LT, FTP and 2*20 Question

markwb79

I am for ever getting confused about the above!

Is this correct?
LT - Lactate Threshold, often tested by a TT or 20mins flat out?
FTP - Functional Threshold? Is this the power you can hold for an hour? Calculated as 95% of LT?
2*20 Intervals - Are these done at (or just above) FTP?

Also, if you are not regularly doing tests, but training regularly (guessing Cat2 level). Do you keep doing 2*20 at your last tested FTP? Or is there a % increase (or decrease) you can assume?

Only recently bought a turbo with power, so plan to test more regularly. But I expect it to be max every 2 months.

Thanks
Mark

bigpikle

LT - lots of different definitions for this depending on where you look and who you read

FTP - defined as the max power you can sustain for an hour UNDER IDEAL CONDITIONS. Its often calculated as 95% of 20 min power but this is a bit of a guess as for many people it could be more or less of this %

2x20's - thats just a interval description. Ride them as hard or easy as you like depending on your overall programme, goals and other sessions. There is a common misconception that you have to ride at FTP to improve FTP, but thats not true, so its common to ride these at 85-90% of FTP and do more sessions

Theres a good chance you wont be able to maintain your outdoor power levels for the same duration indoors, so do an indoor 20 min 'test' and set your levels from that. Make sure you have a BIG fan for cooling or you'll probably be even further off your power levels...

ric/rstsport

LT is generally defined within the literature as the intensity that either elicits 1 mmol/L increase over exercise baseline level of lactate (which would be 2 point something mmol/L) or the intensity that elicits a fixed 2.5 mmol/L. These intensities are somewhat easy to moderate, in as much as they could be sustained maximally for 3 to 4 hours. They're about 10 to 15% lower power than that which can be maintained maximally for about an hour. Your LT would be measure in power output (W) when cycling (or as velocity in running). You need to have blood taken to measure your LT. And, heart rate has nothing whatsoever to do with LT (not that you mentioned that, i'm just saying). Usually, LT would be measured while performing a slow incremental ramp rate, with blood being drawn every step up. Accordingly, LT is NOT tested via a TT or a 20-min maximal test. However, there would be an extremely good correlation between LT and TT power (or a 20-min test). That is, the higher your LT the higher your TT power.

FTP is the maximal power you could sustain for about an hour. It would be higher than LT. Probably, by 10 - to - 15%. FTP is not a real 'physiological' measure. The closest is probably maximal lactate steady state (MLSS) but even this would be below FTP. This is because lactate could continually rise during a ~40km TT/25-mile/1 hour TT.

FTP should NOT be taken as 95% of 20-minute power. It will vary (quite a lot) depending on how much 'anaerobic power' you have.

2*20 is a set of intervals. These may, or may not be of any use to the rider you are or the cycle sport(s) you do. They should be ridden at about TT power (probably within 5%). I wouldn't suggest riding them at 85 - 90% as this is significantly lower than intended for what i *think* you have in mind. At 85 - 90% you're down to what some people call the 'sweetspot' (and while you can definitely do 2 x 20 at sweetspot, it would be more normal to be aiming for at least 60-mins of sweetspot (although this would of course depend on your goals and fitness etc) going up to 2 or 3 hrs.

Presumably (?) you'll be riding your turbo frequently and seeing how you ride as you ride. so, you may need to do 2 x 20 hard in training and you could see how you're improving then.

Ric

ChrisSA

To expand on what Ric has said, a 20 minute test will often have a few bursts to open the legs, and a hard 5 minutes to deplete the aerobic system. Then after a short RI the 20 minutes is hit. it's 95% of that 20 minute average power that can be assumed to be FTP (and not just 95% of your best 20 minute power).

Look up Allen and Coggan.

ric/rstsport

ChrisSA wrote:

To expand on what Ric has said, a 20 minute test will often have a few bursts to open the legs, and a hard 5 minutes to deplete the aerobic system. Then after a short RI the 20 minutes is hit. it's 95% of that 20 minute average power that can be assumed to be FTP (and not just 95% of your best 20 minute power).

Look up Allen and Coggan.

although to be fair i feel that would lead to an underestimated FTP. Although Coggan is the secondary author on the book, it's not what he'd suggest using (iirc). If you open up with a full on 5-min effort it'll just be too strenuous...

There are other ways of predicting FTP. I like this article best from Alex http://alex-cycle.blogspot.co.uk/2008/0 ... -sins.html

markwb79

Thank you very much for your replies.

Very interesting stuff. I understand most of it, and it is mostly how I thought.

