The strongest rider on your local group ride might have an FTP of 350 watts. If you’re in the company of cycling’s elite, maybe there is a rider with a 380w or even 400w FTP, or functional threshold power – meaning the highest average power that rider can produce for an hour. A true FTP test is a lung-bursting effort, an all-out, one-hour time trial.
FTP is seen as the absolute limit, the hardest that you can go for a sustained period of time. Zone 2 is something completely different – it is your aerobic threshold, the highest average power that you can produce without accumulating a significant amount of lactate. In other words, your body can clear lactate as quickly as it’s producing it when you’re riding in zone 2.
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If you are the team leader and the out-and-out race winner, you want as much explosive power as possible so that you can attack and drop your rivals. On the other hand, a domestique doesn’t typically care how much power they can produce for three to five minutes. Instead, they need to be able to ride on the front of the peloton all day – sometimes every day, for three weeks straight in a Grand Tour.
How do the pros define zone 2?
Zone 2 has nearly as many definitions as FTP. It may change depending on who you ask, but it is typically defined as the steady state aerobic threshold, the point at which blood lactate begins to accumulate significantly. In basic terms, zones 1 and 2 are talking pace, before your breathing becomes labored and the sweat starts flowing.
A proper zone 2 ride is done at between 60-75% FTP by power-based training. However, you’ve probably noticed that the range is massive. For a rider with a 400W FTP (remember, we are talking about pros here), that is a range of 240-300W. So when this rider goes out for a zone 2 ride, what power do they target?
After researching multiple professional riders and coaches, we’ve seen that riders actually use this full range in their zone 2 training. Instead of targeting a specific power output, they vary their target power based on terrain, altitude, weather, and other factors.
How the pros train their zone 2
Using a range of 60-75% FTP, pros tend to alter their power target based on the length and difficulty of the zone 2 interval. The longer and easier the interval, the higher the target power within zone 2. So let’s take a look back at our example pro with an FTP of 400W.
This rider can target anywhere between 240W and 300W during a zone 2 ride. However, if they live in Andorra, they will be riding up and down climbs all day, and it would actually be impossible for them to do four hours of uninterrupted zone 2.
In this case, the pro would likely target high zone 2 (70-75% FTP) on the climbs, and then recover on the descents. Realistically, it would be impossible for them to ride at 240-300W down the descents anyway.
Tadej Pogačar himself discussed his actual zone 2 numbers on the Peter Attia podcast, saying that he rides at 320-340W during his zone 2 rides. However, this only applies to his hilly zone 2 rides – he will target 320-340w on the climbs before recovering on the descents. Pogačar lives in Monaco, so most of his training rides are extremely hilly.
But when Pogačar goes to training camps and rides flatter roads, he actually alters his zone 2 training to match the terrain. If he rode 320-340W for five hours, he would be so fatigued that he said, “the next day, I would not be riding the bike.”
When riding on the flats, Pogačar drops his zone 2 power all the way down to 290-300W. We’re talking about a 50W drop in zone 2 power at most; that is a massive difference. But for Pogačar, there is nowhere to recover on the flats, so zone 2 rides are much harder.
“Your zone 2 after a five-hour ride, it might not be your zone 2 anymore,” said Pogačar.
Pogačar weighs roughly 65kg, so a zone 2 ride at 320-340W is 4.9-5.2W/kg. But there are plenty of heavier riders in professional cycling who have raw power outputs that dwarf Pogačar’s. Riders like Filippo Ganna, Wout van Aert, and Nils Politt weigh around 80kg, so you can expect their zone 2 rides to be done at 350W or more.
Sport Engineering Director at Team Jayco AlUla, Marco Pinotti, said: “We have always prescribed ‘sustained power output for a long time’ or shorter intervals at slightly higher intensity.” When it comes to steady zone 2 rides, Pinotti said: “We look at the trend of the Power/HR [heart rate] curve and Power/HR value.”
