I am fairly new at cycling and there is something that I don't understand about the training aspect of it. I have a long sports history (I was a professional swimmer for most of my life). Now that I got into cycling I keep reading that zone 2 training is the preferable method of training. I can sustain zone 4 training for 3 hours of a ride and I don't understand why to train in zone 2 when I can train in zone 4. Wouldn't it improve my endurance and vo2 max if I train with higher effort?
Hah, thought the exact same
Me too. How were you a pro swimmer?
Thank you for pointing that out, garmin was suggesting my zone was 158-177 bpm. I did Lthr test as many suggested and It came up to be 182 bpm. So my zone 4 is actually 171 to 180 acording to Joe Friel's guide.
That makes a lot more sense.
Very skeptical that a professional endurance athlete of any kind would not understand base training. This has been ubiquitous for almost 30 years.
Here it is folks - the most confidently incorrect person of the day on Reddit.
I guess we went down in flames 🤣.
Pro swimmers are built different.
Phelps has a pair of Lungs that can hold up to twice the amount of air as an average male
yeah and he spend 6 hours a day on training 99% was at z2
Or Z1.
Why not? I know my zones and racing put me around middle.of zone 4 for as long as its needes, sure 3 houra or.longer is a stretch but up to 3 hours, easy. Its treshold hr, by dwfinition is something you can hold for a while.
What happens is you will be glycogen depleted. It's going to happen after the 2 hour mark but I don't know exactly when.
It's possible. I did Zone 4, for 2 hours, so it's possible when you get to extreme fitness. But it's definitely over training. My body broke down from doing stuff like that.
Congratulations on your complete lack of understanding of power zones
Train in nothing but zone 4 for 12-15 hours a week and report back how you feel in 3 weeks.
There’s a reason why even top tier professional athletes don’t train this way. You’ll get your answer.
This! Really blows my mind on local cycling club: everyone just pushes "20min pulls, 5x5 intervalls, 1hr hard" every ride. Pogi trains like 80-90% on z2, why a average Joe some how can do max effort every day?
Well, I do 80/20 and smoke all of them in fast group rides. And no-one asks how I do it, just make fun of it: "you and your z2..."
😄 Can't understand the stupidity of people.
I read somewhere that it plays a big role in (professional) sports that the athlete can digest information and in a way coach themselves and/or understand why something is done and what sort of effect it has on results/recovery/body/etc.
You can't do zone 4 for 3 hours. Your zones are wrong.
It could be I dont have a power meter I am checking my zones from the garmin hearth rate sensor
It's almost certainly wrong. Either the sensor is wrong or you've calculated the zones incorrectly. Heart rate sensor chest straps are very reliable and are relatively cheap.
Agree. Power is the standard for zone training now. I only use heart rate to gauge (or really to confirm what I’m feeling) fatigue and see training progress (lower hr for the same power). 3 hours at the very bottom of zone 3 might be possible, but it would destroy anyone.
Power meter is great for zones 3, 4, & 5 because you're normally doing intervals in those zones. HR monitor is really best for zones 1 & 2, longer sustained efforts.
But a power meter is good for tempering those efforts. For example, I can ride in zone 3 for a significant amount of time before my heart rate creeps into zone 3. Many people will end up spending a lot of time in other zones if they pay attention only to HR.
What he's talking about is that because the point of riding in lower zones (particularly zone 2) is that it's a particular metabolic state you are targetting for adaptation, riding by heart rate is better for those efforts - with the caveat that of course there is lag so don't send it on hills, etc. But that fact doesn't mean you should be using power meter for those efforts, if you ride zone 2 power you will start out at zone 1 heart rate (fine) and end up if you carry on long enough in zone 3 heart rate or more (not fine at all for the purpose of zone 2 rides), which is not the point of zone 2 riding - which again, is to target a particular metabolic state. Higher efforts (intervals) should of course be done by power because that's what you're targetting with those things, repeatability of riding at a particular sustained power.
