Bear with me folks as I am a trifle confused with Low intensity training.
Been using the 3 zone HR principal for 3 months now and reading as much as I can about the principals of this form of training. However there does seem to be a lot of conflicting advice going on out there.
Stephen Seiler says that benefits of low intensity sessions kick in after about 60 minutes, so in a 90 minute Z1 work out the last 30 mins are those that are giving the desired effect. Whilst in Sleamaker & Browning’s book “Serious training for endurance athletes”, they seem to infer that 90 mins is a high intensity session.
Have I misunderstood this? Any thoughts???
2 Likes
I suppose it all depends on the individual and at what point they are in their training plan.
90 minutes at Z1 in a 3 zone model isn’t going to give much adaptation to an individual who is used to doing 5 hour endurance rides.
But last weekend for example was my first time out on an endurance ride after a 3 week break after having been badly off form the 6 weeks before I took a break. I was exhausted after an hour and there was nowhere my legs didn’t hurt. I was riding Z1/Z2 watts in a 6 zone model.
Listen to, or watch, the interview with Dr Inigo San Milan. He describes Z2 rides (Endurance level) for 90 minutes, 3 times per week as enough to illicit adaptation.
2 Likes
I’d forgotten about San Millan; probably because I have trouble understanding him. But I’ll listen to that video. Thanks Gerald. 
1 Like
I’m coming straight off the road and used to longer rides, so whilst I find 90 mins terribly boring, I’m not sure what the effect actually is. Whether it is what I am aiming for eg an increase in my base aerobic capacity or something else. It seems that the world and his wife all have different opinions 
Based on the FTP from 9 weeks earlier?
1 Like
No. Dropped my FTP 30 watts!! This happens me though and within literally a couple of weeks I’ll be fine again
You are right: there are all kinds of serious disputes about Z1 in a 3-zone model [endurance] riding.
But, if we accept the San Milan & Seiler principles, then what you are looking for is repeatable work, consistently done. Seiler has the observational evidence: what good people do is mostly Z1. San Milan has suggested a mechanism for why this works – builds mitochondria and their capacity to burn lactate. There are perhaps side benefits too, such as improvements in fat burning capacity.
As to how long: Seiler has suggested a way to find out if your ride was long enough to elicit adaptations: does your HR/Power ratio rise towards the end of the ride? If yes, you’ve gone long enough; if no, you need to go longer. Seiler has a podcast about this – something like ‘how long is too long’. There is nothing about 60 minutes or 90 minutes or anything else that is critical – it all depends on you and your stage of endurance development. Obviously, as a mature and non-professional athlete, you don’t want to be riding for 2, 3, 4 or more hours every ride, even if that’s how good your endurance is – but you do want to be pushing your endurance boundaries once a week or so.
The other thing that both San Milan and Seiler emphasise is that none of this riding is done to a power target. It’s either HR or breathing [can you still talk in sentences?].
If you follow such a prescription, then obviously you also need to maintain or raise your ability to put out high wattages. Z1 riding contributes to this by enabling you to burn the lactate that you produce above threshold. But you also need to have the neuromuscular adaptations and fast twitch fibre adaptations to produce that lactate in the first place. That is where the long Z2 or shorter Z3 intervals come in: once a week [perhaps more as you come closer to ‘race season’.
That’s my understanding of the model. None of this stuff is easy or cut-and-dried. Opinions differ, in both coaching and scientific circles. And it might be that the efficacy of all this depends on individuals. Good luck in your quest.
12 Likes
Yes, watched this. But it doesn’t answer the question as far as I heard about whether 90 mins is high intensity or low intensity
Thank you for this @Michael_Webber what you say makes sense. About Seiler, he does mention in one of his videos the 60/90 minute session, but can’t remember which one, I’ve listened to so many. San Millan also helped today. I’ve listened to him previously but never quite understood him, this video was much clearer. (perhaps because I wasn’t on a turbo trainer listening )
However just asking the question today helped focus my mind a lot more and the answers our riding colleagues gave also helped.
