Intervalsconfidence 0.83
Morning Run
Colin Dismuke50 km / marathon build
Source: own Strava export
Intervals
Morning Run
Distance
14.9 km
Moving
69:20
Rep pace
4:08/km
Avg HR
161 bpm
Reps
7
Shape of the sessionEasyWorkFastest
warm up
cool down
0:007 × work / float69:20
The decode
A seven-rep interval set was a cut-down progression rather than a fixed-pace block. The changing pace was the session's defining demand, with recoveries averaging 302s.
The work moved from 4:22/km to 3:47/km before the final 712 m at 4:07/km. Heart rate was uneven across the progression, reaching 183 on the 4:07/km rep before registering 155 at 3:58/km and 163 at 3:47/km.
Rep splits
| Rep | Time | Pace | HR | Float |
|---|---|---|---|---|
| 1 | 4:22 | 4:22/km | 160 | — |
| 2 | 4:14 | 4:14/km | 159 | 5:09 |
| 3 | 4:22 | 4:22/km | 170 | — |
| 4 | 4:07 | 4:07/km | 183 | 4:50 |
| 5 | 3:58 | 3:58/km | 155 | 5:05 |
| 6 | 3:47 | 3:47/km | 163 | — |
| 7 | 2:56 | 4:07/km | 164 | 5:02 |
0.83
confidence
What the engine saw
- 7 work intervals detected from lap markers, confirmed by clear pace separation.
- Rep paces descend across the set (a cut-down / progression).
- Recoveries average 302s.
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
Recovery4%
Z2
Endurance12%
Z3
Tempo36%
Z4
Threshold41%
Z5
VO₂max7%
Pace
Z1
Easy41%
Z2
Endurance25%
Z3
Tempo32%
Z4
Threshold2%
Z5
VO₂max0%
Z6
Speed0%
Power
Z1
Recovery4%
Z2
Endurance25%
Z3
Tempo23%
Z4
Threshold26%
Z5
VO₂max23%
Z6
Anaerobic0%
Z7
Neuro0%
Aerobic decoupling · Pa:HR-7%
Effort & efficiency
0.71
Running effectiveness
speed per watt/kg, reps
5.7 w/kg
Power-to-weight
rep average
2.57
Efficiency factor
norm. power per bpm
1.05
Variability index
1.0 = perfectly even power
4.8%
Rep consistency
pace spread across reps, lower is tighter
1952 kJ
Total work
mechanical energy
1071 kcal
Energy
estimated burn
867 bpk
Cardiac cost
heartbeats per km
48%
Above threshold
≥ 164 bpm (Z4+)
-0:16/km
Split balance
negative split, faster 2nd half
Conditions-adjusted pace21°C · +107 m
Actual
4:08/km
Grade-adjusted
4:08/km
Heat-adjusted
4:02/km
−6s/km
True effort
4:02/km
−6s/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.