As an aside it's very much incorrect that riding very bottom of zone 3 for 3 hours "might be possible" or "would destroy anyone", Sunday I spent an hour and ten minutes in the upper end of zone 3 with an hour and a half in zone 4 - and my heart rate zones are dialled. My power zones are also set up correctly and confirm that I spent most time in zone 4 (apart from drafting effectively/freewheeling downhill, etc., in zone 1, which is always the case unless you're alone on a TT circuit). Average for the 3+ hour ride was 152bpm, 2bpm lower than my zone 4 lower boundary of 154bpm (I did have a cafe stop of half an hour or so filtered out). It was a Historic Relative Effort of over 400, but completely doable - though very much into overreaching territory and not advised to do on a regular basis at all. But it hasn't destroyed me or anything, I have 15 hours left on Garmin Recovery Time with "Train as Usual" advice and will go for a medium-hard short ride later today.
Sorry, I what I meant was 3 hours in zone 4 would destroy pretty much anyone. I agree zone 3 is very doable.
Ah yes, correct.
Garmin puts Z2 as 60-70% of max heart rate by default, which is super low for me. My max measured heart rate is 191bpm so Garmin says my zone 2 is 115-132bpm but I can sustain 150bpm for hours (current longest ride is 8h35m42s).
Then your zones are not what garmin says.
I'm aware lol
those are not the same kinda zones
If you haven't directly tested your max HR, preferably with a chest strap monitor, your zones are almost definitely wrong.
Warm up 15-20 min., do a couple of easy intervals to get your HR up, then after your rest period (still doing easy cycling, of course) mash the pedals for the hardest 90 second to 2 minute interval you can muster. Check peak HR. Use that as your max instead of the one your Garmin assumes based on age.
Ofc you can, you cant do zone 5, but 4 is almost easy.
Your zones are set up wrong. You can stretch low Z4 a bit past an hour, maybe 90 minutes, but by the end of that you really shouldn't be able to keep the pace up. Mid Z4 is supposed to be set up as the maximum effort that you can keep up for an hour.
Zones are not a fixed thing. Your zone 4 and my zone 4 are different, what others are pointing out is that, if you can be in zone 4 for 3 hours, then, for you, this is zone 3 because you shouldn't be able to maintain zone 4 for so long.
Yes. Zone 2 is filler. You don’t only train in that zone but place it around harder workouts to add volume with lower fatigue impact.
Thank you for your answer, that makes sense. In that case I should train with high intensity as long as I can recover from it and fill the rest with low intensity training.
Yes. “Zone 2” training is massively misunderstood.
It is part of a polarized training plan. Meaning you train at both ends of the spectrum with nothing in between. (Compared to Pyramidal training) The 80/20 thing: 20% super hard efforts above threshold And the rest 80% is easy. Zone 2 correlates to where your blood lactate is at 2mmol so it is the most efficient steady state for exercise. This way you can ride high volume without accumulating massive fatigue.
The Key is actually doing the 20%. You need to be doing all out V02 efforts. This is where fitness is gained and improvements are made. The zone 2 time is to build an aerobic base. It makes you more fatigue resistant, but it doesn’t necessarily make you faster.
Personally I think if you’re doing any less than 6-8 hours of riding per week, your better off doing sweet spot or pyramidal training. But if you’re up in the 10-20 hour range, doing a block of polarized training can really help you get long hours, volume and build that base.
From what the coaches say, it is a training style to use when it suits your needs. It is not an “end all be all, this is the best approach”.
If you want to and have the time to ride 12hrs a week, the only way you’ll be able to recover from your high intensity days, is by doing low intensity. Hence Zone 2.
Don’t let Huberman and Attia confuse you. Get a power meter, do a FTP test. Structure your training. And get fitter and faster.
Otherwise, ride hard AF 1-2 a week. And the rest of the time try to keep your HR in a well calculated zone 2. 👍
After many months of 80/20 I noticed that I recover very well from a) hard rides afterwards and b) during hard rides i.e. intervals etc.
