One Hour Power
Comments
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CP and FTP will be essentially equivalent values provided the tests used to establish CP are of a long enough duration. Keep in mind that use of such a test protocol is a pretty reliable method used to establish FTP.Alex99 wrote:Alex_Simmons/RST wrote:
Yes, a well paced maximal effort ride of about an hour will have and "anaerobic" energy contribution of only around 1-2 percent. The shorter the test, the greater such non-sustainable energy metabolism contributes to supply the energy demand.OfficerDigby wrote:Obviously longer is better as the anaerobic sprint at the end is minimised.
It's quite OK to do this, provided you use at least two tests over different durations, e.g one of a handful of minutes and a longer one of between 20-30-minutes. By calculating the slope and intercept of the energy v duration plot from these tests you can then determine your "critical power", which will be analogous to FTP, and your "anaerobic work capacity", your non-sustainable energy capacity which is available to meet energy demand beyond such threshold (critical) power.OfficerDigby wrote:BTW how many people go anaerobic at end of ftp test to increase their numbers (is it not cheating!)
Typical values for such non-sustainable energy supply capacity, are in the 10kJ to 20kJ range, of course some people have a higher capacity and some lower. So when this non sustainable energy reserve is depleted during maximal well paced test effort of about 20-minutes, that represents approx 8W to 16W of the average power you can sustain. If you do a 20-min test and average, e.g. 240W, then non-sustainable energy reserves may be responsible for 3% to 7% of your power output (or more if your AWC is higher).
Alex, very interesting stuff, but I still find some of the definitions a little confusing. You describe Critical Power (CP) and "non-sustainable energy supply capacity" (same as W' in e.g. Golden Cheetah?) in a way that makes total sense to me. In my words, you have CP, which is this power level where you're on this metabolic tight-rope or threshold. You can ride at CP for a "long time" (the "long time" is not a fixed period of time. Efforts of over say, 5 minutes will be dominated by CP). You can deconvolute CP and W' by doing maximal field tests at e.g. 2 minutes and 15 minutes and fitting a model. e.g. Golden Cheetah tells me that I have a relatively low CP compared to my W' (as compared to other figures I've seen) and this is borne out in the types of race where I have done well.
I have thought of FTP as riding at CP for one hour, + W' spread over the hour. Reading your comments, I'm not sure how FTP differs from CP in your view. Once again, I don't know what FTP is :oops:
If you use overly short tests to establish CP (e.g. as is common in the scientific literature, i.e. tests of between 1-10 minutes) then the resulting CP value will tend to be somewhat higher than FTP (i.e. the maximum power one can sustain in a quasi-steady state without fatiguing for a long time, i.e. approximately an hour). And because of the hyperbolic function describing the work-duration relationship used by the CP paradigm, then by its very nature this means the W' ("AWC") value will be inflated somewhat. The difference for instance might result in CP value more akin to 20-min mean maximal power than what we might consider to be "threshold".
Using tests of 2 and 15 minutes is a bit borderline in that respect, which is why I'd suggest lengthening both and is why cherry picking data can be problematic if over time your CP is calculated from maximal data using quite different input durations (it's better to use a similar test protocol each time).0 -
Can I hijack because I don't want to create my own dumb ass thread.... What's considered decent FTP? I know everyone keeps talking about w/kg but as someone currently at 30% bodyfat that doesn't mean much to me. Just interested to know where my fitness lies currently as far as power is concerned.0
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How long is a piece of string?imafatman wrote:Can I hijack because I don't want to create my own dumb ass thread.... What's considered decent FTP? I know everyone keeps talking about w/kg but as someone currently at 30% bodyfat that doesn't mean much to me. Just interested to know where my fitness lies currently as far as power is concerned.
Decent for what? Body mass matters because W/kg (along with aerodynamics) is what determines your capability to maintain certain speeds, keep up with others in ride groups and so on. 200W @ 2W/kg is a completely different animal to 200W @ 3.5W/kg.
Some context:
The top male pro GC riders in grand tours will have an FTP in the 6W/kg range.
A young adult male with average VO2max, body mass, gross efficiency and well trained enough to have a lactate threshold at a reasonably typical fractional utilisation of VO2max will have an FTP of ~4W/kg.
Most lower category racers are in the 3W/kg to 5W/kg range.
2.5-3W/kg will mean you can get along at an enjoyable clip, riding with steady groups, tackle rides challenges and so on.
