Because the energy demand of riding 25hrs a week at 70% ftp for WVA would be huge.
70% is probably 300w + for him so that’s over 1000kcal/hr of energy needed and a lot of carbs.
EDIT: this is the explanation From Sebastián Weber which answered that exact question.
You can access some free webinars on INSCYD website about this. I think it’s called why Not to base your training zones on FTP.
Got it, thanks a lot for the clarification. So if I understood correctly for a pro riding at fat max continuously would be more about not being able to refuel such energetic requirements?
The topic starts to make sense to me with your input, because if Van Aert’s ftp is lets say 450 watts, 350 watts is only 77.7% and therefore is more or less top end z2.
Found the webinar @Kipstrong is mentioning: Why you should – or shouldn't base training intensities on anaerobic threshold / FTP — INSCYD
Yes I think so. It’s just such a high demand.
He said that a 6 hour “zone 2” would be at 300w + av following a typical Coggan zone system. This is like a Paris Roubaix average power and not really doable daily.
Another attempt to answer this question:
https://www.fastlabs.com/fasttalk109/
It’s trickier than you might first imagine. Not sure there is consensus about this. (also, you have to put with Trevor’s self-aggrandizement and San Millan’s poor connection).
The higher FatMax becomes (maybe moving into Coggan Tempo Zone 3 as mine has), the less of this training you can do as an overall % of your total volume because now it’s more muscularly demanding. If it’s still in mid Zone 2 (Coggan), you can dilly-dally around at that all day (almost literally).
Training at the bottom of the range is often missed by amateur and time crunched cyclist. One of the comments mentioned people’s reasoning for always having a high IF is because they don’t have the time for the longer slower training. You will reap the benefits of training at the lower IF even if it is only for an hour. Much, and I mean much, of my training is at an IF of 60-65%. At this IF, I’m completely aerobic and training the aerobic system. Also, at this IF I breath only through my nose which helps to train the diaphragm and the respiratory system. And, it engages fat as a fuel vice glycogen. As we know, humans are metabolically flexible and the longer we can maintain the glycogen stores, the better we will do in the long run. And, if you do the LST in a fasted state then you can increase your insulin sensitivity which will be a huge benefit when you do intake some CHO on a ride.
Much of what I hear on TR is about raising your FTP with the argument that a higher FTP will lead to a higher aerobic level. This is not the greatest argument because the aerobic and anaerobic sytems are different energy systems. The other way to raise the aerobic threshold is to train it by riding way below anaerobic threshold and building mitochondrial density. Yes, it takes time which is why most people shy away from this method. Dr. Phil Maffetone is the reference for low IF fat focused training. Also, there is a great link to they way in which Arthur Lydiard trained his athletes. Yes, Lydiard’s athletes were runners, but there is a strong correlation to Lydiard and Maffetone. Both suggest erring on the side of volume at a low IF and “sprinkling” in the high IF training as competition approaches.
This thread is quite in depth with the curves and the discussion on fat oxidation CHO crossover. This is great because science is important. But, much of training is intuitive which seems to get crushed by too much importance placed on structure. How many comments have you seen on people failing a TR workout? If you fail a workout, then simply spin easy for an hour or so and call it good while waiting for the recovery to take place.
As I’ve mentioned, great discussion. I will close with this thought, I have had phenomenal results from training at 60-65% IF while focusing on fat as a fuel. My training is probably 98% at this level and 2% with short intervals and the occasional hammer sessions with a friend of mine. After 10 months of focusing mainly on the aerobic system, I was able to ride 396 miles in 24 hours and 33 minutes. Two days after the 396 miles, I was 83% recovered according to my Whoop data. Today’s ride, 9 days after the race, was a hammer session and I was ripping the pedals off of the bike. So for me, low IF fat focused aerobic training works. It does feel like complete garbage when I first take the lid off and work on mitochondrial efficiency, but such is to be expected. At any rate, my thoughts on training at the low end of the spectrum and the benefits. In the end, Be Well and Ride On!