And it is nice to ride fast af in group ride at z2 hr, when others are huffing and puffing 😄
training is a focused damage on your body with an intention to push it to rebuild stronger
so the amount of your training is very strictly connected with your recovery ability
unless you go for an olympic medal where some training regimes are strictly crazy and sustainable for couple of years max and result with a gold and over fatigued body, you ae ok with max two strong efforts during a week.
if you want to periodise your training on a monthly/yearly basis which can give you much better results once max twice a year, you want to rise intensity towards the race but first build volume with z2 (bc it gives you volume and mitochondria adaptation but generates less fatigue)
during the intensity phase you want to rise intensity and you can do it bc you are fresh (from your yearly plan perspective) so the intense workouts can be very intense but still twice a week max and all other rides are z2 just to keep weekly volume but not destroying the intensity of those two hard workouts. /reason why it can be even low z2 bc a bit easier ride is ok if the hard workout not day is 100% and not 98%.
in short it is really about the amount of hours a week
if you ride less then 8, you can do wahtever
10-15 you can still almost do whatever if you are young, if you are 30+ 2 hard workouts max and rest z2 is ok
15+ you want to periodize yearly bc you can easily just destroy your body or just over fatigue and get injured or lose the motivation etc. there is a reason why pro athletes are at best max for a couple of weeks during a season and they do off-season with no training at all
ps. another story is that different zones are impacting different things, so if you want to hold 1h at z4 (with correct zones) you must first get used to 4-5h at z2 just so your body have enough sustain
It’s not just lower fatigue impact. Studies show that periodized training mixing low intensity base with high-intensity intervals yield higher performance than going hard the same amount of time. Joe Friel’s Cyclist’s Training Bible is well, the Bible on this.
It’s been a long time since I was training seriously, but my coach, a former Olympian, claimed that the role of base was to build out cardiovascular infrastructure like capillary density, for which intensity is less effective.
I used to be like you. Push it as hard as I could for as long as I could stand it. That was always how I trained.
What I found is, especially as I aged, if you strain all the time, your body will break. And even before the breaking started happening more, my top end sprint type fitness was top shelf but my long term endurance sucked donkey balls. So I could play basketball for 4 hours (sprinting and leaping but downtime between sprints). But I couldn't jog for 30 minutes at any respectable pace.
These days, I train zone 2 mostly because it doesn't break my body. I recently rode with a friend who is a much stronger cyclist than me for 3 hours. He was in his Zone 2 ride, and I was at Zone 4 for lots of it even tucked in behind him. And guess what, next day: Minorly but still pulled calf. I kept up, but at what expense? Missing a few weeks of summer riding while I do a rehab. Not worth it.
Definitely feel your way on training but listen to the experts to give you good guidance to get to whatever your goals are.
How many 3hr+ rides are you doing each week?
Not so many I usually ride around 8 hours a week
8 hours is about the point where common advice becomes to add some zone 2. If you're doing 8 or less you have little to no reason to target zone 2.
There's significant additional ANS (autonomic nervous system) stress when you cross VT1/LT1. This is why almost every endurance training plan for the last several decades limits to 3 hard days per week, no matter the goals or fitness of the athlete. Zone 2 targets the area right below these first ventilatory and lactate thresholds in order to get additional effective work done while still being able to recover from the hard workouts that will trigger more significant adaptations.
Thank you, I would like to improve me cycling and trying to construct a training plan for myself having few hight intensity days and filling the rest with zone 2 seems like a good aproach.
Yep, that's the standard format that has stood the test of time. 2 days at either LT2/FTP, Vo2 max or sweet spot/tempo, and 1 day long. Everything else is Zone 2 or recovery. Easy days between hard days. Even the pro runners and triathletes I know follow this format (they just stack multiple long high intensity workouts on those 2 hard days, and sometimes even inside the long day)
There are *heaps* of resources available to you on youtube which go into great detail about how to construct a cycling training plan for all sorts of goals. One group that I've found very helpful has been Cam Nicholls and the Road Cycling Academy. They have a free ebook and regular newsletter.
