CP Testing

amaferanga

I've decided to use critical power testing with 5min / 12min tests to estimate FTP. I'm using 12min as this is how long it takes me to get up the longest continuous and suitable climb that's near enough for me to test on regularly.

The plan is to do the 5min test then pedal easily round a loop for about 15-20min and then do the 12min test on the same day. Just wondering whether it'd be better to do the two tests on different days so both are truly maximal as the 5min effort will obviously have some effect on the 12min effort that follows?

I guess it maybe doesn't matter as long as I'm consistent, but I am curious as to what others do.

Also, are 5min / 12min suitable durations or should I use something shorter than 5min?

And please don't suggest doing longer tests on the turbo - having started riding outside with my PM regularly again recently I've realised that my turbo power is 5-10% down on my road power, perhaps more for the shorter duration/higher power efforts.

Thanks.

magliaceleste

I do 20min / 3min to measure CP. I just make sure I do them in the same week, no way I could manage them on the same day. 3 mins at max is hard enough.

The result seems to be a very realistic FTP, if you know what I mean.

GiantMike

Personally I'd do longer rides on the Turbo....

...only joking.

I'd do the 5 and 12 on different rides. Otherwise you'll just think that the 12 was a low figure because you did the 5 first.

In fact, it might be worth doing the 5 and then the 12 on the first ride, and then the 12 on the second ride and comparing the 2 12s.

Alex_Simmons/RST

amaferanga wrote:

I've decided to use critical power testing with 5min / 12min tests to estimate FTP.

I would suggest a longer test than 12-min. 20-30-min would be better.

The closer test durations are, the greater the potential error in the slope (= CP ~= FTP).

joeyhalloran

Is this using the power curve that is calculated? is there a particular method for this or do you just upload a 3 min cp and a 20min cp (for example) and then let the software draw your power curve?

amaferanga

Alex_Simmons/RST wrote:

amaferanga wrote:

I've decided to use critical power testing with 5min / 12min tests to estimate FTP.

I would suggest a longer test than 12-min. 20-30-min would be better.

The closer test durations are, the greater the potential error in the slope (= CP ~= FTP).

I would love to do a 20-30min test, but 12min is the longest stretch of road within easy reach without significant downhill stretches and/or junctions / traffic lights / roundabouts. Having said that I could probably stretch it out by a few minutes if I include a short downhill stretch and pass through a village, but then there's a chance I could get held up. With my 12min route there's almost zero chance of any interruptions.

So would a 3min test be better than a 5min or will it make little difference? WIll using a 12min test instead of a 20min or 30min test likely overestimate or underestimate FTP or does it just depend?

SBezza

Is there not a 10m TT course nearby, although it will have a turn in it, it should still give you a good representation of what power you can produce for 20+ mins. They are normally choosen to avoid traffic lights, etc.

amaferanga

JoeyHalloran wrote:

Is this using the power curve that is calculated? is there a particular method for this or do you just upload a 3 min cp and a 20min cp (for example) and then let the software draw your power curve?

I think this is right. Or just use Golden Cheetah's CP calculator that allows you to put in any durations/power you want. I think the CP value reported in GC underneath the critical power curve just takes your all time best (or maybe just season best), so its not really much use.

amaferanga

SBezza wrote:

Is there not a 10m TT course nearby, although it will have a turn in it, it should still give you a good representation of what power you can produce for 20+ mins. They are normally choosen to avoid traffic lights, etc.

Dunno. Nearby needs to be within 30-40mins ride from where I work in Sheffield so I can test during the week. The further it is away the less likely I am to test regularly.

wastrel

Or actually do a local 'club 10' - always worth a few extra watts! - and do the 3/5 min effort a few days later. My understanding is that the long interval on the Golden Cheetah CP calc should be long enough to represent your aerobic capacity. I have not got the brain power to think whether it might under or over estimate, but I suppose the closer the two points are on a curve the greater the potential error when extrapolating.

