Is 4w/kg that impressive?
pastryboy
Posts: 1,385
I was just skimming a forum I don't post on an saw a comment:
I've done over 4 w/kg on a 20 min test on a wattbike. I've watched some videos of cat 3/4 races showing the speeds people are holding and I wouldn't expect to win any of them.
I know about the Coggan chart but in practice is 4 w/kg actually anything special?
if you genuinely have an FTP of over 4w/kg you should really be racing at Cat 2+ level.
I've done over 4 w/kg on a 20 min test on a wattbike. I've watched some videos of cat 3/4 races showing the speeds people are holding and I wouldn't expect to win any of them.
I know about the Coggan chart but in practice is 4 w/kg actually anything special?
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I wouldn't say it's special, but it's not too shabby either.0
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I was just skimming a forum I don't post on an saw a comment:if you genuinely have an FTP of over 4w/kg you should really be racing at Cat 2+ level.
I've done over 4 w/kg on a 20 min test on a wattbike. I've watched some videos of cat 3/4 races showing the speeds people are holding and I wouldn't expect to win any of them.
I know about the Coggan chart but in practice is 4 w/kg actually anything special?
Ah, I understand your confusion. Cat 2 actually isn't anything special.0 -
bear in mind that 4w/kg ftp is based on average power over an hour, not 20 mins, you can extrapolate but there's a fair margin of errormy bike - faster than god's and twice as shiny0
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Thanks for starting this thread, I had a very similar question!
Did some lab testing recently: a max test which gave me a max HR of 196, peak power of 396 watts and a VO2 max of 62.6. (Background - this was for a uni study which was looking at TT performance after overnight fasting so I did three time trials after three different drinks to see if there was much difference in performance. From the max test results I was given a Kj target to hit, the theory being that if I rode at 80% power I would hit said target in 20 mins dead, obviously finish quicker by going faster/harder.)
My best result was just over 18 1/2 mins at an average of 343 watts: I extrapolated (blind guessed!) that downwards to 335 watts for 20 mins which at a weight of 69.4 kilos gives a 20 min w/kg of 4.82 and a 60 min w/kg of 4.47 (I've taken 7.5% off the 20 min figure).
Now, I've always thought that I've got a fairly decent engine but this is the first time I've got to test it in a lab, and I can't quite believe the results against, for example, Coggan's power chart. I mean, I do a 4-5hr ride every six weeks or so, a few 2-3hr hilly / interval rides a month and I commute to work 7-10 miles each way fortnightly. Have done a few evening 10s with a best time of 23.55 on a pretty flat course (A10/11) and I want to take a chunk off that next summer.
Two questions:
1) have I done my sums right, because I just don't see myself as being in that sort of place on the Coggan chart;
2) if said sums are right, then what would be a sensible (yet stretch) target for lowering my 10 time? One minute off? Two? (I know there are other variables to consider!)
Thanks for your time
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Did some lab testing recently: a max test which gave me a max HR of 196, peak power of 396 watts and a VO2 max of 62.6.
[...] Have done a few evening 10s with a best time of 23.55 on a pretty flat course (A10/11) and I want to take a chunk off that next summer.
Two things:
1. Your time in a flat TT depends more on your watts/CdA than on your watts alone.
2. Note the correlation between VO2Max and 40 km TT time (on a flat sea-level course but with unknown wind) for these "elite" road cyclists.
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you need to interpret the chart with care, it's not as simple as x w/kg ftp means y, for instance...
for tt on the flat, power/weight ratio is less important than absolute power vs. drag (edit: as above), unlike races with a lot of climbing
a lot of uk road racing tends to be fairly flat circuits or crits, where being able to hand the repeated accelerations is also important
this explains a little more about interpretation...
http://home.trainingpeaks.com/blog/article/power-profilingmy bike - faster than god's and twice as shiny0 -
Thanks for starting this thread, I had a very similar question!