Ric - You say that FTP would be higher than LT? But you also say LT and TT power (20min test) are about the same. I thought that TT power (20min test) would always be higher than FTP?

If I wanted to base my training on FTP, whats the best way to test it then?

A year ago I had the test you describe with the blood taken during a ramp test. My LT (this is off memory) came out at 260watts. I will do the same test in a months time.

I am resorting to riding my turbo more because the local velodrome nearly burnt down last week.

Thanks again
Mark

ric/rstsport

Markwb79 wrote:

Thank you very much for your replies.

Very interesting stuff. I understand most of it, and it is mostly how I thought.

Ric - You say that FTP would be higher than LT? But you also say LT and TT power (20min test) are about the same. I thought that TT power (20min test) would always be higher than FTP?

If I wanted to base my training on FTP, whats the best way to test it then?

A year ago I had the test you describe with the blood taken during a ramp test. My LT (this is off memory) came out at 260watts. I will do the same test in a months time.

I am resorting to riding my turbo more because the local velodrome nearly burnt down last week.

Thanks again
Mark

I don't think i wrote that. i'm fairly certain i wrote LT is less than FTP is less than 20-min power.

best way to test it is to do a ~40km TT. or see the link to alex's blog that i posted above.

yeah saw that about the amsterdam velodrome... didn't even know there was one in amsterdam! only been to the one in apeldoorn

ric

Alex_Simmons/RST

What Ric is saying is it's the same primary underlying physiological adaptations which improve power at LT and FTP, not that power at LT and FTP are the same (they're not).

In practical terms what that means is if you are already measuring power, then LT testing is largely redundant.

Coggan's Level 4 power range is also called lactate threshold, not because that's the intensity level where LT occurs (it's not - LT typically somewhere in Level 3 - Tempo), but because it's a power level that primarily targets and most emphasises adaptations that improve LT. As Andy would say, "the levels are descriptive, not prescriptive".

That's not to say it's the only power level that targets LT adaptations (it's not).

bahzob

There is a real danger in all the above that you can fail to see the wood for the trees and, while I am a great believer in power based training I get a bit worried when I see a thread like this.

It really doesn't matter what levels are called. To a large extent these only exist as a hangover from before when power meters were available.

Knowing what your FTP is handy for bragging rights but really isn't much use beyond that once you have accumulated a reasonable amount of actual power data. (the exception may be it's handy if you have a tool like WKO to help manage training load but here it's hugely dependent on personal variables.)

You can only quote a FTP number and understand what it means in the context of what your race is. As an e.g. a rider who wants to win the tour de france will want to hit around 6.5W/kg FTP but that's only because the tour has a high emphasis on events around FTP duration (TTs and long climbs). This would be of far less relevance in predicting who may win a one day classic, which may be based around the ability to hit and repeat high short duration efforts.

At the end of the day what you are interested in knowing is how much power you can sustain for a given period of time. This is what will determine your training zones and be a good predictor of outcomes. Just knowing FTP is not really enough for this, 2 riders with the same FTP may still train at different zones/have different results.

If you have access to a power meter rather than base everything on one number it makes far more sense imo to have a set of 4-5 PBs that record what power you can sustain for given intervals e.g.
Watts you can sustain for 5s/1min/5min/20min/1 hour/4 hour
(* to be precise the PB should be W/kg)

For each you would have a test protocol that works for you. e.g. for above might be
5s local sprint you know well or best effort from a race or competitive local group ride
1/5 min PBs up local climbs/max efforts from races
20 min 10TT
1 hour 25 TT
4 hour 100TT or equivalent

You can use these to set all the training zones you need. Also as a benefit having several different PBs can be a good motivator and looking at how these compare to peer group average may give you an insight to where you are strong/weak which in turn may help decide where you should focus training or which events you should enter,.

Back to OP: same applies to turbo. If are new to the turbo just do some max efforts of 5s, 1 min, 5min and 20 min. Just record what these are and aim to beat them in future. You can base your training off them quite easily just by varying power/time and doing as intervals. e.g, if you can do 250W for 20 mins as a PB try doing 250W for 3x15 mins or 2x20min@240W with 5 mins RBI. After only a few sessions at the various intervals you will soon get a feeling for how to set intensities.

Trev The Rev

Bahzob talking a lot of sense here.

I think there can be too much jargon speak based around zones and FTP. In some ways training with a power meter comes full circle to training by feel and distance, time & speed. The power figure is just more accurate because you don't have the variables of wind and terrain.