FWIW when I do the CP like this, it's very close to my 'real' 1 hour TT effort FTP (not that the number is vaguely impressive either way). Happy 4th cat 'bunch fodder'

@ Joey - the GC software does the calc for you, you can choose any two suitable intervals.

Alex_Simmons/RST

amaferanga wrote:

I would love to do a 20-30min test, but 12min is the longest stretch of road ....

So would a 3min test be better than a 5min or will it make little difference? WIll using a 12min test instead of a 20min or 30min test likely overestimate or underestimate FTP or does it just depend?

Test venues are problematic in some rider locations. Test on a weekend when you have more time to travel somewhere more suitable?

When using the CP model as a guide to establish FTP, I personally recommend two tests. One of 4-6 minutes and another of 20-30-min. Preferably conducted within about a week of each other.

Down the Road

Rule 74:

Computers, GPS, PowerTaps, SRMs; If you are not a Pro, then you don’t need a SRM or PowerTap. To paraphrase BSNYC, an amateur cyclist using a power meter is like hiring an accountant to tell you how poor you are. As for Garmins, how often do you get lost on a ride? They are bulky, ugly and superflous. Ditch the HRM and ride on feel; little compares to the pleasure of riding as hard as your mind will allow. Cycle computers should be simple, small and mounted on the stem. And preferably wireless

amaferanga

Down the Road wrote:

Rule 74:

Computers, GPS, PowerTaps, SRMs; If you are not a Pro, then you don’t need a SRM or PowerTap. To paraphrase BSNYC, an amateur cyclist using a power meter is like hiring an accountant to tell you how poor you are. As for Garmins, how often do you get lost on a ride? They are bulky, ugly and superflous. Ditch the HRM and ride on feel; little compares to the pleasure of riding as hard as your mind will allow. Cycle computers should be simple, small and mounted on the stem. And preferably wireless

:roll:

Rules for ludites?

Down the Road

No why would you want to know how poor you are?

twotyred

llittle compares to the pleasure of riding as hard as your mind will allow.

Perhaps not but you'll be too knackered to do any meaninful training for the rest of the week.

amaferanga

Down the Road wrote:

No why would you want to know how poor you are?

Eh? Owning a power meter has nothing to do with comparing yourself to a pro.

What a stupid thing to say.

If you don't want / can't afford a power meter then don't criticise those that do/can.

Down the Road

What are you achieving by having one

SBezza

Down the Road wrote:

What are you achieving by having one

Training better and more precisely.

If you don't think a computer/power meter is needed for an amateur, then that is fine, but those of us that use a powermeter will know differently from experience rather than just speculate they are not required.

I could quite easily say a 5k bike is not needed by an amateur, I get by quite happily on alu bikes that costs a few hundred quid, but if someone wants/can afford a 5k bike, then they are within their rights to buy one, and not get criticised for having it.

There are different levels of amateur rider, just like there is for a pro, so it goes to say some will want to try and be the best they can.

amaferanga

Down the Road wrote:

What are you achieving by having one

It allows me to compare my ability objectively compared to where I was last week, last month, last year, etc. It allows me to train the way I want to train. It allows me to objectively track my training load. I could go on, but I can't be arsed.

Its not a magic bullet by any means, but if used intelligently it can have many benefits.

If nothing else I actually enjoy messing around with all the data after rides.

Funny how some folk are so against power meters. Have you ever owned one?

Down the Road

I don't need one as I can feel and see the differences. The data is meaningless for 99% of people.

Train with those faster than you and ride flat out and you will get better. Arse about with numbers and you can only improve relative to the start point and never realise your potential.

If you TT do you use it?

I suspect not and therefore like most owners you are wasting its real benefit

Ps HRM is the same for 99% of owners

SBezza

Down the Road wrote:

I don't need one as I can feel and see the differences. The data is meaningless for 99% of people.

Hard to feel a few percent in difference, and it is easy to feel you have got better, just because the weather is different

Train with those faster than you and ride flat out and you will get better. ars* about with numbers and you can only improve relative to the start point and never realise your potential.