I’m not alone in having seen good gains using TR’s Traditional Base. The podcast crew favors sweet spot plans for various reasons, my own interest is building enough aerobic fitness (fat oxidation) to support long 5-14 hour adventure rides. While I don’t spend the money on gas exchange testing to measure improvements in fat oxidation, I’ve definitely noticed the improvements and other unexpected and welcome benefits like increases in 2-5 minute power.
These types of rides are long, whether done in TR’s Traditional Base plan or not. It was mentally and physically (my butt) challenging doing them inside on a trainer. Really killed motivation a bit to be honest. Outside is so much easier. Outside for the win-win.
This is probably right up there with the best thread I’ve been a part of on TR. The good thing is, because of the time difference being from Australia, I get to wake up and read all the responses after my post over breakfast!
Love the science discourse going on in here. Fascinating to hear the positive challenges and arguments that people are respectfully putting forward for each other. Great work guys!
I was thinking the same thing @Captain_Doughnutman. As @Berggeiss mentions, you’d have to have a fair idea of your power numbers at those ranges and perhaps have had lab testing done to quantify and triangulate those data points so that you know what range you are in. For us mere mortals though, we don’t have access to that sort of support.
That said, I might have to start training my wife to become my lab assistant … most likely in exchange for ticking some of the tasks off on the seemingly endless list of house modifications she has.
This is fantastic by you @SpareCycles! Thank you for sharing this. My take away from this is that we have much more flexibility and/or room to grow in the area of developing mitochondrial density through biogensis at the Endurance levels. Simply replicating a pro type training model may not be the best case scenario for everyone as the pro’s lower aerobic threshold is more developed than ours as indicated by the graphs you share. One of the reasons why I think it is important to take little golden nuggets away from pro training, but not try to replicate their training in its entirety.
I think this is where base training comes into play and the important of ‘trusting the process’ and not doing too much all at once. There is so much to be said about building your engine and engaging in a solid Endurance phase before you launch into more build and/targeted training phases.
Tim Cusik in his presentation talks about the importance of lifting the Power curve up, but also lengthening it (see below), which, true to the graphs you have shared, would lift the power output at a given blood lactate concentration. You also raise a good point about the ease of going over that tipping point where we start to see more of a contribution of carbohydrate to fuel the effort, and thus, more mitochondrial stress leading to blood lactate build up.
It really does highlight the importance of building your aerobic engine and stretching that curve out over time - ‘time’ being the notion that we all sometimes have trouble with in relation to wanting to see results. Also highlights the importance of keep your easy sessions easy and your hard sessions hard.
Build them so that they may grow. Mitochondria that is. And, grow in efficiency.
Good point @tshortt. Threshold is a lot easier to measure given the physiological limitations that occur at the point of FTP testing. The Aerobic Threshold is a lot harder to measure and perhaps you are right - given that there is such a focus on FTP in the discourse of cycling, as well as many riders focusing on 60-90 minute crits, LT1 doesn’t get treated with the same royalty as LT2.
This podcast is actually next on my list! About to go for a walk and have a listen. Very much excited to hear what is said.
Lets say you knew all 3, and they were at similar but different powers. I’m still a little confused how you would propose using that information? Can’t say I’ve drawn any conclusions yet from listening to San Millan on various podcasts. However I often listen to podcasts during the day, and tune out when super focused on something at work.
San Millan would have you train at or slightly above this intensity.
272.9 ± 20W at 1.3 mmol/L
Then look at Pogacar training very close to 275W
@sryke Also posted another UAE rider riding at similar intensity.
Seems like he just gives a target wattage.
@bbarrera But I think to your point (and I hope we don’t go down too much of a rabbit hole), these terms are slightly different concepts that we are bundling together to simplify the discussion. In my mind, there is some sort of “lower end measurement”. So measure it, do some training, and see if the number moves. I got on this whole kick because that number can move independently of a change in FTP. If you move it a lot, you can improve over durations that I’m interested in.