Did some lab testing recently: a max test which gave me a max HR of 196, peak power of 396 watts and a VO2 max of 62.6. (Background - this was for a uni study which was looking at TT performance after overnight fasting so I did three time trials after three different drinks to see if there was much difference in performance. From the max test results I was given a Kj target to hit, the theory being that if I rode at 80% power I would hit said target in 20 mins dead, obviously finish quicker by going faster/harder.)
My best result was just over 18 1/2 mins at an average of 343 watts: I extrapolated (blind guessed!) that downwards to 335 watts for 20 mins which at a weight of 69.4 kilos gives a 20 min w/kg of 4.82 and a 60 min w/kg of 4.47 (I've taken 7.5% off the 20 min figure).
Now, I've always thought that I've got a fairly decent engine but this is the first time I've got to test it in a lab, and I can't quite believe the results against, for example, Coggan's power chart. I mean, I do a 4-5hr ride every six weeks or so, a few 2-3hr hilly / interval rides a month and I commute to work 7-10 miles each way fortnightly. Have done a few evening 10s with a best time of 23.55 on a pretty flat course (A10/11) and I want to take a chunk off that next summer.
Two questions:
1) have I done my sums right, because I just don't see myself as being in that sort of place on the Coggan chart;
2) if said sums are right, then what would be a sensible (yet stretch) target for lowering my 10 time? One minute off? Two? (I know there are other variables to consider!)
Thanks for your time
Im pretty shocked if your pb is only that if you can pump out those figures. I did a 23.30 on a road bike without aero bits before I had a PM. I cant imagine I was stronger back then and my FTP is only 270 at 70kg.0 -
Thanks for starting this thread, I had a very similar question!
Did some lab testing recently: a max test which gave me a max HR of 196, peak power of 396 watts and a VO2 max of 62.6. (Background - this was for a uni study which was looking at TT performance after overnight fasting so I did three time trials after three different drinks to see if there was much difference in performance. From the max test results I was given a Kj target to hit, the theory being that if I rode at 80% power I would hit said target in 20 mins dead, obviously finish quicker by going faster/harder.)
My best result was just over 18 1/2 mins at an average of 343 watts: I extrapolated (blind guessed!) that downwards to 335 watts for 20 mins which at a weight of 69.4 kilos gives a 20 min w/kg of 4.82 and a 60 min w/kg of 4.47 (I've taken 7.5% off the 20 min figure).
Now, I've always thought that I've got a fairly decent engine but this is the first time I've got to test it in a lab, and I can't quite believe the results against, for example, Coggan's power chart. I mean, I do a 4-5hr ride every six weeks or so, a few 2-3hr hilly / interval rides a month and I commute to work 7-10 miles each way fortnightly. Have done a few evening 10s with a best time of 23.55 on a pretty flat course (A10/11) and I want to take a chunk off that next summer.
Two questions:
1) have I done my sums right, because I just don't see myself as being in that sort of place on the Coggan chart;
2) if said sums are right, then what would be a sensible (yet stretch) target for lowering my 10 time? One minute off? Two? (I know there are other variables to consider!)
Thanks for your time
1. Racing determines your race category, nothing else. All the power profile tables show is the power ranges typical for riders that race in those categories but to determine your race category, you race. That's because race category is a function of many things aside from your power profile.
2. Others have mentioned that W/m^2 is the primary factor to work on along with pacing skills.
Not sure if your TT tests were also in the lab, and if so it's unlikely to closely replicate outdoor ride times as aerodynamics is generally not well accounted for on indoor erg machines.
As to your testing: a VO2max of 62.6ml/kg/min at 69.4kg (4.34l/min).
Assuming you are at the top end of Gross Efficiency (~24%) and probably a slow twitch animal, a fractional utilisation of VO2max at threshold of 85% would be required for a threshold power of ~4.5W/kg. That doesn't leave a lot of room to move unless your VO2max is lifted further, although it's possible to approach 90% fractional utilisation. Lifting that to 88% would add ~11W to threshold, which if it also lifted 10-mile TT power a similar amount is worth ~ 20 seconds in a 10-mile TT at your power/aero.
