All watts all the time

[PaulS]

Paul Smith is crapflooding again. Please ban him from the forum.

Thanks for proving my point about you, John.

Yes, please ban me from the forum.... But make sure to ban those that impersonate others using the quote feature at the same time.

Perhaps a poll is in order, Tyn likes that sort of thing.

_ PaulS should leave the forum.
_ John Rupp should leave the forum.

Let the community decide.

[johnlvs2run]

Yes, please ban me from the forum

Please please hurry and ban him.... before he changes his mind again.

[TomR]

PaulS--

You've been doing a good job ignoring John. Please don't start bickering w/ him again. It's utterly pointless.

It would be great if others would also ignore John's nonsense and stop blighting the forum.

Tom

[LateinEarlyOut]

Here is a thought.

rowing at 100 watts equals a 2:31.8 split

rowing at 200 watts equals a 2:00.5 split

rowing at 300 watts euals a 1:45.3 split

Now if you told me how many watts you averaged over 2k, would that tell me how fast you did the piece...well in fact no. Here is why.

Lets say I am going to row for 1000 meters. I will row it two ways but both will average 200 watts of power.

Pull all strokes of the 1k at 200 watts, which gives me a time of 4:01, with average watts of 200.

Pull the first 500 meters at 100 watts and the second 500 meters at 300 watts. I averaged 200 watts for the whole piece but it took me 4:17.1. This is the reason that even pacing takes less energy for the same speed than uneven pacing.

[PaulS]

PaulS--

You've been doing a good job ignoring John. Please don't start bickering w/ him again. It's utterly pointless.

It would be great if others would also ignore John's nonsense and stop blighting the forum.

Tom

I was not bickering with John, I was addressing Fred and John butted in with more of his usual insanity, which I pointed out quite nicely as being similar to other issues in his past, not mine. Then he decided to become the usual pit yorkie, I can't really help that. Others addressed the inanity of his other rantings, so no need for me to do it, and they were not harmful so I would not have done it anyway.

[haboustak]

Pull all strokes of the 1k at 200 watts, which gives me a time of 4:01, with average watts of 200.

Pull the first 500 meters at 100 watts and the second 500 meters at 300 watts.

I don't think you can "average" Power like that. Power is Joules/sec, so you have to take into account the duration over which the Power was applied. Hopefully, after your 1000m @ 4:37.1 the monitor would display 181.91 average Watts.

100 W * 151.8s = 15,180 J for 1st split
300 W * 105.3s = 31,590 J for 2nd split

46,770 Joules over 257.1 seconds is 181.91 Watts. Slightly less than the 200 Watt average of your other piece. That's what caused the difference in Pace.

Mike

[johnlvs2run]

Paul wasn't bickering.

That was his usual crapflooding of the forum and the way he treats everyone.

Just ask his wife and kids. He treats them the same way.

Please ban Paul Smith and TomR for being nasty and not contributing anything useful.

Thank you.

[HardGainer]

The poster above is right, all the numbers shown on the PM2/3/4 are derived, including watts, so watts are no more legitimate than any other number.

Fred Dickie

I'd suggest that the watts are at least a bit more 'legitimate' than the pace. ...

Yes, in the sense that calculation of power from the fundamental quantites that the C2 measures involves fewer assumptions than does, for example, calculation of a pace. I have no problem in using power, pace or speed in comparing performances. Probably the only reason a (somewhat) arbitrary "pace" is derived from the power is to give people who may not feel quite so at ease with the notion of power something they are likely to be more familiar with measuring and comparing (viz. time and distance travelled). It's also quite "nice" to be able to use a quantity that corresponds, at least approximately, to the pace of OTW rowing.

Other than the "familiarity factor" mentioned above, there's absolutely no reason why we should not determine the results of indoor rowing races, relative ratings etc. using average power supplied to the handle by competitors rather than time to complete a given distance or distance completed in a given time. Historically I'm sure that distance and time have been the most common means of comparing performance in many sporting events such as running, swimming, rowing, cycling etc. etc. only because of the ease with which they can be measured or at least ranked. If The Lord had given us PM3s (or the equivalent in each type of sporting event) from Day 1, we might have been using average power in place of these quantities!

[PaulS]

The poster above is right, all the numbers shown on the PM2/3/4 are derived, including watts, so watts are no more legitimate than any other number.

Fred Dickie

I'd suggest that the watts are at least a bit more 'legitimate' than the pace. ...

Yes, in the sense that calculation of power from the fundamental quantites that the C2 measures involves fewer assumptions than does, for example, calculation of a pace. I have no problem in using power, pace or speed in comparing performances. Probably the only reason a (somewhat) arbitrary "pace" is derived from the power is to give people who may not feel quite so at ease with the notion of power something they are likely to be more familiar with measuring and comparing (viz. time and distance travelled). It's also quite "nice" to be able to use a quantity that corresponds, at least approximately, to the pace of OTW rowing.

