Intervalsconfidence 0.83
5 × 300m
Colin Dismuke50 km / marathon build
Source: own Strava export
Intervals
5 × 300m
Distance
17.3 km
Moving
73:04
Rep pace
3:21/km
Avg HR
171 bpm
Reps
5
Planned vs actual · TrainingPeaksPlanned 1:10:00Ran 1:13:04 · 17.3 kmIF 1.52TSS 282
Shape of the sessionEasyWorkFastest
warm up
cool down
0:005 × work / float73:04
The decode
This was a steady segment, 5 × 1-minute hard/float repetitions, and a 10-minute threshold block. The equal one-minute hard and float blocks demanded repeated speed changes, while the threshold block added sustained work after the faster running.
The hard-minute paces ranged from 3:16/km to 3:26/km, while HR declined from 187 to 168 before ending at 169; the 10-minute threshold block was 3:39/km at HR 172.
Rep splits
| Rep | Time | Pace | HR | Float |
|---|---|---|---|---|
| 1 | 1:00 | 3:16/km | 187 | 1:00 |
| 2 | 1:00 | 3:24/km | 183 | 1:00 |
| 3 | 1:00 | 3:17/km | 175 | 1:00 |
| 4 | 1:00 | 3:26/km | 168 | 1:00 |
| 5 | 1:00 | 3:23/km | 169 | 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
Recovery2%
Z2
Endurance4%
Z3
Tempo27%
Z4
Threshold26%
Z5
VO₂max41%
Pace
Z1
Easy14%
Z2
Endurance48%
Z3
Tempo29%
Z4
Threshold7%
Z5
VO₂max1%
Z6
Speed0%
Power
Z1
Recovery0%
Z2
Endurance2%
Z3
Tempo58%
Z4
Threshold36%
Z5
VO₂max3%
Z6
Anaerobic0%
Z7
Neuro0%
Aerobic decoupling · Pa:HR-11.4%
Effort & efficiency
0.82
Running effectiveness
speed per watt/kg, reps
6.0 w/kg
Power-to-weight
rep average
2.43
Efficiency factor
norm. power per bpm
1.02
Variability index
1.0 = perfectly even power
2.1%
Rep consistency
pace spread across reps, lower is tighter
1827 kJ
Total work
mechanical energy
1242 kcal
Energy
estimated burn
737 bpk
Cardiac cost
heartbeats per km
67%
Above threshold
≥ 164 bpm (Z4+)
-0:23/km
Split balance
negative split, faster 2nd half
Conditions-adjusted pace18°C · +51 m
Actual
3:21/km
Grade-adjusted
3:21/km
Heat-adjusted
3:19/km
−2s/km
True effort
3:19/km
−2s/km
The rep pace re-expressed for flat ground and cool air, the effort, not the clock. Adjustments are modest on this one; on a hot day or a hilly route this is where the real work hides.