Road races and track races require a very different power profile to 25 mile TT profile.
The ability to sustain power over relatively short time periods then recover is what matters, as Bahzob says, knowing your power (or performance measured differently) over 30 seconds, a minute, 5 minutes etc etc, is what matters - plan training around this. If you do 25 mile TTs then yes plan your training based on your best 50 to 60 minute power.

In general I think there are too many zones, too much jargon, too much obsession with power meter data and not enough specific hard training, which actually improves performance over the time periods which really matter, followed by appropriate recovery and or rest..

Wouldn't mind betting there are blokes out there who have improved their FTP considerably (according to power meter data) but oddly have not set a PB or improved their racing compared to their peers. Collect enough data and eventually you will get a bigger measurement. This is not the same as improved performance in a race.

Tom Dean

bahzob wrote:

For each you would have a test protocol that works for you. e.g. for above might be
5s local sprint you know well or best effort from a race or competitive local group ride
1/5 min PBs up local climbs/max efforts from races
20 min 10TT
1 hour 25 TT
4 hour 100TT or equivalent

FTP is just a reference point, training levels are based around that on physiological principles. They are not meant to be precise, discrete zones.

The problem with having your 6 reference points is how to use them.

Trev The Rev

Tom Dean wrote:

bahzob wrote:

For each you would have a test protocol that works for you. e.g. for above might be
5s local sprint you know well or best effort from a race or competitive local group ride
1/5 min PBs up local climbs/max efforts from races
20 min 10TT
1 hour 25 TT
4 hour 100TT or equivalent

FTP is just a reference point, training levels are based around that on physiological principles. They are not meant to be precise, discrete zones.

The problem with having your 6 reference points is how to use them.

How is not that complicated. Too many people think it is.

Tom Dean

It is much more complicated than using a single reference point, an established system based on sound principles, and a bit of trial and error.

It certainly doesn't help in the example you gave of recovery in road races, what does a 1 or 5 min PB tell you about that?

Trev The Rev

Tom Dean wrote:

It is much more complicated than using a single reference point, an established system based on sound principles, and a bit of trial and error.

It certainly doesn't help in the example you gave of recovery in road races, what does a 1 or 5 min PB tell you about that?

Specificity - You would work on doing tests from the sort of pace or power you would be doing in a race. A 1 minute or 5 minute PB still tells you a lot about the riders profile, ability and progress. FTP based on 60 minutes or a theoretical FTP based on other time scales and percentages only tells you about one aspect.

As you mentioned recovery - recovery from intense efforts is something worth understanding and improving. Often the race winner is he who recovers best from efforts and is able to keep repeating them. The ability to burn one more match than the rest, can be more important than the intensity of each match.

Tom Dean

Of course the PB tells you about ability, it does not tell you how to train. Knowing a power PB for a certain time does not make your training more race-specific.

bahzob is saying you can better establish training levels with 6 different PBs, rather than 1 (FTP) but how? He has written a long post but this, the useful piece of information, is missing.

I'm not saying this cannot be true in principle, but it would be more complicated than what most people currently do.

Trev The Rev

Tom Dean wrote:

Of course the PB tells you about ability, it does not tell you how to train. Knowing a power PB for a certain time does not make your training more race-specific.

bahzob is saying you can better establish training levels with 6 different PBs, rather than 1 (FTP) but how? He has written a long post but this, the useful piece of information, is missing.

I'm not saying this cannot be true in principle, but it would be more complicated than what most people currently do.

How complicated depends on your overall approach. If you applied the over complicated methods many people do based on FTP then it would be complicated.

Can't see how taking into account a riders profile is complicated. Even based on one FTP number different riders 1 minute power or 5 minute power varies greatly even if they have the same 60 minute FTP. You have to take the individual riders abilities into account. I think this is reasonably well covered in Allen & Coggan's book.

You certainly need to know a riders anaerobic ability which does not correlate well with FTP.

Tom Dean

I am not saying a rider's strengths and weaknesses should not be taken into account when deciding how to train.

markwb79

Confused.com

mattshrops

Surely the cp curve available in Goldencheetah(and no doubt wko) gives you these data reference points anyway?
And then depending on which workput you do (i.e. which length of interval you target) you then work on improving those figures. If you have specific targets in mind , then you concentrate on the most relevant and/or weakest areas?
Pretty basic power meter usage- no?

bahzob

mattshrops wrote:

Surely the cp curve available in Goldencheetah(and no doubt wko) gives you these data reference points anyway?
And then depending on which workput you do (i.e. which length of interval you target) you then work on improving those figures. If you have specific targets in mind , then you concentrate on the most relevant and/or weakest areas?
Pretty basic power meter usage- no?