Yes it has something to do with fat/carb utilization, fiber type recruitment, training mitochondria etc. Yes, lots of riders understand these concepts (even if just basic level). So why do we not see many training prescriptions right at the border of Zone 2/Zone 3 (Coggan). When we do, it’s in half and full triathlon plans and hand waving about “race pace”. In fact, I’ve heard Tim Cusick say he avoids upper Zone 2. Edit: not anymore. And I would certainly not do much of it when doing threshold training (SST, Tempo, THR, etc).
I was thinking along the same lines. Thanks.
A general question regarding mitochondrial biogenesis.
Presumably, there’s a limit to how many mitochondria can be supported? For example, an athlete having done years of fasted training and being fat adapted, simply doing more fasted training/Z2 wouldn’t continue to pack in more mitochondria…? Would there then be an advantage of shifting to fueling rides to increase performance?
I ended up listening to this and it makes sense now e.g. Van Aert could not possible do a Zone 2 75% ride for 5 hours as the energy demands of this are humungous. It is like fueling a jet engine for five hours - intense amounts of fuel would be needed. On the flipside, someone with an FTP of say 250w could do a 75% Zone 2 ride because that would mean riding at 188w. In both cases the metabolic demands are the same however, the main difference is the limitations of human capabilities in relation to fueling.
The question I have is, in the absence of lab testing, how on earth does the average TR user know where their AeT is?! And as such, their FatMax zones and if they have drifted upwards into Tempo territory? This is the million dollar question.
Also, is there an inflection wattage point whereby Zone 2 rides become too taxing physically? Which would mean riding at 50% in perhaps Zone 1 and then doing 20min FatMax bursts like Van Aert does in his training?
you won’t be able to know for sure unless you do a lactate test in a lab. however LT1 and LT2 are highly correlated. So if you plug an accurate FTP into a basic 6 zone calculator like this: Power Calculator
then I would just take the cross over between Z2/3 as your LT1.
If you lack a lot of easy riding history (“aerobic base”) I would go on the conservative side. Likewise it can be higher than predicted if you are a rider with a lot of miles in the legs. But for both I don’t think it will be that far away
I’ve wondered this too @tshortt and have investigated it a little more in terms of recovery. It seems that the below table you shared shows that SM would have the UAE riders training at the border of Z2/Z3 in order to reach the 1.3mmol-L level? So for a 400w FTP athlete riding at 272w that would be around 68% FTP (Endurance Zone - 55-75% FTP)
I have been going down a very big rabbit hole and I am not even sure I have come out alive. I am in the learning pit. Deep, deep in the pit and I just can’t seem to figure out if what I am digesting is what all the information is saying. So, I will post some comments below and hope that more knowledgeable TR users may correct me or agree with me on some of the points I raise.
I was just listening to this podcast about the metabolic cost of cycling at different intensities and provided a great discussion for what we are talking about in here.
For us everyday Joe’s, riding at 272w may be VO2 max for some people. It may be Threshold. It might be bang on FTP etc. etc. Thus, depending on your current ability level, the mix of carb and fat usage when riding at 272w is comparably, and obviously, different depending upon your FTP. I think we all understand that one.
However, for a 200w FTP athlete riding at 68% FTP in their Zone 2 the output would be 136w. In both cases, and given the state of training of both individuals, the metabolic cost is the same, however, the fueling of the effort is quite different to that of a pro. Like a jet engine versus a 1989 Ford with a four cylinder motor.
From what I can gather, and from listening to Tim Cusick and his views, the stress of constantly riding above LT1/AeT leads to a build up of Reactive Oxidative Species (ROS) in the muscles. A certain amount of ROS is needed for physical adaptation however, if the cumulative build up is too great, and our natural antioxidant reactions do not have the opportunity to clear the ROS sufficiently, then the negative side of that build up tips the scales towards negative homeostatic interruptions e.g. compromised immunity etc.
