It's killing me but..........

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even when my cadence remains steady and with me in the same gear, I am seeing the power go up and down by about 30-40 watts.But these fluctuations will be irrelevant over time. It's no problem to have the common sawtooth pattern of watts. It's only when watts remains above or below your target for more than a few seconds.

you mentioned smoothing - I have my data recording set at 1-second - are you referring to smoothing on the cpu display itself though???You can set up your PT computer to average current watts (rolling average). Note that this is different from average watts (average of watts from the beginning of the ride). When people refer to smoothing, they mean this rolling average function. With the PT SL, this function is found at Setup 2. You can experiment with this setting. It will have the effect of damping, or smoothing, the current watts display.

Hey RD - another set of 2 x 20's are in the books - so now I can respond http://cyclingforums.com/images/smilies/biggrin.gifCool.:cool: That's what it's all about.

But these fluctuations will be irrelevant over time. It's no problem to have the common sawtooth pattern of watts. It's only when watts remains above or below your target for more than a few seconds.Ah ok - I think I am seeing what you mean and it makes sense - ie....momentarily being 20 watts below or above is fine, key word momentarily~! http://cyclingforums.com/images/smilies/cool.gif

You can set up your PT computer to average current watts (rolling average). Note that this is different from average watts (average of watts from the beginning of the ride). When people refer to smoothing, they mean this rolling average function. With the PT SL, this function is found at Setup 2. You can experiment with this setting. It will have the effect of damping, or smoothing, the current watts display.Yes I understand what you are saying here....average watts is a measure for the entire ride, whereas average current watts would be what the time range for what you are seeing on the display...ie....1 second vs. a 3 or 5 second rolling average of current watts....

So you know, even when my cadence remains steady and with me in the same gear, I am seeing the power go up and down by about 30-40 watts.
Maybe it has more to do with the powertap as a tool itself, more than your own ability to ride constant power.

"Since the computer records at 1.26-second time intervals, the power reading may fluctuate up to 40 watts (20 watts above and below the true wattage level) from second to second. Though it is possible for such fluctuations to reflect actual changes in power output, when this occurs with the PowerTap it is more likely to be the computer that is creating the problem." (Allen & Coggan, "Training and racing with a power meter" 2006)

I too get those fluctuations. They do not reflect my ability to apply power evenly. When working out on a trainer, I always set the Display avg to 30s to smooth things up.

Maybe it has more to do with the powertap as a tool itself, more than your own ability to ride constant power.

"Since the computer records at 1.26-second time intervals, the power reading may fluctuate up to 40 watts (20 watts above and below the true wattage level) from second to second. Though it is possible for such fluctuations to reflect actual changes in power output, when this occurs with the PowerTap it is more likely to be the computer that is creating the problem." (Allen & Coggan, "Training and racing with a power meter" 2006)

I too get those fluctuations. They do not reflect my ability to apply power evenly. When working out on a trainer, I always set the Display avg to 30s to smooth things up.Thanks for your input :)

A few folks, frenchy and Alex among others, have mentioned the 1.26 time second interval as you did. Obviously that will affect the 'smoothness', if you will, of the numbers, even if as you said, the work you are doing is relatively constant.

After pondering this for a bit, I think that increasing the time interval, like you do on the trainer, for the current wattage makes sense. It is distracting, at least for me, to see the display change change so much when I feel I'm doing a fairly steady effort - invariably when I see it momentarily drop 20 watts, i'm apt to push, then of course you get too high - it is a vicious cycle and a distraction too!

Cool.:cool: That's what it's all about.Yes and I put the blame squarely on you, with, well, Tyson as an accomplice!

Training weeks are just another way of saying L4's...:D

Yes and I put the blame squarely on you, with, well, Tyson as an accomplice!And I, in turn, lay it off on Dr. Coggan.

It is distracting, at least for me, to see the display change change so much when I feel I'm doing a fairly steady effort - invariably when I see it momentarily drop 20 watts, i'm apt to push, then of course you get too high - it is a vicious cycle and a distraction too!The fluctuations simply reflect the sensitivity of the measurement of power. The measurement technology is incredibly sensitive to both torque and cadence. If you have it set to the shortest duration (1.26secs) and press a little harder on the downstroke a couple of times, you will see watts jump in response. By contrast, the other variables we are used to managing (speed, cadence, HR) change at glacial speed. Personally, I like to see my power data "raw" with no smoothing, but many are distracted by the jumpiness of the variable and prefer to dampen it quite a bit. The main difference is when you intentionally want to go from, say, 180W to 200W. It will take a little longer to settle in on the new target with smoothing.