If you are generating in the vicinity of 330-340W for a 10-mile TT and your time is 23:55 on flat course, then assuming conditions were not awful it suggests the largest and juiciest low hanging fruit is improvement with aerodynamics. 335W at an air density of 1.2kg/m^3 implies a CdA in the vicinity of 0.33 - 0.34m^2, which is road bike territory.
Aerodynamics requires experimentation and testing to ascertain improvements. There are several ways to do that, and if you are newish to the sport, it's quite likely you can attain good speed improvements via this path. It also requires commitment to the cause. There are a small number of things that will pretty much always work (e.g. deep section wheels, well fitted aerobars, tight skinsuit, good aero helmet), but the biggest factor is your position on the bike.
Pacing also matters, although aerodynamics is your primary issue if TT performance is your main aim.0 -
Thanks for starting this thread, I had a very similar question!
Did some lab testing recently: a max test which gave me a max HR of 196, peak power of 396 watts and a VO2 max of 62.6. (Background - this was for a uni study which was looking at TT performance after overnight fasting so I did three time trials after three different drinks to see if there was much difference in performance. From the max test results I was given a Kj target to hit, the theory being that if I rode at 80% power I would hit said target in 20 mins dead, obviously finish quicker by going faster/harder.)
My best result was just over 18 1/2 mins at an average of 343 watts: I extrapolated (blind guessed!) that downwards to 335 watts for 20 mins which at a weight of 69.4 kilos gives a 20 min w/kg of 4.82 and a 60 min w/kg of 4.47 (I've taken 7.5% off the 20 min figure).
Now, I've always thought that I've got a fairly decent engine but this is the first time I've got to test it in a lab, and I can't quite believe the results against, for example, Coggan's power chart. I mean, I do a 4-5hr ride every six weeks or so, a few 2-3hr hilly / interval rides a month and I commute to work 7-10 miles each way fortnightly. Have done a few evening 10s with a best time of 23.55 on a pretty flat course (A10/11) and I want to take a chunk off that next summer.
Two questions:
1) have I done my sums right, because I just don't see myself as being in that sort of place on the Coggan chart;
2) if said sums are right, then what would be a sensible (yet stretch) target for lowering my 10 time? One minute off? Two? (I know there are other variables to consider!)
Thanks for your time
Im pretty shocked if your pb is only that if you can pump out those figures. I did a 23.30 on a road bike without aero bits before I had a PM. I cant imagine I was stronger back then and my FTP is only 270 at 70kg.
I agree.. sounds like you have age on your side..most of the young 'uns do their club 10s .. not flat but false flat almost throughout... but when weather is clement,, decent times start at 21 and below.
someone has a bit of work to do on their cycling.. (the bit about turning the pedals) and worrywitter less about FTP and the like.0 -
Thank you everyone for your contributions, especially Alex for the comprehensive reply. I won't pretend to understand all the science but totally get the aero piece. A bit more context to flesh out some of the bones...
I'm 43 next May - don't know if that counts as having age on my side - and have been riding relatively consistently since 2010. Approx 2.5k miles pa for three years then 3.2k in 2013, 4.2k last year and 5.8k ytd. Work continental shifts alternating days / nights, have a young family & virtually all my riding is solo with time / intensity as per my first post. Have never done any specific structured training because I've never had a specific goal. TT-wise did two in 2012, one in 2014 and one last year - the 23.55 on a self-built bike (cheap Ridley Cheetah frame from CRC) that I just jumped on and rode so there's 100% scope for improvement fit-wise. Basically I'm just curious as to whether those lab results confirm that I've got a half-decent engine and how much more I could squeeze out of it with specific TT training (and Alex has already answered my suspicions about aerodynamics / bike fit, thanks again).
Apologies for the worrywittering...
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I would say you have a decent engine, on my local 10 TT my pb is 21:36 with 300W at 64kgs, not a overly fast course with the course record being 19:50 something from someone at 63kg with 400W. With your power if you could get aero enough a good course on a good day you could do a sub 20 but getting aero and maintaining power is easier said than done0