2W/kg and you can enjoy cruisy rides, commute OK and smell the roses. Racing at lower category levels unlikely.0 -
Alex_Simmons/RST wrote:
CP and FTP will be essentially equivalent values provided the tests used to establish CP are of a long enough duration. Keep in mind that use of such a test protocol is a pretty reliable method used to establish FTP.Alex99 wrote:Alex_Simmons/RST wrote:
Yes, a well paced maximal effort ride of about an hour will have and "anaerobic" energy contribution of only around 1-2 percent. The shorter the test, the greater such non-sustainable energy metabolism contributes to supply the energy demand.OfficerDigby wrote:Obviously longer is better as the anaerobic sprint at the end is minimised.
It's quite OK to do this, provided you use at least two tests over different durations, e.g one of a handful of minutes and a longer one of between 20-30-minutes. By calculating the slope and intercept of the energy v duration plot from these tests you can then determine your "critical power", which will be analogous to FTP, and your "anaerobic work capacity", your non-sustainable energy capacity which is available to meet energy demand beyond such threshold (critical) power.OfficerDigby wrote:BTW how many people go anaerobic at end of ftp test to increase their numbers (is it not cheating!)
Typical values for such non-sustainable energy supply capacity, are in the 10kJ to 20kJ range, of course some people have a higher capacity and some lower. So when this non sustainable energy reserve is depleted during maximal well paced test effort of about 20-minutes, that represents approx 8W to 16W of the average power you can sustain. If you do a 20-min test and average, e.g. 240W, then non-sustainable energy reserves may be responsible for 3% to 7% of your power output (or more if your AWC is higher).
Alex, very interesting stuff, but I still find some of the definitions a little confusing. You describe Critical Power (CP) and "non-sustainable energy supply capacity" (same as W' in e.g. Golden Cheetah?) in a way that makes total sense to me. In my words, you have CP, which is this power level where you're on this metabolic tight-rope or threshold. You can ride at CP for a "long time" (the "long time" is not a fixed period of time. Efforts of over say, 5 minutes will be dominated by CP). You can deconvolute CP and W' by doing maximal field tests at e.g. 2 minutes and 15 minutes and fitting a model. e.g. Golden Cheetah tells me that I have a relatively low CP compared to my W' (as compared to other figures I've seen) and this is borne out in the types of race where I have done well.
I have thought of FTP as riding at CP for one hour, + W' spread over the hour. Reading your comments, I'm not sure how FTP differs from CP in your view. Once again, I don't know what FTP is :oops:
If you use overly short tests to establish CP (e.g. as is common in the scientific literature, i.e. tests of between 1-10 minutes) then the resulting CP value will tend to be somewhat higher than FTP (i.e. the maximum power one can sustain in a quasi-steady state without fatiguing for a long time, i.e. approximately an hour). And because of the hyperbolic function describing the work-duration relationship used by the CP paradigm, then by its very nature this means the W' ("AWC") value will be inflated somewhat. The difference for instance might result in CP value more akin to 20-min mean maximal power than what we might consider to be "threshold".
Using tests of 2 and 15 minutes is a bit borderline in that respect, which is why I'd suggest lengthening both and is why cherry picking data can be problematic if over time your CP is calculated from maximal data using quite different input durations (it's better to use a similar test protocol each time).
Awesome. Thanks0 -
Alex_Simmons/RST wrote:How long is a piece of string?
Decent for what? Body mass matters because W/kg (along with aerodynamics) is what determines your capability to maintain certain speeds, keep up with others in ride groups and so on. 200W @ 2W/kg is a completely different animal to 200W @ 3.5W/kg.
Some context:
The top male pro GC riders in grand tours will have an FTP in the 6W/kg range.
A young adult male with average VO2max, body mass, gross efficiency and well trained enough to have a lactate threshold at a reasonably typical fractional utilisation of VO2max will have an FTP of ~4W/kg.
Most lower category racers are in the 3W/kg to 5W/kg range.
2.5-3W/kg will mean you can get along at an enjoyable clip, riding with steady groups, tackle rides challenges and so on.
2W/kg and you can enjoy cruisy rides, commute OK and smell the roses. Racing at lower category levels unlikely.
Thank you. There's hope for me yet. That means when I get to my goal weight of 90kg and manage to maintain my power I will be around 2.7.. not looking to race but do want to keep up with some of the faster group rides. At 255W currently so there is hopefully potential for me to improve that figure too.
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