The fluctuations simply reflect the sensitivity of the measurement of power. The measurement technology is incredibly sensitive to both torque and cadence. If you have it set to the shortest duration (1.26secs) and press a little harder on the downstroke a couple of times, you will see watts jump in response. By contrast, the other variables we are used to managing (speed, cadence, HR) change at glacial speed. Personally, I like to see my power data "raw" with no smoothing, but many are distracted by the jumpiness of the variable and prefer to dampen it quite a bit. The main difference is when you intentionally want to go from, say, 180W to 200W. It will take a little longer to settle in on the new target with smoothing.Indeed, the word you used, glacial, or I might say vague, seems to best describe those other things we go by - HR, speed, cadence, etc - vs. power which changes at the blink of an eye.

I'm going to experiment with increasing the time period for the current watts display - see how I like it as compared to the way I've been using.

So after 2 x 20 on the trainer and a lunch break, I went for a nice 1.5 hour L2 ride. Mainly to stay fit, trim, maintain endurance, oh and to ride outdoors for the first time in a week! Viva la diferencia!

Anyway, I had read a number of threads on sprinting and force, including the 'gyming for power', and the other well known ones including Dr. Coggan & Warren....so I decided to try some 10-15 second sprints. At first I was dubious, but remembered how in those threads, 39x15 sprints were a good starting point - no grinding out huge gears at slow cadence - plus a few other tips.

I came up with this, which shows yet again, that untrained folks (that would be me) can generate plenty of power. Too bad it is only for a second or two....:

http://i9.tinypic.com/2gt1dgp.jpg (http://i9.tinypic.com/440o5ki.jpg)

My power profile looks like the slope of say, K2 or mount everest, going down that is!

Anyway, I had read a number of threads on sprinting and force, including the 'gyming for power', and the other well known ones including Dr. Coggan & Warren....so I decided to try some 10-15 second sprints. At first I was dubious, but remembered how in those threads, 39x15 sprints were a good starting point - no grinding out huge gears at slow cadence - plus a few other tips.

I came up with this, which shows yet again, that untrained folks (that would be me) can generate plenty of power. Too bad it is only for a second or two....:



http://i9.tinypic.com/2gt1dgp.jpg (http://i9.tinypic.com/440o5ki.jpg)



You might want to make your way up to Colorado Springs. With that kind of max power you might be well suited to some track events. Andy Coggan can tell you better what your power profile is best suited to (once you have a power profile) because his wife is a champion track cyclist.

You might want to make your way up to Colorado Springs. With that kind of max power you might be well suited to some track events. Andy Coggan can tell you better what your power profile is best suited to (once you have a power profile) because his wife is a champion track cyclist.I vaguely remember him mentioning that in those threads I alluded to, about his wife being a champion track rider. Ironically, I have a lot of respect for those that compete and are successful at track riding but it doesn't really have a big appeal to me. Maybe I don't know enough about the sport or haven't given it a try. I just find sprints fun and a nice change from L4's, etc.

it is a vicious cycle and a distraction too!
That's the reason I posted what I did - so you would understand that it occurs because of the way the PT measures power and hopefully ignore it.

The fluctuations simply reflect the sensitivity of the measurement of power. The measurement technology is incredibly sensitive to both torque and cadence. If you have it set to the shortest duration (1.26secs) and press a little harder on the downstroke a couple of times, you will see watts jump in response.
No, actually they are an artifact of the way the PT specifically handles the torque measurement. They are absent on other PMs. Even if you apply the exact same force on every stroke, you will see the fluctuations as long as cadence is not a 95.2 rpm or some half-multiple of it (ie, .5, 1.0, 1.5, 2.0). OTOH, if you pedal at 95 rpm you will see just how consistent your pedal strokes are.

