Introducing PowerCal a new kind of Power Meter

[Jeepdude]

Jeepdude - how did the beta blocker impact your power output readings on Powercal? Assuming your heart rate is 25 odd bpm lower than normal, was the power output consistently lower than your output before you took the betablocker? Or did it fluctuate wildly, which would indeed render the Powercal useless.

 

I ask as I am in the same boat.

POWER was just WAAAAAYYYYYY down , i guess you can carry on with the lower numbers , but you dont have a true reflection on power numbers. i do suggest going off the beta blocker and finding an alternative. i was using the beta blocker during preparation for the double century and it had a very undesirable affect.. i did hours of riding but lost speed and ability to rev the engine so to speak...

[NotSoBigBen]

Does the 'absolute' number matter or is it how you use/interpret that number?

[Dr Snuggles]

Does the 'absolute' number matter or is it how you use/interpret that number?

 

if the outputs are inaccurate, but stable, then the relative change between those values are of more importance than the actual number itself. Plotted over a period of time, it will give you a fairly good indication of changes in your performance. but if the instantaneous value is inaccurate, and if there are large variations in output under the same conditions, then it's practically useless tbh. But I dont think the latter is the case with this type of powermeter simply because the algorithms that determine power from the one parameter it picks up is constant. That parameter being your HR.

So I would suggest you look at relative changes in power readings over a period of time to determine your level of performance.

[Blackadder]

 

 

if the outputs are inaccurate, but stable, then the relative change between those values are of more importance than the actual number itself. Plotted over a period of time, it will give you a fairly good indication of changes in your performance. but if the instantaneous value is inaccurate, and if there are large variations in output under the same conditions, then it's practically useless tbh. But I dont think the latter is the case with this type of powermeter simply because the algorithms that determine power from the one parameter it picks up is constant. That parameter being your HR.

So I would suggest you look at relative changes in power readings over a period of time to determine your level of performance.

 

That is my understanding. What I would like to know is what the impact of a beta blocker that lowers hr has on the algorithm that calculates power with PowerCal. If PowerCal measures changes in hr rather than absolute hr, then the impact of a beta blocker on hr should be minimal. However, whilst I get stable and predictable power readings, like Jeepdude above, I find my power readings are rather low. Perhaps it's just my poor performance and I am looking for excuses????

[Dr Snuggles]

That is my understanding. What I would like to know is what the impact of a beta blocker that lowers hr has on the algorithm that calculates power with PowerCal. If PowerCal measures changes in hr rather than absolute hr, then the impact of a beta blocker on hr should be minimal. However, whilst I get stable and predictable power readings, like Jeepdude above, I find my power readings are rather low. Perhaps it's just my poor performance and I am looking for excuses

 

If one looks at what beta-blockers actually do, and i quote from wikipedia:

 

Beta blockers target the beta receptor. Beta receptors are found on cells of the heart muscles, smooth muscles, airways, arteries, kidneys, and other tissues that are part of the sympathetic nervous system and lead to stress responses, especially when they are stimulated by epinephrine (adrenaline). Beta blockers interfere with the binding to the receptor of epinephrine and other stress hormones, and weaken the effects of stress hormones.

 

IMO:

Training is physical stress, and is reacted upon as a normal stress response by your body, and therefore, you are going to underperform according to PowerCal at the same level of exertion. If you dosage is constant, then like with inaccuracies, the relative difference between performances at the same level of exertion under the same dosage will be what's important. Absolute values are skewed because of the effect of the beta-blockers. But one must keep in mind that when under the influence of any drug, there is a peak period followed by a taper as the drug follows its degrading impact curve. One could use drug-half life as an interval during which one assumes constant impact. In reality, it tapers off as the renal system filters it out of the blood stream, and even that varies due to changes in physiology brought about by physical activity. But i'd make an assumptions of constant dose over an interval based on drug half life.

 

Knowing these periods of constant dose, one can then make better assessments of PowerCal data on a relative basis. Absolute values should be discarded IMO.

[raptor]

Were can i buy a powercal? Waiting 3 days already to hear from bicyclepower

[NISI]

Were can i buy a powercal? Waiting 3 days already to hear from bicyclepower

Maybe they only open Monday after the festive season-only good service from them.I waited 3 days to reciev my powercal

[Wallee]

Were can i buy a powercal? Waiting 3 days already to hear from bicyclepower

 

Have you tried online? www.bicyclepower.co.za

[BicyclePower]

Were can i buy a powercal? Waiting 3 days already to hear from bicyclepower

 

sorry to hear you have been waiting so long, to the best of my knowledge we have responded to all queries via e mail.

 

drop an e mail to dave(at)bicyclepower.co.za

[Jaco-fiets]

Just some feedback from my side. After using the powerbeam last few weeks I have made some notes on the powercal readings compared to the powerbeam in certain hr ranges.

 

From what I can see so far is that the higher the intensity of your ride the more accurate the avg reading of the powercal is. Anything from 130bpm avg and lower the watts seem to be out by sometimes up to 15%. For rides higher than a 140bpm avg the accuracy seems to be from about 7% to sometimes as close as 0.5%. The higher the avg hr the more accurate the avg watt. The powercal always gives lower avg watt readings

 

Do any of you notice something simular?

Edited June 29, 2014 by Jaco-fiets

[NISI]

My powercal compared to the powerbeam is 25% lower,think it could be with the bloodpressure meds I am taking