Critical Speed Test 3 min and 12 min
Two all-out runs of 3 and 12 minutes with 30 minutes of recovery between them, to calculate your critical speed and D prime for training.
- Duration
- 1 h 18 min
- Distance
- 14.4 kmestimated
- Effort
- 93
- Level
- Advanced
- Focus zone
- VO2max
Your values
Targets relative to your threshold values. Enter your values to see absolute numbers.
100% is your threshold pace. Higher values are faster, lower values are slower.
| # | Step | Length | Target |
|---|---|---|---|
| 1 | Warm-upEndurance Easy 15 min | 15 min | 78-88% threshold pace68-78% HRmax72-82% FTP |
| 3 ×Repeat these steps | |||
| 2.1 | IntervalAnaerobic Stride | 20 s | 113-125% threshold pace92-100% HRmax113-130% FTP |
| 2.2 | RecoveryRecovery Walk or jog | 40 s | 70-78% threshold pace55-68% HRmax60-72% FTP |
| 3 | RecoveryRecovery Jog to the start | 2 min | 70-78% threshold pace55-68% HRmax60-72% FTP |
| 4 | IntervalAnaerobic 3 min all out, note distance | 3 min | 112-122% threshold pace92-100% HRmax113-130% FTP |
| 5 | RecoveryRecovery 30 min walk and easy jog | 30 min | 70-78% threshold pace55-68% HRmax60-72% FTP |
| 2 ×Repeat these steps | |||
| 6.1 | IntervalAnaerobic Stride | 20 s | 113-125% threshold pace92-100% HRmax113-130% FTP |
| 6.2 | RecoveryRecovery Walk or jog | 1 min | 70-78% threshold pace55-68% HRmax60-72% FTP |
| 7 | IntervalVO2max 12 min all out, note distance | 12 min | 105-110% threshold pace92-98% HRmax104-112% FTP |
| 8 | Cool-downRecovery Easy jog | 10 min | 70-78% threshold pace55-68% HRmax60-72% FTP |
About this workout
Critical speed marks the boundary between running you can sustain for a long time and running that leads to exhaustion within minutes. Sports scientists estimate it from two or more all-out efforts of different length. A 3 minute and a 12 minute effort in the same session, with 30 minutes of recovery between them, give a usable estimate.
Warm up for 15 minutes with strides. Run 3 minutes as far as you can and note the distance. Recover for 30 minutes with walking and easy jogging. Do a few strides, then run 12 minutes as far as you can and note the distance. Cool down for ten minutes. A track makes the distances easy to measure.
Critical speed is the 12 minute distance minus the 3 minute distance, divided by 540 seconds. For example, 3400 m and 1000 m give 4.44 m/s, or about 3:45 per km. It usually sits a little faster than threshold pace. D prime, the distance you can run above critical speed, is the 3 minute distance minus 180 times critical speed.
Tips
- Pace the 3 minute effort, it should be hard from the start but not a sprint.
- Keep moving during the 30 minute break so you stay warm.
- If one session is too much, run the two efforts on separate days within a week.
Origin
Based on the two time trial model of critical speed used in sports science research.
Good for5k10kHalf marathonTrackFTP
Season phaseBaseBuildAny time