Personally, I use a 3-sec display averaging (smoothing).

http://i9.tinypic.com/2gt1dgp.jpg (http://i9.tinypic.com/440o5ki.jpg)
LOL! Count her in the club (http://www.cyclingforums.com/t352414.html)! :D

Lucy, didn't you say you were ~73kg? If that's a 'good' value (ie, not one of the spurious bogus figures that shows up from time to time), then that puts you at the top of the world-class women in the country. Check to see that that figure is right, then start shopping for contracts and endorsements. :)

LOL! Count her in the club (http://www.cyclingforums.com/t352414.html)! :D

Lucy, didn't you say you were ~73kg? If that's a 'good' value (ie, not one of the spurious bogus figures that shows up from time to time), then that puts you at the top of the world-class women in the country. Check to see that that figure is right, then start shopping for contracts and endorsements. :)LOL @ club...and yes, I did post in that thread http://cyclingforums.com/images/smilies/biggrin.gif

I think it is a good value, looking at the power file I can see the entire 10 second peak for the sprint. I see similar ones, for the ones I did afterwards, but with less wattage (around the 900-1100 range - when I tried sprinting with a bigger gear rather than a nice small one like 39-15). According to the chart that's pretty good, but like I said, track racing doesn't really interest me. I'd trade whatever that 1second w/kg number is (like 19.5) for even just a mere 3w/kg for FTP http://cyclingforums.com/images/smilies/rolleyes.gif

I came up with this, which shows yet again, that untrained folks (that would be me) can generate plenty of power. Too bad it is only for a second or two....:

http://i9.tinypic.com/2gt1dgp.jpg (http://i9.tinypic.com/440o5ki.jpg)

My power profile looks like the slope of say, K2 or mount everest, going down that is!


No wonder now why you're not talking shopping and troubled relationships on woman's sports forums :) (with the other 99%)

(was this politically correct?)

No wonder now why you're not talking shopping and troubled relationships on woman's sports forums :) (with the other 99%)

(was this politically correct?)LOL - I don't know if it was politically correct, but I hear you. I tried some of those ladies sports forums and found them a bit wishy-washy for my taste.

Relationships? Just with my bike and PM thanks :D

Shopping? Absolutely, I go shopping....just last week I walked out of the mall with a 5 kg tub of protein powder ;)

I just find sprints fun and a nice change from L4's, etc.Well, if you can get your FTP and AWC up high enough to be with the lead group for the sprint finish, you'll have them looking over their shoulder to find out where you are.:D

LOL @ club...and yes, I did post in that thread http://cyclingforums.com/images/smilies/biggrin.gif
Sweet! I want to see the reactions.:D 1400w is higher than probably 80% of the men on these forums are capable of (including me).

I think it is a good value, looking at the power file I can see the entire 10 second peak for the sprint. I see similar ones, for the ones I did afterwards, but with less wattage (around the 900-1100 range - when I tried sprinting with a bigger gear rather than a nice small one like 39-15).
39x15? :eek: According to the KK chart (http://kurtkinetic.com/pdfs/Power_Curves419.pdf), 1400w is about 40mph on the Road Machine. In a 39x15 that puts you at a cadence of 188. Sound about right?

Well, if you can get your FTP and AWC up high enough to be with the lead group for the sprint finish, you'll have them looking over their shoulder to find out where you are.:DAh, see now that sounds brilliant! I can only hope... :)

As for getting FTP & AWC high enough, well I've followed your advice so let's see what happens given enough time.

Question: I know that working at lower zones L1-L6, involves varying amounts of converting typeIIb to typeIIa fibers - will this negatively affect my ability to sprint? I'm thinking that regular L7 work would benefit me, and it wouldn't interfere with my L4 program.

Sweet! I want to see the reactions.:D 1400w is higher than probably 80% of the men on these forums are capable of (including me). Oh given that 80% number you gave me I imagine the skepticism will be high and belief rather low. Not that I would expect anything else!

I haven't forgotten how this one woman posted in the 'what's your FTP thread', something like 315+ watts and over 4 W/kg....then it turned out it was on a generic exercise bike ;)


39x15? :eek: According to the KK chart (http://kurtkinetic.com/pdfs/Power_Curves419.pdf), 1400w is about 40mph on the Road Machine. In a 39x15 that puts you at a cadence of 188. Sound about right?I can't say for the KK chart, because I did these on the road! Used a 39x15 on a slight (about 1-2%) incline, buitl up power then jumped and went as hard as I could.

EDIT: now that I think about it, the KK chart assumes about a 1% incline so I imagine it would be similar on the trainer, but I don't feel comfortable sprinting on it. Also, I didn't just go out and sprint on a whim, I had read a lot of articles on technique, gearing, etc so that helped a lot. My instinct was to use a big gear, but I did best with a smaller one as the threads here suggested.