Precisely. If you have access to a power meter then you really should be using a tool where you can keep a history of your rides, like WKO and Goldencheetah (I have no experience of the latter).

You will very quickly get a picture of how your power output capacity varies with interval duration and this, together with the demands of the events you prefer will determine how you should train.

Fundamentally it will give you personalised information that a blunt FTP test cannot do.

This is all you need. Knowing FTP/LT whatever does not really add anything into this, save explaining why it is that you may feel some certain ways during workouts.

Trev The Rev

bahzob wrote:

mattshrops wrote:

Surely the cp curve available in Goldencheetah(and no doubt wko) gives you these data reference points anyway?
And then depending on which workput you do (i.e. which length of interval you target) you then work on improving those figures. If you have specific targets in mind , then you concentrate on the most relevant and/or weakest areas?
Pretty basic power meter usage- no?

Precisely. If you have access to a power meter then you really should be using a tool where you can keep a history of your rides, like WKO and Goldencheetah (I have no experience of the latter).

You will very quickly get a picture of how your power output capacity varies with interval duration and this, together with the demands of the events you prefer will determine how you should train.

Fundamentally it will give you personalised information that a blunt FTP test cannot do.

This is all you need. Knowing FTP/LT whatever does not really add anything into this, save explaining why it is that you may feel some certain ways during workouts.

Constructive question. If data is obtained primarily from training rides which would be made at very variable efforts, is there a danger of basing training on underestimated power outputs?

Tom Dean

Not if you are trying sessions like this I guess!

bahzob wrote:

if you can do 250W for 20 mins as a PB try doing 250W for 3x15 mins

Trev The Rev

Tom Dean wrote:

Not if you are trying sessions like this I guess!

bahzob wrote:

if you can do 250W for 20 mins as a PB try doing 250W for 3x15 mins

It would depend on how hard you were trying when you set your 20 min PB.

bahzob

Trev The Rev wrote:

bahzob wrote:

mattshrops wrote:

Surely the cp curve available in Goldencheetah(and no doubt wko) gives you these data reference points anyway?
And then depending on which workput you do (i.e. which length of interval you target) you then work on improving those figures. If you have specific targets in mind , then you concentrate on the most relevant and/or weakest areas?
Pretty basic power meter usage- no?

Precisely. If you have access to a power meter then you really should be using a tool where you can keep a history of your rides, like WKO and Goldencheetah (I have no experience of the latter).

You will very quickly get a picture of how your power output capacity varies with interval duration and this, together with the demands of the events you prefer will determine how you should train.

Fundamentally it will give you personalised information that a blunt FTP test cannot do.

This is all you need. Knowing FTP/LT whatever does not really add anything into this, save explaining why it is that you may feel some certain ways during workouts.

Constructive question. If data is obtained primarily from training rides which would be made at very variable efforts, is there a danger of basing training on underestimated power outputs?

To an extent yes. Which is one reason that having a power meter is such a great training tool. You can (I would say should) be using it in races. This will give you good information about what your ultimate capacity is when pushed to the limit and help understand what happened which will in turn drive training.
- In a road race how hard and frequent accelerations are plus what your max sprint power is. These are often what ends up determining results so are what should be trained for.
- In a TT seeing how power varied with time which should help pacing strategy. So if you find you are trailing off at the end then negative split training would be a good idea.

However this doesn't alter the case here. I don't quite understand the assumption training rides = very variable data.

If rides are training rides then they should have a focus and this focus will be specific. So a given session may include an attempt at a 20minute PB and this should be done as if it were a race. The end power may be slightly down on what you would have achieved in the real thing but will still be perfectly sufficient to set zones and measure progress.

If you can sustain 300W for 20 mins in training conditions then you know a starting target for 2x20min in the same conditions is going to be around 280-295W. (it is impossible to be precise about exactly what the absolute value will be, there are to many individual variables.)

Try this and the first session will tell you if the target is ambitious or not, subsequent tries will fine tune this. You should find that you establish a level you can repeat and then start increasing power. After a few sessions try to set a new 20min PB. Hopefully it will be a bit more than 300W this time. After you have repeated this cycle a few times trying to set the new PB will feel quite close to a "real" race.

bahzob

Just to be clear PB = "Personal Best". By definition this means if you are doing a PB attempt you are going as hard as you possibly can as the objective is to go faster than you have ever done in your life.

Ofc this may well be affected by time and tide and where you are in the training year.

So, hopefully without adding too much complexity.

At the start of a new training year you can do some tests to set some "SBs" (season best). These will most likely be short of PBs, though the difference will be interesting. SBs will determine training zones and eventually, hopefully SBs will become new PBs as the season progresses.

