Zone 2 training means riding at a steady, easy endurance pace, usually 56–75% of your FTP in power terms. It’s the low-intensity riding that makes up most of the training of elite endurance athletes. Done right, it builds the aerobic base your harder workouts sit on, without piling on fatigue.
What “zone 2” actually means
“Zone 2” is one of the most used and least consistent terms in cycling. What it refers to depends on which zone system you use.
In Andrew Coggan’s seven-level power system, level 2 is Endurance: 56–75% of your functional threshold power (FTP), described as “all day” pace with low leg fatigue (Coggan, 2016). In WattAscent, this is the Endurance zone, with the same 56–75% range. Our power zones guide shows all eight zones.
Research on endurance athletes often uses a simpler three-zone model built on physiological thresholds. In that research, “low intensity” refers to training at around 2 mM blood lactate, below the first threshold (Seiler, 2010). Heart rate systems with five zones draw the lines in other places again.
The practical takeaway: when someone says “zone 2,” ask which system. For a cyclist training with power, it’s your Endurance zone.
Why zone 2 matters: what the research says
Elite endurance athletes do mostly easy training
Stephen Seiler’s influential 2010 review looked at how nationally and internationally competitive endurance athletes actually train. Athletes training 10 to 13 times a week did about 80% of their sessions at low intensity, with about 20% dominated by high-intensity work (Seiler, 2010).
Seiler also noted that athletes seem to “self-organize toward a high-volume training approach” (Seiler, 2010). His review found no convincing evidence that adding more high-intensity intervals improved long-term performance in athletes who were already well trained.
A later review of well-trained and elite athletes found that most studies report a “pyramidal” pattern: lots of low-intensity work, less moderate work, and the least high-intensity work. World-class athletes appear to use a “polarized” pattern instead, with plenty of easy and hard training and little in between (Stöggl & Sperlich, 2015).
Easy riding works best alongside hard riding
Zone 2 isn’t the whole story. In a 9-week trial with 48 well-trained endurance athletes, including cyclists, a polarized program (about 68% low intensity, 6% threshold and 26% high intensity) produced the biggest gains. VO2peak rose 11.7% and time to exhaustion 17.4% (Stöggl & Sperlich, 2014).
The group that did mostly low-intensity, high-volume training (83% low intensity) didn’t see those gains (Stöggl & Sperlich, 2014). Easy riding is the foundation, not a substitute for hard sessions.
A 2019 meta-analysis also found a moderate edge for polarized over threshold-focused training, but it rested on only three small trials of low quality (2019 meta-analysis). The research supports a mostly easy approach. It doesn’t settle the exact best split.
What easy riding does, and doesn’t, do
Continuous moderate-intensity training does raise your muscles’ mitochondrial content, the machinery that produces energy aerobically. But it isn’t uniquely good at it. A major review found that interval training can match or beat it for mitochondrial gains and VO2max improvement per unit of training (MacInnis & Gibala, 2017).
So why ride zone 2 at all? Because you can do a lot of it and still recover for your hard days. Seiler suggests that mostly long, easy training and a few very hard sessions complement each other at a stress level athletes can sustain (Seiler, 2010).
You’ll see bolder claims about zone 2 online. Stick to what it reliably gives you: aerobic volume you can recover from.
How to ride zone 2 indoors
Indoor riding is a great way to do zone 2, because nothing pulls you out of it. No hills, no traffic lights, no faster friends.
Use ERG mode
In ERG mode, your smart trainer holds the target power for you, whatever your cadence. For zone 2, set a target in the lower-to-middle part of your Endurance range and let the trainer hold it. WattAscent workouts set these targets from your FTP automatically.
Keep a natural cadence
Ride at a cadence that feels smooth. As a rule of thumb, WattAscent suggests 85–95 rpm for flat-road riding, which suits steady indoor work. Grinding a very low cadence or spinning very high makes an easy ride feel harder than it should.
Get airflow
Indoors you don’t have the wind you get outside, so you heat up fast. Use a strong fan pointed at you, and drink regularly, so an easy ride stays easy.
Keep it truly easy
Coggan describes level 2 as a low perceived effort where leg fatigue stays low (Coggan, 2016). By contrast, at Tempo, the next zone up, conversation becomes halting. If you couldn’t hold a normal conversation, you’re riding too hard.
Watch for heart-rate drift
On long rides your heart rate can creep up even if your power stays the same. This is cardiovascular drift: during prolonged exercise, stroke volume falls while heart rate rises (Souissi et al., 2021). If you train by heart rate, expect it and don’t chase the number down by dropping your power too far. If you train by power, a big drift is a sign to cool down, drink or end the ride.
