Ask ten cyclists how many training zones there are and you'll get at least four different answers. Some will say five, some will say seven, a few will insist that three is the only number that matters, and one will look you dead in the eye and say "I just ride by feel." The confusion is real — and for most amateur riders, it gets in the way of actually training well.
Here's what's worth understanding: the zone number is almost irrelevant. What matters is identifying the physiological boundaries that define meaningfully different types of effort, then training at the right intensity for the right duration on the right day. The zone model is just a map. And like any map, it's only useful if you know where you are.
Why zone models exist — and why they disagree
Training zones emerged from sports science research trying to link specific exercise intensities to specific physiological responses. Ride below your first ventilatory threshold and your body relies predominantly on fat oxidation, clears lactate efficiently, and can sustain the effort for hours. Push above your second ventilatory threshold — commonly called FTP or functional threshold — and lactate accumulates faster than your body can clear it. You're now working on borrowed time. The space in between these two thresholds is where most of the disagreement lives.
The 3-zone model, popularised by Norwegian researchers and embedded in how elite endurance coaches like Seiler structure training, draws clean lines around those two physiological thresholds. Everything below threshold one is Zone 1. The band between the two thresholds — often called "tempo" or "sweet spot" territory — is Zone 2. Above the second threshold is Zone 3. Simple, physiologically grounded, hard to misuse. The 5- and 7-zone models subdivide this same spectrum into finer slices. Coggan's 7-zone system breaks things down as far as neuromuscular power (Zone 7) and separates aerobic endurance from tempo from threshold from VO2max intervals. More zones means more precision in writing workouts — but also more opportunities to train in the wrong zone and not notice.
A 2024 survey of 778 endurance practitioners published in Scientific Reports found that 47% use a 5-zone system, while significant regional variation exists — Norwegian athletes skewed heavily toward the 3-zone model, which makes sense given that country's outsized influence on polarized training research. The honest conclusion: no single model is universally correct. The best one is whichever you'll actually use consistently.
Finding your anchors: the tests that actually matter
Every zone model, regardless of how many zones it uses, is anchored to physiological thresholds — most commonly your FTP (functional threshold power) and, if you're training by heart rate, your lactate threshold heart rate. The zones are just percentages or ranges derived from these numbers. Get the anchor wrong and every zone in your system is wrong too.
The most common way to estimate FTP is a 20-minute maximal effort test: ride as hard as you can sustain for 20 minutes, take 95% of that average power, and call it your FTP. It's not perfect — some riders have a natural ability to pace 20-minute efforts that inflates their result, others fall apart and underestimate — but it's accessible, repeatable, and good enough to work from. The ramp test, used by platforms like Zwift and TrainerRoad, has you increase power every minute until failure and estimates your FTP from your peak one-minute power. It tends to favour riders with a higher VO2max and can overestimate FTP for pure diesel engines. Pick whichever format you'll actually do, be consistent, and retest every 6–8 weeks or whenever your fitness changes meaningfully.
Heart rate zones are trickier. Your heart rate drifts with heat, hydration, caffeine, sleep quality, and accumulated fatigue — so a zone 2 ride that looks like zone 2 on paper might actually feel like zone 3 after a hard training block. That's not a reason to abandon heart rate — it's a reason to treat it as a signal, not a law. When in doubt, feel matters. If your "easy" ride feels harder than it should, it probably is.
If you're training with LeCoach, your zones can be set directly from your FTP and the system will flag when sessions drift outside their intended intensity — which removes a lot of the guesswork from day-to-day execution.
What actually happens in each zone
Rather than memorising a table of percentages, it's more useful to understand what your body is doing at each intensity and why that matters for adaptation. Zone 1 — recovery pace, genuinely easy, conversational without effort — does more than just "flush out lactate." It builds capillary density, improves mitochondrial efficiency, and keeps training volume high without adding meaningful fatigue. The problem is that most cyclists ride it too hard. If you can't hold a sentence without pausing, you're not in Zone 1.
Zone 2, in the 3-zone model, covers a wide swathe of the aerobic spectrum including what many 5- and 7-zone users would call "endurance," "tempo," and "sweet spot." This is where the conflation gets messy. True aerobic base work — the kind that builds the engine — lives at the lower end of this band, around 60–75% of FTP. Sweet spot training, the 88–93% FTP range beloved by time-crunched cyclists, sits near the top. Both sit "between the thresholds" but they're not the same stimulus. Sweet spot accumulates fatigue faster and requires more recovery; true base work does not. The sweet spot training article on this blog covers that distinction in detail.
Above threshold — Zone 3 in the 3-zone model, Zones 5 through 7 in Coggan — is where VO2max intervals, short sprint efforts, and neuromuscular work live. These sessions are expensive: they produce strong adaptation signals but require 48–72 hours of recovery to absorb properly. Time-crunched riders especially should treat high-intensity sessions as assets to be budgeted, not exercises to be collected.
The mistake most amateur cyclists make with zones
Let's be direct about this: the most common training mistake among amateur cyclists is not training too easy or too hard in isolation — it's doing everything at a moderate, sustainable, medium-hard intensity that sits between meaningful adaptations. It's comfortable enough to sustain for hours, hard enough to generate fatigue, but not hard enough to drive the adaptations that actually move fitness. In the 3-zone model, it lives squarely in Zone 2 — the grey zone that's genuinely difficult to make productive.
This is where zone awareness pays off. If you know your thresholds, you can deliberately structure sessions to fall clearly on one side or the other. Easy rides should be genuinely easy — you should finish them feeling like you held something back. Hard sessions should be genuinely hard — structured intervals at VO2max or threshold that leave you needing the next day to recover. The messy middle is fine occasionally, on long sportive rides or group rides where pace varies, but it shouldn't dominate your week.
A 2023 analysis of power distribution during the Tour de France, published in the Journal of Applied Physiology, showed that even professional riders spend the vast majority of race time at relatively low intensities — the high-intensity efforts are concentrated, decisive, and infrequent. That distribution isn't an accident. It's what the physiology demands.
A practical starting point
If you've never formally tested or set your zones, start here. Do a 20-minute FTP test after a proper warm-up. Take 95% of your average power as your working FTP. Use a simple 5-zone model: Zone 1 is below 55% of FTP, Zone 2 is 55–75%, Zone 3 is 75–90%, Zone 4 is 90–105%, Zone 5 is above 105%. Calibrate heart rate ranges by riding each zone and noting your heart rate once it stabilises — this gives you a feel-based cross-reference that's useful when power data isn't available or reliable.
Then use those zones deliberately. Not obsessively — you don't need to stare at your power numbers every 30 seconds — but intentionally. Know which zone a session is supposed to be in before you start. Check in periodically to see if you're close. And accept that some days your zones will feel harder than the numbers suggest. That's information too: it usually means you haven't recovered from the previous session, which tells you something useful about how you're managing your training load.
Zones are a tool for self-knowledge as much as a prescription. The more honestly you use them, the more clearly you'll understand what kind of training your body responds to — and that's the kind of insight that compounds over seasons.
Sources
Schlenker, M., et al. (2024). "Relationship of Cycling Power and Non-Linear Heart Rate Variability from Everyday Workout Data." Sensors, 24(14), 4468. Read study
Sylta, Ø., et al. (2025). "Individual training prescribed by heart rate variability, heart rate and well-being scores in experienced cyclists." Scientific Reports. Read study
Coggan, A., et al. (2023). "Intensity zone distributions during the 2023 Tour de France." Journal of Applied Physiology. Read study