33/km. Heart rate stayed at 143, 144 and 144, while the recoveries were 3:36, 3:40 and 3:29.
Rep splits
| Rep | Time | Pace | HR | Float |
|---|---|---|---|---|
| 1 | 3:00 | 3:41/km | 143 | 3:36 |
| 2 | 3:00 | 3:38/km | 144 | 3:40 |
| 3 | 3:00 | 3:33/km | 144 | 3:29 |
0.83
confidence
What the engine saw
- 3 work intervals detected from lap markers, confirmed by clear pace separation.
- Recoveries average 215s.
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
Recovery64%
Z2
Endurance36%
Z3
Tempo0%
Z4
Threshold0%
Z5
VO₂max0%
Pace
Z1
Easy50%
Z2
Endurance33%
Z3
Tempo6%
Z4
Threshold11%
Z5
VO₂max0%
Z6
Speed0%
Power
Z1
Recovery3%
Z2
Endurance35%
Z3
Tempo16%
Z4
Threshold22%
Z5
VO₂max16%
Z6
Anaerobic8%
Z7
Neuro0%
Aerobic decoupling · Pa:HR+2.9%
Effort & efficiency
0.71
Running effectiveness
speed per watt/kg, reps
6.5 w/kg
Power-to-weight
rep average
3.25
Efficiency factor
norm. power per bpm
1.08
Variability index
1.0 = perfectly even power
1.5%
Rep consistency
pace spread across reps, lower is tighter
1355 kJ
Total work
mechanical energy
733 kcal
Energy
estimated burn
637 bpk
Cardiac cost
heartbeats per km
0%
Above threshold
≥ 164 bpm (Z4+)
-0:23/km
Split balance
negative split, faster 2nd half
Conditions-adjusted pace23°C · +210 m
Actual
3:37/km
Grade-adjusted
3:37/km
Heat-adjusted
3:30/km
−7s/km
True effort
3:30/km
−7s/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.