How to ride zone 2 outdoors
Outdoors, zone 2 is harder to hold. Climbs push you up into Tempo, and descents drop you into Recovery.
- Pick flat or rolling routes for zone 2 days.
- Shift early on hills and accept going slowly up them.
- Ride alone or with patient friends. Group rides rarely stay easy.
- Look at your average and time in zone after the ride, not every second during it.
Outdoor rides still count toward your training. If you connect Strava, WattAscent counts outdoor rides and other activities toward your training load, using power or heart rate.
How much zone 2 should you do?
There’s no single right amount, but the research points one way: most of your training time should be easy. The elite athletes in Seiler’s review did about 80% of their sessions at low intensity (Seiler, 2010).
Count by sessions or time, not by how you feel at the end of the week. If you train four days a week, that might mean two or three easy rides and one or two hard ones.
If you have only a few hours a week, the balance shifts a little. WattAscent automatically picks a polarized plan at 6 hours a week or less, keeping your easy rides easy and your hard ones focused. Our time-crunched training guide goes deeper on limited-time weeks.
If you have any health concerns, check with your doctor before increasing your training volume or intensity.
Common zone 2 mistakes
- Riding in Tempo by accident. It’s the most common mistake: too hard to be easy, too easy to be a real workout.
- Ignoring heat indoors. Without a fan, a steady ride gets harder than it should be.
- Using the wrong FTP. If your FTP is set too high, your zone 2 is really Tempo. Read what FTP is to make sure yours is right.
- Skipping the hard days. Zone 2 builds a base. The trial evidence says it works best alongside some high-intensity work (Stöggl & Sperlich, 2014).
- Chasing a heart rate number on long rides. Drift is normal (Souissi et al., 2021).
Zone 2 with WattAscent
WattAscent builds your plan around the research above: plenty of Endurance riding, with harder sessions placed where you can recover from them. As your FTP changes, Adaptive FTP moves your Endurance zone with it, so your easy rides stay easy. If you want a plan that keeps you honest on easy days and focused on hard ones, start training.
Frequently asked questions
What is zone 2 in cycling power?
In Coggan’s seven-level system, and in WattAscent, zone 2 is the Endurance zone: 56–75% of your FTP (Coggan, 2016). Other systems, especially heart rate ones, may define it differently.
Is zone 2 training enough to get faster?
On its own, probably not for trained riders. In a 9-week trial, a polarized program that mixed easy riding with high-intensity work beat a mostly easy, high-volume program on key endurance measures (Stöggl & Sperlich, 2014).
Can I do zone 2 training indoors?
Yes. It’s often easier to hold zone 2 indoors than outside, because ERG mode keeps your power steady. Use a fan and keep your cadence natural.
Why does my heart rate rise during a steady zone 2 ride?
That’s cardiovascular drift. During prolonged exercise, stroke volume falls while heart rate rises (Souissi et al., 2021). It’s normal, so judge a long steady ride by your power, not by holding one heart rate.
How long should a zone 2 ride be?
There’s no fixed minimum. Longer rides add more easy volume, but shorter endurance rides still count, as long as your week also has some focused harder work.
References
- Coggan, A. (2016, updated 2026). Power Training Levels. TrainingPeaks. link
- Seiler, S. (2010). What is best practice for training intensity and duration distribution in endurance athletes? International Journal of Sports Physiology and Performance, 5(3), 276–291. link
- Stöggl, T., & Sperlich, B. (2014). Polarized training has greater impact on key endurance variables than threshold, high intensity, or high volume training. Frontiers in Physiology, 5, 33. link
- Stöggl, T. L., & Sperlich, B. (2015). The training intensity distribution among well-trained and elite endurance athletes. Frontiers in Physiology, 6, 295. link
- Polarized vs. threshold training intensity distribution on endurance sport performance: a systematic review and meta-analysis of randomized controlled trials (2019). Journal of Strength and Conditioning Research, 33(12), 3491–3500. link
- MacInnis, M. J., & Gibala, M. J. (2017). Physiological adaptations to interval training and the role of exercise intensity. The Journal of Physiology, 595(9), 2915–2930. link
- Souissi, A., Haddad, M., Dergaa, I., Ben Saad, H., & Chamari, K. (2021). A new perspective on cardiovascular drift during prolonged exercise. Life Sciences. link