Threshold Run 25 min
A 20-minute tempo block at lactate threshold pace (Zone 4 ≈ 88–92% max HR), bracketed by warm-up and cool-down, that raises lactate clearance and VO2max.
A 20-minute tempo block at lactate threshold pace (Zone 4 ≈ 88–92% max HR), bracketed by 5-minute warm-up and cool-down, that raises lactate clearance and the VO2max ceiling in 25 minutes. The sustained threshold effort is the core stimulus of the session.
The session at a glance
- Focus: cardio-threshold
- Intensity: high
- Duration: 25 minutes
- Equipment: running-shoes
The protocol
- Warm-up — 5 min. easy jog.
- Tempo — 20 min. Zone 4, 88–92% max HR.
- Cool-down — 5 min. easy jog.
Why this works
- Lactate clearance. Holding pace right at lactate threshold trains the body to clear lactate faster.
- Drives aerobic ceiling. Sustained Zone 4 work raises the VO2max ceiling named in the description.
- Pace discipline. A continuous 20-minute tempo block builds the ability to hold threshold effort under fatigue.
How to scale it
- On tired days, shorten the tempo block from 20 to 12–15 minutes.
- Hold the lower end of the Zone 4 range (88% max HR) rather than skipping the session.
- Break the tempo into two segments with a short easy jog between if you can't hold pace continuously.
Related protocols
Sources
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