Surging VO2max Intervals, 4 x 4.5 min
Four 4.5-minute blocks that alternate 30 seconds at 125 to 135% of FTP with 60 seconds at threshold, VO2max work with race-like surges.
- Duration
- 59 min
- Effort
- 57
- Level
- Advanced
- Focus zone
- Threshold
Your values
Targets relative to your threshold values. Enter your values to see absolute numbers.
| # | Step | Length | Target |
|---|---|---|---|
| 1 | Warm-upEndurance Easy spin, build gradually | 10 min | 45 → 72% FTP54 → 74% HRmax |
| 2 | Warm-upEndurance Steady and easy | 5 min | 60-70% FTP65-78% HRmax |
| 4 ×Repeat these steps | |||
| 3.1 | IntervalVO2max Surge | 30 s | 125-135% FTP92-98% HRmax |
| 3.2 | IntervalThreshold Hold threshold | 1 min | 100-105% FTP87-93% HRmax |
| 3.3 | IntervalVO2max Surge | 30 s | 125-135% FTP92-98% HRmax |
| 3.4 | IntervalThreshold Hold threshold | 1 min | 100-105% FTP87-93% HRmax |
| 3.5 | IntervalVO2max Last surge | 30 s | 125-135% FTP92-98% HRmax |
| 3.6 | IntervalThreshold Hold threshold to the end | 1 min | 100-105% FTP87-93% HRmax |
| 3.7 | RecoveryRecovery Easy spin | 4 min | 40-55% FTP50-65% HRmax |
| 4 | Cool-downRecovery Easy spin, let the legs settle | 10 min | 60 → 40% FTP65 → 50% HRmax |
About this workout
Each block contains three surges of 30 seconds at 125 to 135% of FTP, each followed by 60 seconds at 100 to 105%. You never drop below threshold during the block, so breathing stays deep and fast from the second surge on. Four blocks with 4 minutes of easy spinning between them give 18 minutes of work.
Varying the power inside the effort keeps oxygen uptake high, and the surges give the session a race-like feel. It reflects what happens in a breakaway or on a rolling course, where you hold a high steady effort and still have to answer accelerations.
The session suits experienced road and gravel riders in the build and peak phases. It is hard, so plan an easy day after it. If the 60 second parts drift below threshold in the last block, ride three blocks next time. Progress by adding a fourth surge to each block.
Tips
- Hit the surges with a quick rise in cadence instead of standing up.
- Settle the 60 second parts quickly at threshold, not below.
- Use ERG mode or a fixed gear for consistent surges.
Good forRoad raceGravel
Season phaseBuildPeak