I spent nearly a year really smashing myself, riding 26-27 days every month with three fast-paced (30kmh++) bunch rides of 40km/h. Then I had to stop because I got sore. Also my family wanted to see more of me. Since then I've moderated how I ride a lot.
Monday/Tuesday are actually running days (5km at around 6m15s/km) - my exercise physiologist recommended this for cross training.
Wednesday and Friday are 25 km intervals, 2x20km commutes (the goal is to arrive alive and not smashed), Thursday is 50km speed effort with minimal climbing. Saturday is an 80-100km effort often including an hour (total) of pushing 40km/h++ and Sunday is a cruisy social 65km effort averaging 23km/h.
This past Saturday I did a 108km ride, averaged 26.6km/h, 56 minutes in HR Z4. Strava rated it a '436' on their relative effort scale. On Sunday I did a recovery ride where I kept an eagle eye on my heart rate, mostly keeping it in the 110-135bpm range for a true HR Z2 effort. It was surprisingly difficult tbh - on some of the inclines coming home I had to really drop my speed to keep the HR down. Woke up Monday feeling amazing.
In summary: HR Z2 is for recovery and building endurance. The professionals do it (in all sports) and you should too.
Also, you are only looking at the "strain" side of the equation, not including the "recovery" side. The idea of high-volume / low-intensity training is that you derive a good amount of physiological benefit WHILE ALSO not triggering a lot of recovery need.
Said differently, you strain your body enough to make progress, but not so much that it impedes your next training session.
It sounds like you don’t know what your zones are, I suggest doing a lactate test
If you can ride in a zone 4 for 3 hours then that is not your zone 4. Sounds like your zones are calculated incorrectly.
I saw your using HR and not power. HR has too many variables on a day to day basis. Sleep, nutrition, hydration, stress, temperature, medications etc. Can all affect your HR. 200 watts is 200 watts everyday regardless of those factors. Yes power also has its flaws so a combo of using both is best.
Zone 2 is good cause it causes training adaptations with minimal stress so it's easy to recover from. Same reason why sweet spot intervals are so good.
Zone 4 for 3 hours is likely impossible. If you can do it for 3 hours it's not zone 4. Even zone 2 for 3 hours can be difficult, especially for a beginner
Edit: likely impossible for most non pros, especially novice riders, such as OP. I'm sure some pros get do long zone 4 sessions especially when racing
You ever raced?
That's not the definition of Zone 4. Some people can do Zone 5 for an hour if you mean maxHR. If you mean max 1 hour effort, it could put you at 90% of maxHR for some younger athletes.
It's not impossible. I did it for 2 hours. Zone 4, for 2 hours is possible and I have photos to show I did it. But I'll also admit it was one of the most stupid things I did. Overtraining was the result and it took years to recover from being stupid.
Ah, so you didn't do zone 4 for 3 hours then. I'm sure some pros and super fit people can get close to zone 4 for 3 hours when racing but for most mere mortals it is not feasible (or wise), especially if you are a novice, as the OP is. The wider point is that it is almost certain that OP was not in zone 4 for 3 hours
I said 2 hours. I never said 3 hours. And honestly I don't know why I was able to do it, but the heart rate monitor, calories burned, all of it says I was above 80% of my max heart rate and by that definition it was my zone 4.
From what I remember it was from being conditioned. I was in the habit of working out for 4 hours every day for over 6 months by then.I don't think OP did 3 hours of Zone 4, clearly, but I do think 1 to 2 hours of Zone 4 is achievable and I'm not the only one who has done it.
Maybe ask the OP to post their photos or documents showing they were in Zone 4? If it's from a chest strap heart rate monitor and they have a documented max heart rate, it's about as accurate as they can give you short of a lab study.
