Introducing PowerCal a new kind of Power Meter

[BicyclePower]

then I take one for sure, will you post when they are in stores and which have them or will it be online sales?

 

for the moment we are unsure how or if they will be sold through stores as historically PowerTap product requires allot of aftersale support and so Bicycle Power Trading have prefered to sell direct, this also helped keep costing down, however we are running it by one or two of the shops at the moment. however you can order from us @ www.bicyclepower.co.za

 

i will let everyone know when we will be getting them in.

[NotSoBigBen]

for the moment we are unsure how or if they will be sold through stores as historically PowerTap product requires allot of aftersale support and so Bicycle Power Trading have prefered to sell direct, this also helped keep costing down, however we are running it by one or two of the shops at the moment. however you can order from us @ www.bicyclepower.co.za

 

i will let everyone know when we will be getting them in.

 

Cool, quite happy to order direct

[BicyclePower]

Anticipated FAQ’s & Responses

1. How is it any different (why is it better) than HR?

a. First, it introduces the relationship of a dose vs. training.

b. The PowerCal contains an algorithm that is sensitive to acute changes in HR and can account for rapid changes in power output.

c. It translates conversations into the vernacular of power training: watts, kilojoules, peak power, FTP, etc.

d. Current power meter users can now have uninterrupted training load data for activities where power meter data may be unavailable, like commuting or MTB riding.

2. Why does it no longer have to be calibrated?

a. After years of research and reevaluation of the algorithm it was determined that the calibration process added no more accuracy than the algorithm alone. Due to the variability of heart rate, both between and among individuals, calibration did not statistically increase accuracy of translated energy expenditure. Some individuals may see improved accuracy through calibration but, as a whole, the results show the algorithm alone is able to translate heart rate to power as well as individual calibration.

3. How accurate is it?

a. This is not as accurate as a PowerTap and not intended to replace one. Research has shown varying degrees of accuracy based on individuals and types of riding. Accuracy will depend greatly on the individual and type of riding.

4. How does it compare to PowerTap?

a. It doesn’t and isn’t intended to. The PowerTap directly measures power through strain gauges on the torque tube, which is a direct measurement of power. PowerCal is an estimated value derived from HR.

5. How, after all these years of saying HR alone is not the best measurement for training, can you now measure power from HR?

a. There has always been a correlation between HR and power, it’s just that it varies depending on conditions. We’ve simply designed algorithms which predict power based on HR.

6. Will PowerCal give you both HR and power readings?

a. Yes.

7. How does it estimate KJ’s burned: from HR or from estimated power?

a. Power.

8. How does it accommodate changes in fitness, fatigue, dehydration, etc. (all the things which influence HR)?

a. In terms of changing fitness with a given individual our initial assumption was that yes, as fitness increased the user would need to re-calibrate to properly adjust the system but what the research shows is that these changes are relatively very small compared to other factors at play when using heart rate as the base measurement. In other words, the margin of error when using heart rate as the sole measure of exercise intensity is too great to accurately represent changes in fitness. However it needs to be mentioned if fitness is at a relatively advance stage it would be suggest going the route of PowerTap

b. In discussions of PowerCal as it relates to fitness, fatigue, dehydration, etc. one can look at the power output relative to other metrics such as speed over the same course or changes in cadence over time. Power output as a performance metric is almost always spoken of in terms of how it relates to the other variables to gain insight to the individual’s progress.

9. Is it more accurate for certain types of riding (steady-state intervals, climbing, sprinting, etc.)?

a. PowerCal is more predictable in a steady-state, longer intervals or climbing where constant fluctuations in output are minimized

[Pieterg]

Dave put my name on the waiting list,Now be patient and try to wait for my "PoweCal",well I wanted to buy a power meter for 6years($$$$$$$ is the problem) but this will do just fine

[BicyclePower]

Dave put my name on the waiting list,Now be patient and try to wait for my "PoweCal",well I wanted to buy a power meter for 6years($$$$$$$ is the problem) but this will do just fine

 

 

your name is right at the very top.

[Pieterg]

Yippie I'm first,eat your heart out,sorry but i'm over the moon :drool:

Edited June 28, 2012 by Pieterg

[LOOK695]

Sounds very interesting. You say it is not as accurate as your PowerTap, do you know percentage wise what the difference is about? Also it is mentioned as you get stronger and fitter that the PowerTap would be better. Why? Lastley on the pic of the HR strap there is a box on the left of the pic. What is that and is it strapped on your body?

