How to Increase Cycling Power: Interval Training
Learn how to increase cycling power with progressive threshold and VO2max intervals, sensible weekly placement, and enough recovery to adapt.
Intervals break hard work into repeatable efforts separated by easy recovery. That lets you spend useful time at a demanding intensity without fading through one long effort. They matter most in the build and peak phases, once regular endurance training is in place.
Threshold intervals
Threshold intervals develop the power you can sustain for long efforts. A session might use three or four repeats of eight to twelve minutes near FTP, with easy spinning between. Pace the first interval so the last is just as strong.
VO2max intervals
VO2max sessions use shorter, harder efforts, such as five three-minute repeats with equal recovery. Start fresh, commit to the work, and leave easy days before the next demanding session. One VO2max workout a week is enough for many riders.
Protect the easy days
Intervals work only when you can ride them well and recover afterward. Keep the surrounding endurance and recovery rides genuinely easy. Most riders progress with one or two focused sessions a week; adding more often lowers the quality of all of them.
Start with the adaptation, then choose the workout
An interval format is a tool. Threshold work aims to extend sustainable high aerobic output and fatigue resistance. VO₂max work tries to accumulate time with very high oxygen demand. Anaerobic sessions develop a different capacity again. Choosing 4 × 8 minutes because it looks hard is backwards; decide which capacity limits the goal, then select an interval duration, intensity, recovery, and total work that targets it.
| Goal | Example starting session | Recovery | Execution cue |
|---|---|---|---|
| Tempo / muscular endurance | 2 × 20 min at 80–88% FTP | 5 min easy | Controlled breathing; finish with reserve |
| Threshold | 3 × 10 min at 95–100% FTP | 5 min easy | Even power; last repeat resembles the first |
| VO₂max | 5 × 3 min at roughly 110–120% FTP | 3 min easy | Very hard but repeatable; power may vary by rider |
| Short VO₂ / aerobic power | 3 sets of 8 × 30 s hard / 30 s easy | 4 min between sets | Do not sprint the first repetitions |
| Anaerobic capacity | 6 × 45 s very hard | 4–5 min easy | High quality with near-full recovery |
The percentages are starting ranges, not pass-fail scores. For VO₂max work especially, the output that creates a productive severe-intensity session differs with the rider's power-duration profile. Breathing, repeatability, and the drop from first to last interval help judge whether the dose matched the goal.
Progress duration before intensity
A durable progression increases useful work while preserving execution. For threshold training, a rider might move from 3 × 8 minutes to 3 × 10, then 3 × 12, before raising target power. For VO₂max, progressing from 5 × 3 minutes to 6 × 3 or 5 × 4 can be effective, but only if the later intervals remain purposeful. More suffering is not automatically more stimulus.
Four-week threshold example
- Week 1: 3 × 8 minutes at a controlled 95–100% FTP; 4 minutes recovery.
- Week 2: 3 × 10 minutes at the same working range; 5 minutes recovery.
- Week 3: 3 × 12 minutes, lowering power slightly if needed to preserve pacing.
- Week 4: reduced load—2 × 8 minutes or endurance only, depending on fatigue.
Place hard sessions where they can succeed
Many recreational riders can absorb two demanding cycling sessions per week when they are separated by at least one easier day. Strength training, racing, hard group rides, and long rides with substantial climbing also count as stress. A Tuesday threshold session and Saturday VO₂max session may work; Tuesday threshold, Thursday group ride, Saturday race, and Sunday long ride is not a two-hard-day week.
Know when to stop an interval session
- Stop when power falls sharply and cannot recover despite appropriate pacing.
- Stop for chest pain, faintness, unusual breathlessness, or symptoms that feel medically concerning.
- Modify when technique breaks down or pain changes your movement.
- Do not add repetitions merely because the first prescribed number is complete; the planned dose already includes recovery cost.
Frequently asked questions
How many interval sessions should cyclists do each week?
One or two is enough for many recreational cyclists. The right number depends on training history, total volume, strength work, racing, and recovery—not just motivation.
Should every interval hit the exact same wattage?
No. Stable execution is useful, but terrain, fatigue, protocol, and the intended energy system affect power. Use a range and preserve the purpose of the session.
Are longer VO₂max intervals always better?
No. Longer repetitions can accumulate oxygen demand, but only when intensity and repeatability are appropriate. Shorter formats may suit some riders or phases better.
Evidence and further reading
FTP500 distinguishes established findings from practical coaching conventions. These sources informed this guide:
- Odden et al. (2024), Fraction of VO₂max during interval training and cycling performance gainCyclist intervention linking the internal intensity reached during intervals with subsequent performance changes.
- Seiler (2010), Best practice for endurance training intensity and duration distributionContext for combining a predominance of low-intensity work with a limited number of intensive sessions.