Just for additional clarification how are you defining Zone 4? Is it by 80% of maximum heart rate? Or is it by some other metric? When I said I spent 2 hours in Zone 4 and have the document, I mean above 80% of my maximum heart rate. If you're defining zone 4 as 90% of max heart rate or some other definition then I concede your point.
My records show it was over 80% max heart rate, with occasional peaks into 90%. Over 1500 calories were burned in 2 hours. Today I couldn't do something like this, as I struggle to do 1.5 hours of Zone 2, and I stick to lower intensity now.
The only way what I'm saying is wrong is if we disagree how how Zone 4 is defined.
Depends how much you're training. If you're doing 15 hours a week then you'll probably need a fair amount of it to be easier volume just in terms of recovery and stuff, though you should still be doing higher jntensitt work as well. If you're only training 5 hours a week you could probably make pretty much all of that higher intensities just fine.
But also just be aware that zones are only useful if you've properly set them. If you're using defaults or age based calculations then for all you know your "zone 4" could actually be zone 2.
Threshold is what you can do for an hour without failing. If you can put out a wattage for 4 hours, its not zone 4.
So, for you, as an experienced athlete, it is probably better to think of “zone 2” as elevated, aerobic, endurance pace or between Lactate Threshold 1 and Lactate Threshold 2 (LT 1 and LT 2).
The point of training in this aerobic zone (between LT1 and LT2 is literally building Type 1 endurance muscle and the vascular capillaries that feed and remove waste from these muscle cells.
In a 7 zone system for someone training long hours this usually means the top of zone 2 and the bottom of zone 3 so long as you are in aerobic activity avoiding pushing into LT2 and rapid rise of lactate levels. But there are biological reasons to add time at lower zone 2 (warmup) to this composite of time in different zones.
So what’s going on biologically in “zone 2” or just long distance aerobic training:
Early on during warm and entering zone 2 your muscles (particularly your type 2 muscle cells, are expressing a lot of mitochondria witch aid the ADP-ATP energy cycle of breaking down glycogen (stored in your cells) and glucose (supplied by blood flow). Your body is also expressing cortisol and it predecessors. Your cells are “inhaling” more water and oxygen and nutrients than normal expanding their volume and surface area and exhaling waste products (like CO2).
All of those processes actually aid the building of new cells, repair of old cells, and building new capillaries later after you return to a resting state and get a good nights sleep. Specially, higher levels of mitochondria, cortisol, and micronutrients delivered are critical to those things.
Cycling is an endurance sport. Aerobic energy production—watts produced for energy consumed—is significantly more efficient than anaerobic energy production. Anaerobic energy production in Type 2–high twitch muscle burns more energy for each watt produced.
Unless you are going to dive into track racing or lots of hill climbing events, where rapid acceleration and power are critical, your main goal is maintaining speed over distance for long periods of time.
The more Type 1 muscle you have, then, the faster you go in the long run—especially that 3rd, 4th…8th hour in the saddle because on the long haul what limits you is energy efficiency.
So the point of aerobic training is building the right muscle for endurance.
That does not mean don’t do high intensity workouts in the anaerobic zone. You should. Especially if you are thinking of racing or long touring with elevation where steep grade climbs are going to force you into higher zones anyway. Also, high intensity high zone work will aid VO2 max development which will also benefit endurance capacity.
But if your goal is the ability to take on long 3-6 hour rides and feel good doing it the more endurance aerobic training you do the better.
Final note: Younger athletes have a bad tendency to discount warm downs. But good warm downs are super critical for maximizing Type 1 muscle development.
The evidence points to polarized 80/20 rule as being the most effective training. So if you want to do Z4 for 3 hours, that needs to be balanced by 12 hours of Z2.
Roses are red.
Violets are blue.