If they do not it will be a little depressing but informative. Relevant to my earlier point is that it's quite possible you could set a new PB for 60 min power but fail to improve 1 min power. The impact of this will depend on the types of events you compete in, it won't matter much if you TT but may well explain why road races didn't go so well.

Trev The Rev

Thanks, I'm with you.

I have seen 1 min power improve and 20 min remain static - which was expected given the training I was doing but I was hoping for an improvement over 20 min as a freeby.

One reservation I have about power data (not that I don't think the data should be recorded) is the fact that the watts numbers show power output but do not show how hard the rider is working to achieve that power.

Tom Dean

bahzob, all you are doing is a PB test, then training x watts below that, based on trial and error. Why is a 20 min MAX a better basis for 20 min INTERVALS than FTP? I would argue the higher end of the workouts you propose are way over ambitious which suggests you are just plucking figures out of the air.

lef

Trev The Rev wrote:

Thanks, I'm with you.

I have seen 1 min power improve and 20 min remain static - which was expected given the training I was doing but I was hoping for an improvement over 20 min as a freeby.

One reservation I have about power data (not that I don't think the data should be recorded) is the fact that the watts numbers show power output but do not show how hard the rider is working to achieve that power.

My understanding is heart rate shows the effort, power is the output of that effort. Until recently I though FTP and resulting power zones was everything. However after a change in coaching I believe what is just as (more?) important is how efficiently you are creating that power and what energy systems you are using which other testing has pinpointed.

The longer I train with power I realise though important it is just a piece in the puzzle. At the moment I am mainly using power to ensure that durations are kept constant (almost to the watt when on rollers) yet focusing primarily on specific heart rate zones based on lactate threshold identified from gas analysis and not from a power output.

mattshrops

Trev, from what i understand the top of your cp curve is effectively your pb's at whatever time you wish to look at.

So during a training run you could set a power pb for 90 mins, but during that 90 mins you were obviously nowhere near your pb for 60, 30, 20 mins etc. You just take the relevant numbers at the relevant time intervals.

From that specific tt training is simple- target time and increase power(hopefully)

Other forms of racing more complicated, so constant bursts, sprinting power etc.

Bahzob - isnt ftp just a reference point along that cp curve. I agree we shouldn't get too hung up on that particular figure(unless our target is only 25mile TTs) but otherwise there would be infinite numbers along the curve. Ftp puts us at one point which provides useful reference for a lot of race uses(25tt, 60 min crits etc)

Its not the full story but still of good use.

Trev The Rev

lef wrote:

Trev The Rev wrote:

Thanks, I'm with you.

I have seen 1 min power improve and 20 min remain static - which was expected given the training I was doing but I was hoping for an improvement over 20 min as a freeby.

One reservation I have about power data (not that I don't think the data should be recorded) is the fact that the watts numbers show power output but do not show how hard the rider is working to achieve that power.

My understanding is heart rate shows the effort, power is the output of that effort. Until recently I though FTP and resulting power zones was everything. However after a change in coaching I believe what is just as (more?) important is how efficiently you are creating that power and what energy systems you are using which other testing has pinpointed.

The longer I train with power I realise though important it is just a piece in the puzzle. At the moment I am mainly using power to ensure that durations are kept constant (almost to the watt when on rollers) yet focusing primarily on specific heart rate zones based on lactate threshold identified from gas analysis and not from a power output.

Interesting. Have you found the relationship between lactate threshold identified by gas analysis and heart rate stable? I assume you would expect lactate threshold to be reached closer to maximum heart rate as you progress and do regular tests to re set the heart rate levels?

Trev The Rev

mattshrops wrote:

Trev, from what i understand the top of your cp curve is effectively your pb's at whatever time you wish to look at.

So during a training run you could set a power pb for 90 mins, but during that 90 mins you were obviously nowhere near your pb for 60, 30, 20 mins etc. You just take the relevant numbers at the relevant time intervals.

From that specific tt training is simple- target time and increase power(hopefully)

Other forms of racing more complicated, so constant bursts, sprinting power etc.

Bahzob - isnt ftp just a reference point along that cp curve. I agree we shouldn't get too hung up on that particular figure(unless our target is only 25mile TTs) but otherwise there would be infinite numbers along the curve. Ftp puts us at one point which provides useful reference for a lot of race uses(25tt, 60 min crits etc)

Its not the full story but still of good use.

CP curve? Critical power curve? Golden Cheetah? Is this created in software from data downloaded from all your rides, training and racing? Or do you set PBs specifically?