Not always easy to find fast training partners at the times you can train, plus training alone is probably better, and you can't take a break from the wind etc.

If you TT do you use it?

I do actually, and it has help me become faster by actually being able to see that starting effort was probably way too high, based on feel.

amaferanga

Down the Road wrote:

I don't need one as I can feel and see the differences. The data is meaningless for 99% of people.

Train with those faster than you and ride flat out and you will get better. ars* about with numbers and you can only improve relative to the start point and never realise your potential.

If you TT do you use it?

I suspect not and therefore like most owners you are wasting its real benefit

Ps HRM is the same for 99% of owners

You feel and see difference subjectively. No-one says you should ignore these if you have a power meter, but at least you have some objective measures of performance to back up your feeling.

And in what way is the data meaningless to 99% of people? Can you point me to the research that's the basis for the statement?

Another one here that races with their PM btw. That's currently 2 from 2.

Anonymous

And me.

Anonymous

And me.

mattshrops

wow youve got a twin brother- hes almost identical

Down the Road

OK what is the final heart rate before your lactic threshold is met. and I am not taking 75% of Max as an answer.

Ps if you were riding at that and the pack was leaving you behind would you not just try harder and ignore the info?

Down the Road

NapoleonD wrote:

And me.

My point was you SHOULD TT with a power meter if you know what it means

SBezza

Down the Road wrote:

OK what is the final heart rate before your lactic threshold is met. and I am not taking 75% of Max as an answer.

Ps if you were riding at that and the pack was leaving you behind would you not just try harder and ignore the info?

This is inmaterial IMO, unless you have been to a lab to measure your lactic threshold, you simply do not know what it is, is this really any benefit to an amateur :? HR is only a guide, it will not be the same each time.

If you were riding in a pack, I would suggest not looking at the PM, and just watch where you are going. At least with a PM you would have the data in front of you showing you why you could keep up, or you blew.

A PM is a very useful training aid, some of us train with power, and do not ride by it constantly. In a TT I will use to measure my effort at the start, but during the TT I will race on feel, and download the data afterwards to see where improvements can be made, or where I went too hard and subsequently have to put in a lower effort so as not to blow.

As mentioned before a PM is not a magic bullet, but it provides a tool so you can measure your performance by, you simply can't measure your improvements based on HR.

I trained very successfully on HR last year, but since getting my PM, I have realised the limitations with HR, and RPE. Actually I was doing my intervals with turbo power rather than HR, but all my road rides were done with HR.

Alex_Simmons/RST

Down the Road wrote:

I don't need one as I can feel and see the differences. The data is meaningless for 99% of people.

Train with those faster than you and ride flat out and you will get better. ars* about with numbers and you can only improve relative to the start point and never realise your potential.

If you TT do you use it?

I suspect not and therefore like most owners you are wasting its real benefit

Ps HRM is the same for 99% of owners

Troll.

When you have something constructive to add to the OP's question about Critical Power testing, then we'd love to hear from you.

nmcgann

amaferanga wrote:

Down the Road wrote:

What are you achieving by having one

It allows me to compare my ability objectively compared to where I was last week, last month, last year, etc. It allows me to train the way I want to train. It allows me to objectively track my training load. I could go on, but I can't be arsed.

Its not a magic bullet by any means, but if used intelligently it can have many benefits.

If nothing else I actually enjoy messing around with all the data after rides.

Funny how some folk are so against power meters. Have you ever owned one?

+1 to that. A PM tells you exactly where you are...if only it would do the training for me

I've pretty much given up on CP tests as a prediction of FTP, they just don't tell me anything useful and I find them incredibly stressful and failure-prone. I set target training levels based on what I can do routinely in training and races (I race with a PM too) as that is a more realistic measure for me than a test.

I also wouldn't discount HR as some PM purists do - I find the HR I can sustain for different lengths of time when race-fit is predictable and this doesn't seem to change much. On my best rides I'm doing almost identical HR profiles to poorer ones, there's just a higher power output (and a better power vs time profile).