Heart rate drift and the Power/HR curve are crucial data points used by professional coaches. The fitter the rider, the more stable their heart rate will be during a long zone 2 effort. Amateurs may see a significant amount of HR drift during long rides, where the HR increases over time due to aerobic fatigue.
Coaches like Pinotti often use Lactate Threshold 1 (LT1) when prescribing zone 2 training. LT1 is the point at which blood lactate starts to accumulate above resting levels. Basically, it is the upper limit of aerobic riding, or the line between zones 2 and 3. While zone 2 is a broad range, LT1 is a specific intensity or power output that can be determined through lactate testing.
You can see two different zone 2 rides in the images from TrainingPeaks below. One is for a rider completing zone 2 intervals, somewhere around 140-150bpm, with recoveries in between each effort.
Pinotti said: “In this instance, I prescribed a bit higher PO intervals at LT1 (4W/Kg) to the rider…It depends on the place they train, if they have mostly climbs or descents, we look to prescribe more intervals at LT1 rather than continuous effort, which is impossible to do.”
The second zone 2 ride is a steady one – you can follow the rider’s power and heart rate in a nearly horizontal line across the chart.
Zone 2 power can also be adjusted for other factors, such as altitude or weather. Basically, anything that significantly affects your level of fatigue can play a major role in zone 2 training. The harder the efforts, the lower your zone 2 target power.
When our example pro goes to an altitude camp, their 240-300W zone 2 might become 220-280W. Riding at 300W would quickly push them into their tempo (zone 3) and cause a significant amount of lactate accumulation. The same goes for hot weather. If a rider’s heart rate is already elevated from extreme heat, riding at the top end of their zone 2 could easily cause damage instead of positive adaptations.
So far, we’ve mentioned a number of factors that affect zone 2 training, but we haven’t mentioned one of the biggest factors of all: time.
Should you be doing zone 2 intervals?
Old school zone 2 training meant going out and riding all day. Sometimes that meant seven to eight hours, especially for the pros. They would ride at an easy tempo; perhaps they had a heart rate monitor, but they would never truly push the pace.
Modern zone 2 has evolved with the use of lactate meters, breathing sensors, power meters, and more. There are a hundred different physiological metrics you can track, but what does that actually mean? For a long time, it seemed like the best way to improve your zone 2 power was to accumulate more hours on the bike. Pros would do 30, 35, or 40-hour weeks in search of aerobic fitness gains.
But at a certain point, you cannot accumulate any more hours. In fact, many pros have stepped away from 35-hour weeks, opting for 20-25-hour weeks instead. It seems that quality has begun to outweigh quantity.
In search of zone 2 gains, some pros started doing zone 2 intervals. Similar to what Pogačar described in Monaco, pros started doing 10×10 minutes in zone 2 instead of 60 minutes straight. You can find several rides on Strava like this, such as this “6x20min LT1” from Tour de France stage winner, Jonas Abrahamsen. The Norwegian does this type of workout every single week, along with most of his Uno-X Mobility teammates.
The thinking is that you can accumulate more time at a higher zone 2 power output when you break the ride into intervals with short recoveries. It’s the same reason that pros do 40/20-second intervals instead of five-minute VO2 Max intervals all the time.
Instead of doing 4x5min at 450w, they can do 4x5x40/20s with target powers of 500W and 200W. By the end of the 40/20s session, they’ve accumulated more time at a higher power (500W vs 450W) compared to the five-minute interval workout.
“It’s common in Scandinavia at the moment to do 10min LT1 efforts instead of steady Z2 to become able to ride very efficiently/economically on a higher power output than before,” said Magnus Kulset, former teammate of Abrahamsen at Uno-X Mobility.
“From my personal experience, I think it’s a useful way to train. As LT1 is very controllable, you open on a power you know is under your LT1, and then you can be careful not to go over LT1, so you get a quality session in a controlled way. You do the power according to your lactate measurement, not based on heart rate or feeling. Where a steady zone 2 ride with similar/same average power in total will be more impacted by other factors, such as bad legs or high heart rate.”