I'd rather buy an eBike than ride Zone 2.
it's worth to mention- are you talking about power and coggan 7 zones, or something else. or you are talking about heart rate and friel 7 zones, or perhaps it's heart rate and coggan 5 zone model? because it makes a lot difference what you mean by zone 4.
not sure where you read that, but zone 2 is definately not preferable method. preferable method is polarized training where a lot of work is done in zone2 but as important is high intensity work above threshold, but this also shifts depending on in which training phase you are in (base, taper, peak).
zone 4 (coggan power model) in this regard is complete junk miles, you don't train either endurance nor vo2 max there. the only time you would spent in zone 4 is by doing time trial race. period.
regarding endurance and vo2 max, endurance is trained on long zone 2 rides. your body makes adoptations it won't make in any other zone and rides have to be long enough, 30 minute zone 2 ride is waste of time. vo2 max is trained above threshold, zone5 or higher (again coggan power model) hence the high intensity work.
hr zones are different from power zones
Because variety is the spice of life and in sport. If you were to train at z4 all the time, your body would adapt and you’d hit a plateau (not to mention increase risk of injury). By adding variety, not only is it more efficient but you will see larger gains.
To say nothing of you’re working different systems. Z2 is about building cardiovascular endurance (ie your motor) while higher efforts are about building speed.
Sounds like your Zone 4 is actually Zone 2.
It’s not just that you can’t train harder. It’s that periodized training is scientifically proven to make you faster than just going hard all the time.
Joe Friel helped popularize periodized training with lots of Z2 and it made people a lot faster. He specifically said that his athletes did better when they did their base lower in zone 2 versus at the top.
Overtraining is also very real in elite athletes.
Zone 4 power should only be possible for an hour max? I'm assuming you're talking heart rate. If not you need a new FTP test.
thats not how zones or ftp work
Youe treshold hr should be somewhere down the middle of zone 4, so you literaly can do zone 4 for a few hours.
Physiologically speaking, zone 2 training stimulates the synthesis of more mitochondria. This literally lets your body produce energy more efficiently. Think of it as tweaking a car engine to be more economical with its fuel.
This will then enhance your higher zone efforts. Not achievable by only training in higher zones.
So do zones 1 to 6.
Heck, zone 7 sprints will stimulate mitochondrial biogenesis if you keep the recovery periods short enough.
How many hours per week are you riding? I think zone two training plays an increasingly important role when you’re approaching professional levels of time in the saddle. And when your high intensity work is of the shockingly high output pros are capable of. At some point doing three hour zone 4 rides will make it very difficult to do the zone 5 and above work that is so very critical.
It takes 6 months of Zone 2 to build an aerobic base. After you do this, you can decide if you want to build an anaerobic base on top. When I was in my most fit ever I was able to do Zone 4 for approximately 2 hours. I learned soon after, that I was over training. It took me 2 years to recover physiologically, and some aspects took 4 years to recover from. Don't over train, it's not worth it.
Build a strong Zone 2 base, spend 6 months on that, and then you'll be in a better position to add some Zone 4, maybe 20-30 minutes a week, maybe an hour a week at the most. If you want some Zone 5, then 14-20 minutes a week at most.
You did not ride in “zone 4” for 2 consecutive hours. I’m not sure why you felt the need to parrot that in every comment on this thread but it is empirically wrong to even suggest that that is physiologically possible by all currently held definitions of threshold. Sweet spot (90% FTP), maybe with enough progression, but extremely disingenuous to call that proper zone 4.
If you don’t understand how zones work then stop spreading bullshit that isn’t true.
I have the photos to prove it. Just because you can't do it, it doesn't mean other people haven't done it.
Photos of what – your incorrectly set zones?
Do you truly not see the forest for the trees?
I keep records of my PRs. My zones were calibrated by a test. My maxHR was known. The Zone 4 at the time was accurate. You can train in 2 hours at Zone 4. I am not saying it's good, or that the outcome for me was good, but it is physioogically possible.