Other than the "familiarity factor" mentioned above, there's absolutely no reason why we should not determine the results of indoor rowing races, relative ratings etc. using average power supplied to the handle by competitors rather than time to complete a given distance or distance completed in a given time. Historically I'm sure that distance and time have been the most common means of comparing performance in many sporting events such as running, swimming, rowing, cycling etc. etc. only because of the ease with which they can be measured or at least ranked. If The Lord had given us PM3s (or the equivalent in each type of sporting event) from Day 1, we might have been using average power in place of these quantities!

Not quite sure what "assumptions" are being made in the calculation of watts on the C2 or RP, other than that the usual physical laws apply.

I'm also not aware of any other competition that uses a machine measuring user power production to determine a winner, the sports you mention actually involve moving over a real distance rather than a virtual one. Anyone know of Treadmill or Cycle Ergometer competitions?

If it went to a pure power standard, what would be the winning criteria? It couldn't be Total Joules, as that would make the slower athetes take even longer to finish, that is if the standard were set by using what the fastest Ergers produce, or the fastest would simply get done even more quickly (Hmmm, that doesn't sound too bad), or maybe it could simply go to a flat time of 6 minutes and the most Joules wins (or highest avg Watts). The last one would be heaven for race organizers.

[ebolton]

Anyone know of Treadmill or Cycle Ergometer competitions?

Actually, yes. When I was racing bikes in college (1970's), our team ran roller races in the winter, as a training exersize. I'm pretty sure other clubs/teams did the same and still do, especially with the newer computerized trainers.

I took a look at the Racermate site, and it looks like they are picking up some of the Concept 2 strategy.
http://68.115.203.26/ranking.html

Ed

[johnlvs2run]

The RacerMate site is quite interesting. I had their original wind trainer in the 1970's. It didn't last very long. Then I got a different brand that lasted a long time. Obviously they have improved quite a bit since then.

Regarding the c2 fan cage, another thing you can do is turn the cover so the lever is on top. I have done this and the lever doesn't move at all, though the duct tape is still on there too.

[mcj22]

I'm not sure I buy the idea that watts are a better measure of how much "work" or "extra work" your body must do to reach a goal. True, they are a measure of output, but I think what you are speaking about is an idea of additional effort required. For instance, in moving from producing 10 to 20 watts I doubt your body works twice as hard - e.g. heart rate shows minimal change. In this vein, watts can be just as useless as split times in gauging extra effort required.

Essentially, I'm saying that effort to watts probably shows a nonlinear relationship just as effort to split time does. Having said this, I do think watts is a better way to guide training when deciding on appropriate pacing given knowledge of your max effort, particularly if you follow the aneorobic threshold training school of thought.

[michaelb]

For instance, in moving from producing 10 to 20 watts I doubt your body works twice as hard - e.g. heart rate shows minimal change.

Hmmm, this is interesting. I would think as a matter of physics that you would need to work "twice as hard" to generate twice as many watts. If there is some loss of energy in the system, you might have to work slightly more than twice as hard. But if that is wrong that would change a lot of my thinking about watts.

Is your point really about perceived exertion? So that the exertion to generate 10 watts vs. 20 watts is so low that I wouldn't perceive the difference? That is probably true. But my 5 year old daughter rowed at around 20 watts, and she would certainly notice the difference between 10 and 20, or 20 and 40 for example. I liked to think that I was 10x more powerful than my children based on the watts.

[HardGainer]

Not quite sure what "assumptions" are being made in the calculation of watts on the C2 or RP, other than that the usual physical laws apply.

I guess assumptions such as that the moment of inertia of the flywheel/fan assembly is constant and accurately known for each machine, that the method used to measure the time intervals by the sensor system introduces no significant error, the fact that error introduced by basing calculations of angular acceleration/decleration on averages over varying time intervals and applying digital methods to the subsequent calculations rather than being able to continuously measure instantaneous values and apply true differential and integral calculus methods to the calculation is insignificant, that the contribution to the actual moment of inertia made by dirt, dust, grease etc collecting on the flywheel assemby is insignificant, that temperature, pressure, humidity and other local environmental considerations play an insignificant part in modifyng the effective moment of inertia, that the "clock" frequency used in the electronics in the PM is sufficiently stable and accurate so as not to contribute significant error into the measurements being taken ... I'm sure if I could be bothered thinking about them there would be heaps more.