Therefore, another difference may lie in the fact that pro’s have a naturally higher antioxidant capability than us, and as such, can train at a higher % of AeT more often because of their adaptive ability to clear ROS build up. Thus, they don’t get as fatigued at the higher %'s where as for us, we can still get the same physical adaptations by training in Z2, but it may be best to err on the side of caution and train at a lower % in order to monitor performance, adaptation and fatigue levels.
This is especially important considering that, more often than not, these Z2 rides are often accompanied by Sweet Spot, Threshold or VO2 sessions as part of a weekly training plan at the time. Thus, adding more load to the riders schedule.
So, I guess in summary, as an amateur rider, when you couple the Z2 ride with other sessions you are doing - whether that be in base, build or specialty - it is best to keep your Z2 ride at the lower end of the Z2 target so that you don’t over-reach and over-train.
This is supported by this article, Tempo - The Silent Killer, whereby the author speaks about riding at Tempo and getting sick as well as feeling ‘crushed’.
“Keep your easy rides easy and your hard rides hard.” - A quote that I keep hearing around the traps regularly.
Cue the critique please! Some great learning going on in this one.
The latest cyclingtips podcast is a really good listen, the last third is an interview with ISM. Initially the same stories but it turned into an really interesting conversation. There is a second part in the next episode next week.
W/r to his training model some notworthy remarks:
Adding the following (sort of dated) presentation from him, a more holistic view is possible now:
Looking forward to implement this after my last race. Ordered a lactate analyzer yesterday, always wanted to have one. This should make the next few dark winter months more interesting. I want to see how and if at all this curve moves. I start with his recommendation for 3-4days @AeT/LT1/what-ever in pre-season. Right at the edge. Simply because this is a fun intensity level. These days will form the skeleton.
It will be interesting to see how the curve looks like now. Did my last lactate ramp test 4 years ago. This was about when I bumped up my training to 18-25hrs/week. Since then I kept that volume.
It’s all about figuring out how much one can assimilate. This will be an exciting experiment for me.
Which lactate analyzer did you go for @sryke?
Thanks for sharing. So your plan is to ride 3-4 days right at the border of Z2/Z3 (=LT1/AeT). How long for each session?
18-25 hours of training is huge! My wife would not be impressed with me. My ‘wife threshold’ AKA my LT3 is around 12 hours. Any more than that and I get a steady build up of anger lactate from my LT3 which I can not process until I drop my hours on the bike 
Lactate Pro 2 … not so many options here, especially at the lower price range.
Yes, 3 to 4 right at whatever the curve tells me (e.g. it starts increasing from baseline … may rethink this if it is not a “fun” intensity. But it should be, based on where I think this will happen).
Indoors 3h, outdoors 4h. Depending on weather I will have to combine it with running, e.g. run for 90-120min outdoors and then hop on the trainer right after. However, given my life situation I have to be flexible, this is the key to keep the family happy.
Overall this is not too different to what I’ve done the previous years in pre-season. Difference is the target intensity and monitoring provided by the measurement.
I’ve done more stupid things in the past. Highlight was a low-carb, high-volume tempo block in December. This was really stupid.
I’m debating whether I should do something similar. I did some lab tests with INSCYD at the end of last year and did ca. 7 months worth of training(set up by coach) based on the results. Around March, based partly on ISM as well as few other coaches I’d heard on podcasts, I threw it all out the window and decided to max out my volume and ride mostly at high Z2, low Z3 and fat max. I’ve managed to sustain 18-20hrs/week without recovery weeks and most importantly, I’ve not been sick. My hard efforts were weekends in the mountains and I also did some block weeks of low cadence/high torque on some long climbs. I haven’t tested since Jan and don’t plan to. With winter coming I’m wondering if I should get a lactate analyzer just for the fun of it, or just keep bumping up my power based on HR and RPE. Training volume(bike) is capped at around 18hrs/week. I’ll also run twice a week(max 2 x 40mins) and strength training 2-3/week.
