Intervalsconfidence 0.83
5 × 300m
Colin Dismuke50 km / marathon build
Source: own Strava export
Intervals
5 × 300m
Distance
17.2 km
Moving
70:44
Rep pace
3:13/km
Avg HR
166 bpm
Reps
5
Planned vs actual · TrainingPeaksPlanned 19.0 kmRan 1:10:44 · 17.2 kmIF 1.47TSS 251
Shape of the sessionEasyWorkFastest
warm up
cool down
0:005 × work / float70:44
The decode
Five one-minute hard reps preceded progressive sustained work in a marathon-specific progression. The short reps made the later sustained work arrive under load, while the faster second block demanded progression rather than simple repetition.
The first four reps stayed between 3:03/km and 3:12/km before the fifth fell to 3:29/km. Heart rate rose from 168 on the opening reps to 173 on the fifth, while the longer work progressed from 4:00/km at HR 170 to 3:44/km at HR 178.
Rep splits
| Rep | Time | Pace | HR | Float |
|---|---|---|---|---|
| 1 | 1:00 | 3:03/km | 168 | 1:00 |
| 2 | 1:00 | 3:12/km | 168 | 1:00 |
| 3 | 1:00 | 3:10/km | 170 | 1:00 |
| 4 | 1:00 | 3:12/km | 172 | 1:00 |
| 5 | 1:00 | 3:29/km | 173 | 1:00 |
0.83
confidence
What the engine saw
- 5 work intervals detected from lap markers, confirmed by clear pace separation.
- Recoveries average 60s.
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
Recovery8%
Z2
Endurance7%
Z3
Tempo15%
Z4
Threshold28%
Z5
VO₂max42%
Pace
Z1
Easy18%
Z2
Endurance20%
Z3
Tempo51%
Z4
Threshold8%
Z5
VO₂max3%
Z6
Speed1%
Power
Z1
Recovery0%
Z2
Endurance9%
Z3
Tempo29%
Z4
Threshold43%
Z5
VO₂max13%
Z6
Anaerobic5%
Z7
Neuro0%
Aerobic decoupling · Pa:HR+1%
Effort & efficiency
0.73
Running effectiveness
speed per watt/kg, reps
7.1 w/kg
Power-to-weight
rep average
2.69
Efficiency factor
norm. power per bpm
1.04
Variability index
1.0 = perfectly even power
4.4%
Rep consistency
pace spread across reps, lower is tighter
2065 kJ
Total work
mechanical energy
1196 kcal
Energy
estimated burn
772 bpk
Cardiac cost
heartbeats per km
70%
Above threshold
≥ 164 bpm (Z4+)
-0:17/km
Split balance
negative split, faster 2nd half
Conditions-adjusted pace27°C · +183 m
Actual
3:13/km
Grade-adjusted
3:13/km
Heat-adjusted
3:04/km
−9s/km
True effort
3:04/km
−9s/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.