Sorry for the intellectual wanking here ... I resolved I wasn't gonna lower myself to the general tone of some of the posters on this forum ... it must be contagious

WRT your comment about sports not using power-measuring instruments on which to judge performance: Yes - this is an example of evidence of the point I was making about familiarity. Many (most?) sports are heavily reliant on instrumentation to measure quantities - time, distance, weight force for example. Apart from any inaccuracy inherent in the instrument itself, or inaccuracy introduced by the way in which the instrument is used, each of them relies on principles which may or may not be regarded as fundamental laws of physics. For example many scales used to measure weight rely on Hooke's law of extension which, at best, is a simple approximation based on the observed behaviour of SOME materials under CERTAIN conditions, but cannot be regarded as a fundamental law of physics. We also make assumptions about measurements performed without the help of instrumentation too: For example if we time someone running a circuit of a 400m track ... sure we make assumptions about the accuracy of the stop-watch, but also about the accuracy with which the track was laid out. This may have been done with a simple tape measure and a few sticks placed strategically in the ground! Why should we assume that a power-measuring instrument such as that on the C2 should be less relied on than these other instuments? I suggest the answer is that it is too much trouble for the average person to make the effort to research/analyse the relative accuracies of these various instruments and so they appeal to their instincts. Stop watches, tape measures and scales are familiar instruments, power-measuring instruments are not. We may then be tempted to make the unproven assumption that the power-measuring instrument is to be less trusted.

[PaulS]

Not quite sure what "assumptions" are being made in the calculation of watts on the C2 or RP, other than that the usual physical laws apply.

I guess assumptions such as that the moment of inertia of the flywheel/fan assembly is constant and accurately known for each machine, that the method used to measure the time intervals by the sensor system introduces no significant error, the fact that error introduced by basing calculations of angular acceleration/decleration on averages over varying time intervals and applying digital methods to the subsequent calculations rather than being able to continuously measure instantaneous values and apply true differential and integral calculus methods to the calculation is insignificant, that the contribution to the actual moment of inertia made by dirt, dust, grease etc collecting on the flywheel assemby is insignificant, that temperature, pressure, humidity and other local environmental considerations play an insignificant part in modifyng the effective moment of inertia, that the "clock" frequency used in the electronics in the PM is sufficiently stable and accurate so as not to contribute significant error into the measurements being taken ... I'm sure if I could be bothered thinking about them there would be heaps more.

Sorry for the intellectual wanking here ... I resolved I wasn't gonna lower myself to the general tone of some of the posters on this forum ... it must be contagious

WRT your comment about sports not using power-measuring instruments on which to judge performance: Yes - this is an example of evidence of the point I was making about familiarity. Many (most?) sports are heavily reliant on instrumentation to measure quantities - time, distance, weight force for example. Apart from any inaccuracy inherent in the instrument itself, or inaccuracy introduced by the way in which the instrument is used, each of them relies on principles which may or may not be regarded as fundamental laws of physics. For example many scales used to measure weight rely on Hooke's law of extension which, at best, is a simple approximation based on the observed behaviour of SOME materials under CERTAIN conditions, but cannot be regarded as a fundamental law of physics. We also make assumptions about measurements performed without the help of instrumentation too: For example if we time someone running a circuit of a 400m track ... sure we make assumptions about the accuracy of the stop-watch, but also about the accuracy with which the track was laid out. This may have been done with a simple tape measure and a few sticks placed strategically in the ground! Why should we assume that a power-measuring instrument such as that on the C2 should be less relied on than these other instuments? I suggest the answer is that it is too much trouble for the average person to make the effort to research/analyse the relative accuracies of these various instruments and so they appeal to their instincts. Stop watches, tape measures and scales are familiar instruments, power-measuring instruments are not. We may then be tempted to make the unproven assumption that the power-measuring instrument is to be less trusted.

No Problem with the "wanking", perhaps you should look at my web site and check out ErgMonitor, which has been verified in a lab for accuracy and precision WRT the Force units and found to be off by a near constant, the bungee tension, which implies that the laws of nature seem to be at work, and the tollerances of manufacture ar pretty good for equipment in good repair. Another interesting point is that although the flywheel moments of inertia vary by near a multiple of 5 between the Model A and the Models B, C, D; even if you tell ErgMonitor that you are using a Model A (much higher MOI), the paces displayed are so close as to be difficult to distinguish from using the correct MOI. The force figures are quite a bit off however, but that also invloves the very different length of the torque lever being applied to the axle. (different chain pitch and sprocket tooth counts).

With the introduction of Drag Factor, it was a very interesting change, and instead of being merely a revolution counter, which required particular protocol to be followed to maintain consistency (The Model A had to be set up so that there was 3 feet of clearance around the flywheel to allow full airflow), and though the watts could be calculated just as accurately for the Model A, if the clearance was not followed it would skew those calculations. This was taken care of with the intro of the PM1 and improved with the PM2 and so on. Now the DF is calculated for every stroke and applied to the next. Sure it's not perfect, but apparently it is, and has always been, good enough to provide what most consider an unbiased form of competition. It's still kind of nutty to all gather in a single venue to compete, when the machine is repeatable in any livingroom on the planet, but getting around nutty folks can be a lot of fun.

Hence this forum exists.