[BicyclePower]

Sounds very interesting. You say it is not as accurate as your PowerTap, do you know percentage wise what the difference is about? Also it is mentioned as you get stronger and fitter that the PowerTap would be better. Why? Lastley on the pic of the HR strap there is a box on the left of the pic. What is that and is it strapped on your body?

 

 

I have not had any information from the States as to the accuracy of the system as yet however it does depend allot of the person. as you get stronger and more into training with Power it is obvious that training with Power is beneficial for you then in order to keep this advance going it would then be suggest to move over to a PowerTap system as the accuracy is allot higher. to improve by 10-20 for an entry level cyclist within a season is possible however at elite level to improve 5-10% in a year is considered a huge improvement thus to keep the improving trend going one should look at upgrading their training system.

 

I have now updated the pic, the previous pic was of the original powercal that required calibration and there was an ANT+ calibration stick included this has now been done away.

[BicyclePower]

Guys please try look at the powercal from this point of view, if you want PowerTap accuracy of +/- 1.5% then spend the R8000+ and buy a PowerTap however if you want a way to track fitness with another metric or are interested in Power Outputs then the PowerCal falls into this bracket at +/- R1000

[Robrider]

Sho, I won't lie if I said I was a bit sceptical. HR is a measure of input and Power a measure of output. That relationship determines how fit you are, no?

 

Also, please explain this senario... Robbie Hunter and I are sitting doing steady state at the same HR. Obviously he would be working harder that me. How does it know the watts? Surely there must be some kind of calibration

[Eldron]

I think it's important to realise that the actual power will not be accurate (accurate is of course a relative term) - anything based on formula is wide open to human standard deviation.

 

The value of this tool lies in the change of numbers not the actual numbers - ie: as you improve your power numbers will improve.

 

Much like Polar's Fitness Number, Calories used etc - it's a number to monitor improvement - the actual number is not important.

[Pieterg]

So True

[Robrider]

I think it's important to realise that the actual power will not be accurate (accurate is of course a relative term) - anything based on formula is wide open to human standard deviation. The value of this tool lies in the change of numbers not the actual numbers - ie: as you improve your power numbers will improve. Much like Polar's Fitness Number, Calories used etc - it's a number to monitor improvement - the actual number is not important.

 

Fair enough. But I'm just trying to understand. If you improve, you will push a higher Watt at the same Heart rate, all other things equal. So how does it know your watts have gone up over time, if your HR is the same? There must be some other metric it uses.

[LOOK695]

I have not had any information from the States as to the accuracy of the system as yet however it does depend allot of the person. as you get stronger and more into training with Power it is obvious that training with Power is beneficial for you then in order to keep this advance going it would then be suggest to move over to a PowerTap system as the accuracy is allot higher. to improve by 10-20 for an entry level cyclist within a season is possible however at elite level to improve 5-10% in a year is considered a huge improvement thus to keep the improving trend going one should look at upgrading their training system.

 

I have now updated the pic, the previous pic was of the original powercal that required calibration and there was an ANT+ calibration stick included this has now been done away.

Thanks. I understand what you are saying, but Eldron has also a strong argument in that it is about your no's and consistency over a period of time. So the PowerCal should also show a % increase compared to the PowerTap in your power figures

[Andrew_ew]

Not trying to be a smartass here but just genuinely trying to understand how this works:

 

It sounds like it is a heart rate monitor strap with a processor that runs an algorithm from which it derives data that is then broadcast on ant+ - is this correct?

 

Would it also be correct that this algorithm could be run on any data set provided by the output of any heart rate monitor when it is being worn. i.e. if one had the algorithm then one could run it on the raw data provided by a standard heart rate monitor so in essence it is the algorithm wherein the value lies and as such would not be published for external verification?

[Eldron]

Fair enough. But I'm just trying to understand. If you improve, you will push a higher Watt at the same Heart rate, all other things equal. So how does it know your watts have gone up over time, if your HR is the same? There must be some other metric it uses.

 

I have no idea

 

My guess is that is will have to be paired with a GPS based device - that way when you input your weight it will calcuate power based on things like acceleration/hill climbing etc. Without acceleration/hill climbing the calcs will be a stab in the dark in my opinion...