Sweet spot training means riding at 88-93% of your FTP — the intensity band that sits just below threshold. It delivers close to the training stimulus of full threshold work with significantly less fatigue, which lets time-crunched cyclists accumulate more quality minutes per week. The trade-off: it won't push your VO2max ceiling, so it works best as one tool inside a polarised plan rather than your only hard session.
Sweet spot is one of the most debated topics in amateur cycling. Some coaches swear by it. Others say it's the grey zone dressed up in a marketing name. The truth, as with most things in cycling, is more nuanced than either camp admits.
What Sweet Spot Actually Is
Sweet spot sits between tempo (76-90% FTP) and threshold (91-105% FTP). The theory: it provides nearly the same training stimulus as threshold work but with significantly less fatigue, allowing you to accumulate more quality training time.
The name comes from the idea that it's the "sweet spot" between intensity and sustainability — the highest intensity you can hold for extended periods without the recovery cost of full threshold efforts.
When Sweet Spot Works Well
For time-crunched cyclists. If you can only train 6-8 hours per week, sweet spot lets you get a meaningful training stimulus in shorter sessions. A 2x20-minute sweet spot session in 60 minutes is more productive than a 60-minute Zone 2 ride for pushing threshold-related adaptations.
During the build phase. In the 8-12 weeks before a target event, sweet spot work builds the specific muscular endurance needed for sustained efforts. It's particularly effective for sportive and gran fondo preparation where you need to hold sub-threshold power for hours.
For intermediate cyclists. If you've been training less than 3 years and your FTP is still progressing, sweet spot provides a reliable training stimulus. Your body responds to a wider range of stimuli at this stage.
When Sweet Spot Doesn't Work
As your only high-intensity work. Sweet spot doesn't push your VO2max ceiling. If you never go above threshold, your FTP will eventually plateau because the ceiling above it hasn't moved. You need Zone 5 (VO2max work) to lift the ceiling.
Year-round without variation. Your body accommodates to repeated stimuli. If every hard session is 2x20 at sweet spot for 12 months, the training effect diminishes. Periodisation matters.
When you're already highly trained. Advanced cyclists (4+ W/kg) often find that sweet spot produces diminishing returns. At this level, the polarised model (80% easy, 20% very hard) tends to produce better outcomes. This is Professor Seiler's consistent finding across elite endurance athletes.
The Nuanced Position
Most experienced coaches don't hate sweet spot. They hate it when it's used as the default intensity for every session. The framework that works best for most amateur cyclists:
- Off-season: Mostly Zone 2 with some sweet spot to maintain fitness
- Base phase: Zone 2 foundation with 1-2 sweet spot sessions per week
- Build phase: Replace one sweet spot session with VO2max intervals
- Peak phase: Reduce sweet spot, increase race-specific intensity
Sweet spot is a tool. Like every tool, it works brilliantly when used in the right context and poorly when used for everything.
Key Takeaways
- Sweet spot (88-93% FTP) provides high training stimulus with moderate fatigue
- It works well for time-crunched cyclists and during build phases
- It does NOT replace VO2max work — you need both to keep progressing
- Year-round sweet spot leads to plateau — periodise your training
- Advanced cyclists (4+ W/kg) may benefit more from polarised training
- The best approach: use sweet spot as one tool in a periodised plan, not the entire plan
- Use our FTP Zone Calculator to find your exact sweet spot power range
- For a structured annual plan, see our periodisation guide
- If your FTP has stalled on sweet spot alone, read how to break through an FTP plateau
- Time-crunched riders benefit most — see our training with a job guide