Zone 4 is just under the threshold where you burn entirely lactate. You also burn fat if your fitness is very high which can extend how long you can do it. So yes it is possible to spend 2 hours in Zone 4. At the same time it is overtraining to do it, as the body burns muscle when it runs out of fat.
It also wrecks your stress hormone levels, lowers your testosterone levels, makes you at risk to injuries. I know all this because that was the consequence in the months following. You can take what I say and believe it or you can think my Zones weren't correctly calibrated, it's up to you.
Here is another person who spent 2 hours in Zone 4. Maybe show a study proving no one can spend 2 hours in Zone 4 to change our minds.
https://www.reddit.com/r/Garmin/comments/15y5svp/heart_rate_zones_2_hours_of_z4/
What you’re describing is literally just sweet spot. You did sweet spot for 2 hours. Marathon MTBers can do sweet spot for 2 hours. Gravel racers can do sweet spot for 2 hours. But nobody - and hear me out - nobody can do 100% FTP for 2 consecutive hours. It is literally in violation of the physiological math.
Zone 4 is just under the threshold where you burn entirely lactate
My guy - you don’t know what lactate threshold is. This is embarrassing for you.
If you use the chest strap with power meter while riding, does that calculate your lactate threshold th3 way it does when you run?
The bottom line is it develops you at the cellular level. You add more mitochondria and more powerful ones at that training in z2. As has been said your calculation for z4 is off a bit I suspect. Probably you’re riding z3. Which you can sustain for a while. Z4 is Upper LT to low VO2max. The most important thing to know about any zone training is you cannot use formulas if you do you could be a whole zone off most likely a half zone.
You ain't doing zone 4 for 3 hours. Zone 3, sure. But do your research and you'll understand that if you have the time to train adequately, riding in zone 3 for hours isn't the ideal use of your time.
If you have the time, long slow and short all out is closer to ideal.
Also recalculate your heart rate zones.
Zone 4 training is great. You need adequate recovery, though, and Zone 2 rides offer you the ability to recover from strenuous zone 4 workouts while still enjoying the benefits of aerobic training.
Not every workout can be full gas. If you spend most of your time in zone 2, then you can do zone 4 and 5 training once or twice a week while maintaining a high aerobic training load the full week long and still being able to recover.
Plus, at a certain point, even zone 2 training gets to be difficult. Pros are doing 100-mile zone 2 rides at 250+ watts, and that’s a huge training load even though it’s ostensibly at a “conversational pace.” Keep training to increase your FTP, and you’ll soon see that zone 2 training is no picnic.
In fact, behind zone 2 is the normal healthy development of your heart muscles - you cannot be in good shape if you train your heart to be sick.
The right training in the right ratio brings the result - there is no quality training and non-quality training. Elite cyclists ride the first hours of the Tour zone 1-zone 2-now think why should they train with a higher heart rate at all?
GCN has several videos on the matter. Go watch them and you'll understand perfectly "everything" you want to know about it.
This zone2 stuff is in the context of riding multi-stage events and 4-6 hour races where most of your power will be in zone2 simply because you're drafting in a pack or trying to conserve energy.
There's 2 types of zone2: The recovery and the endurance.
You'll see lots of workouts that add lots of zone1-2 between intervals and it's main purpose is to let you recover or to warm up. So you aren't getting any adaptations from zone2 here.
For endurance you're getting adaptations because you're sitting on the bike 5-6+ hours. So it's not about total volume of zone2 in your week, it's about doing it all in one go. If you sprinkled in a bunch of random 30 minute zone2 rides it wouldn't do anything.
Given that, I have no idea if you could do a super long tempo ride to replace an even longer zone2 ride.
Like is a 3 hour tempo ride the same thing as a 5 hour zone2 ride?
It doesn't really matter overall anyways. What exactly are you trying to accomplish as someone new to cycling? Are you going to work towards being an elite cyclist in an important competition? There is no wrong answer here, and there is no wrong way to do something as long as you are enjoying the process.
No you can't. You're calculating your zones wrong.