What is the best approach to zone 2 training?
We’ve heard from Tadej Pogačar, Jonas Abrahamsen, and an entire professional team that zone 2 interval training works. So why isn’t every pro doing it? To be honest, I’m not completely sure.
Zone 2 interval training is certainly effective, but it may be more fatiguing for some riders than others. Pogačar and Abrahamsen are two of the strongest riders in professional cycling, so it isn’t a surprise that they can do zone 2 rides which consist of 6x20min at 330W – this is all done while keeping their lactate and heart rate in zone 2.
Does this approach work for amateur cyclists? Maybe, but it depends on a number of factors. First of all, what are you training for? It’s unlikely to be a three-week stage race like Pogačar or Abrahamsen. Instead, it is probably a one-day race that relies more on explosiveness than aerobic fitness.
Of course, having a 300W zone 2 is great, but you probably won’t win your local crit if you can’t accelerate far above that threshold. Many pros train to ride hard all day, every day. Some of them are breakaway riders like Abrahamsen. After an explosive effort to form the breakaway, riders like Abrahamsen will ride at 300-350W for multiple hours to maintain their gap over the peloton.
The ability to push this power is one thing. But for this power to be well within your zone 2 is a game-changer.
Why zone 2 matters, and how it helps win races
You probably won’t win a bike race by riding in zone 2 for an hour. But having a higher zone 2 can indirectly help you win – here’s how.
When you’re riding in zone 2 (or below), your body is clearing lactate as quickly as it’s producing it. Thus, you aren’t accumulating a significant amount of fatigue. In fact, riding in zone 2 (60-75% FTP) after a hard effort actually helps you recover because it helps clear lactate, arguably more so than simply coasting.
When you can recover in your zone 2 during a race, it gives you an advantage over all the riders who are pushing zone 3 or zone 4 power. While they are simultaneously accumulating lactate and fatigue, you are clearing it. By the time you get to the next climb, those riders will all be carrying fatigue, whereas you will be completely recovered.
This is one of the most underrated aspects of Tadej Pogačar’s arsenal. Everyone likes to focus on his raw power output, pure W/kg, ridiculous VAM, and unreal speed. But what truly sets Pogačar apart from the rest of the professional peloton is his fatigue resistance. And where does fatigue resistance come from? His zone 2 power.
At 320-340W, Pogačar is riding at 4.9-5.2W/kg. When his rival teams are ‘pushing the pace’ on warm-up climbs, Pogačar is riding in zones 2-3 while his rivals are in zone 4. This means they are accumulating much more fatigue than the two-time road world champion.
In a fresh 20-minute effort, there are probably 10-20 pros who can come close to Pogačar’s power and W/kg. But after 4,500kJs on the 18th stage of the Tour de France…that’s where Pogačar sets himself apart.
The magic of zone 2 shows itself in multiple ways. Some riders can pull on the front of the peloton for hours at a time. 350W is hardly scratching the surface of Nils Politt’s tempo zone. The large German can sit on the front at 45kph for over 100 kilometres, all while staying in zone 2.
Zone 2 also shows itself in fatigue resistance. The higher your zone 2, the more you can recover in between efforts, especially during a race when the pace stays high in between climbs and attacks.
Everyone can benefit from zone 2 training. Not only amateur and professional cyclists, but also the average human being. Zone 2 training is good for your overall health and fitness. It isn’t too difficult either, which is great news for those of us who are weighed down by the mental burden of a working life. You can hop on the bike, ride at a comfortable heart rate, and make significant fitness gains in just a few hours of training per week.
We can gawk at the pros as much as we’d like. But their 35-hour weeks in Mallorca don’t tell us much about our own training and fitness. Zone 2 is a term that’s been beaten to death since its inception, but for good reason. It is one of the most important terms and tools in physiological fitness, and it applies to everyone. Whether you are a beginner cyclist or Tadej Pogačar, you can make serious gains from zone 2 training.