In perfect condition, with infinite amount of time, probably Seilers method and building the duration of rides while lookin at hr decoupling should be most beneficial. But if you have other responisibilties than cycling like work, family etc, you need some compromises. Rate of training is very important and it is hard to find time for 5 long rides during a week like pros do and even if you do you won’t find time to recover from those rides like pros do with all fancy recovery stuff and lack of work and other stressors. Most often you rise wattage a little and ride higher zone 1 ((3z system) but shorter
while keeping high frequency like 5-6 trainings a week. Actually in one of the interviews San Milan talks about his own training and lack of time. He rides around 1h and tries to make once a week longer ride but most of the time it doesn’ happen due to lack of time, so nothing unusuall and he defends those 1h rides as enough duration for mitochondria build.(yt: San Millan Peter Attia) I think more important than the duration of a single ride is gathering weekly load and properly building monthly load and overall training structure and frequency. And ofc quality of your training and recovery is crutial and often overlooked, sometimes you do more by quiting wine or beer and getting healthier sleep than riding half an hour longer, trying to maintain stable power output without many stops and coasting is beneficial too etc (@BrendanHouslerEVOQ who writes here sometimes has some good posts on his Evoq blog describing hot to improve riding efficiency)t Atthe end it all depend if you ride for fun, health, socials or you plan to race If you plan racing it usually comes with compromises from other side like no family or at least very understanding wife or partner, lower income but more hours on the bike, force instead of red but more massages and saunas and so on 
3 Likes
Ask yourself this: “how much recovery would you need if you did 90 minutes of high intensity, 3 times a week?”
90 minutes of low intensity 3 times a week is what ISM alluded to when ask how much Z2 riding. He also said that you could add some high intensity at the end of the ride.
This is normal practice for a lot of coaches I’ve discussions with; do the Z2 work first then HIIT at the end, rather than HIIT work first and then ride the rest of the time at low intensity.
When someone asks a coach, “how much…. ?” and the response from the coach is “it depends”, this is truly a valid answer. It does depend on the individual.
Yes, I am in agreement with all of your comments and have that under control…more or less 
However the confusion in my mind is whether 90 mins in Z1 is considered High or Low intensity. Time-wise, I suppose that 90 mins (on a turbo trainer) could be considered a hard session. But effort-wise also low intensity. Perhaps I (we) should be thinking subjectively? IE: RPE/Feel, was that effort a tough or easy one dependant on days form?
Thanks for your input @Lukasz_Pludowski . Luckily, I’m a pensioner so have all the time in the world and again luckily enjoy training, so a win/win situation for me. I live in Norway so with autumn storms and minus degrees I’m now more or less stuck inside on the turbo trainer.
Yes, I remember in one of Seilers Youtube videos him mentioning time in zone. I’m “tinkering” with this at present as I came indoors 2/3 weeks ago and went over from riding outside 3 days a week to riding 5 indoors. I think that was a mistake so have gone back to three and trying to balance High and Low intensity. But my understanding of that was confused when I read Sleamaker & Browning’s book where they talk about 90 mins as high intensity albeit in Z1. So, admittedly towards the end of a 90 minute Z1 session, I feel the effort and I see the HR decoupling. So is the thinking that this should be considered a High Intensity session?
I have a spin on that:
good people that do this for a living have 40-60 hours per week for “work”. Despite being very good, they cannot handle that many hours of intensity. So most of this time is comprised of the “filler” endurance rides, because this is still a bit better than doing nothing, while parts of the body recover from more productive training modalities.
Does not apply to the amateurs though…
Intensity and duration a separate from each other. So a 5h ride can be (and is most often) low intensity. A shorter ride will often be done at a higher intensity as part of a training plan or if done on an indoor trainer - but it doesn’t have to be.
Intensity can be described through IF (intensity factor, which is normalized power of the ride relative to FTP)
1 Like
60min and 90min is a DURATION, not “intensity”. Intensity can be measured in watts, or in HR, or in grade-adjusted-speed. Never in time.
2 Likes
The amount of intensity is relative to duration. While it’s not measured by duration, it cannot be isolated from duration, and frequency.
- intensity = how hard
- duration = how long
- frequency = how often
Volume is frequency and duration.
2 Likes
In his most recent videos, Seiler changed the terminology a bit. He’s no longer talking about HIT and LIT sessions but about 2 “buckets”. One for the hard sessions and one for the easy sessions.
That accommodates the question of @Stephen_Humlen-Grins . A Low Intensity session that is much longer then what you’re used to, can go in the ‘hard bucket’.
He’s absolutely correct that judgement should be based on RPE. The amount of decoupling can help quantify.
I’m not sure I am in complete agreement with you @Poul_Bentsen, as far as I can make out there is a point in any ride be it on a turbo or on the road when a Z1 ride becomes intense, at least for me. But my original question is do we recognise that and call it High intensity as Sleamaker & Browning seem to suggest? I don’t know, thats why I ask.