I have a really old mag trainer that probably isn't compatible with anything.

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maybe she's born with it, maybe it's chlorine
If you're injured and need some sympathy, PM me and I'm very happy to write back.
disclaimer: PhD not MD

If you go on their website, they have a list of trainers that the program is compatible with. THe list is on this page http://www.trainerroad.com/virtual-power. You can't do it without a speed and cadence sensor on your bike. You don't need to have any sort of computer such as a garmin forerunner or anything like that, instead, all of the data goes from the sensor to the usb stick to the program on the computer.

Which trainer? Sometimes the manufacturers publish the curves. Other times we've had people ride them with power meters to develop them.

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CEO at TrainerRoad
Co-host of the Ask a Cycling Coach Podcast

Hi Nate,

I am impressed; you may have it.


My trainer says "Minoura Mag 500." There's no /850LW .

I'll send you a PM...

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maybe she's born with it, maybe it's chlorine
If you're injured and need some sympathy, PM me and I'm very happy to write back.
disclaimer: PhD not MD

A little more detail on the calibration here http://www.youtube.com/watch?v=5RHw0YzOQZk Supposedly it will be at distributors 20Jan to ship.

From your comments, it sounds like it WOULD be better over a longer period of time - like pacing an IM. I am small and found that my power meter yielded very little help over what I would have from HR. I know that HR trails power, but I am also interested in the power cal. Will wait for more info from you.

Yes and no.

My concern with an IM pacing on it, is that your HR will slowly erode, especially the last 30-40 miles - meaning you may be impacting your HR to power ratio beyond what the test will predict.

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My tiny little slice of the internets: dcrainmaker.com

Are you sure? I think it actually would be very useful for people who use a power meter regularly because it should allow them to correlate cross training workouts to their bike workouts.

For example, my PowerTap is laced to a carbon aero hoop. I'm not using it on the road now that the pavement in the northeast is cratered from freeze-thaw. Rather than buy another PowerTap training wheel, I'm thinking I can use the PowerCal to easily gauge my winter rides against my summer rides (+/- 5% which is fine for this purpose). Or when it snows and I go X/C skiing instead of riding, I can use the power conversion to pace myself to simulate a bike workout. And if I decide to take a spin class with my friends, rather than a spin in the freezing cold, I can still ride with power feedback. But I would still have my PowerTap on the trainer at home for cross-checking the calibration.

Naturally it is going to be useless for pacing rapid intervals--at best it will tell you what you did wrong on the last one. And it's not going to be good for pacing deep into an endurance event because of heart rate drift. Plus it's rather pricey for a heart rate strap with a programmable calibration table. But we're paying for the development and the convenience of being able to get power equivalent where we don't have access to a power meter. Now that I have been using a PowerTap for training and pacing, I've calibrated my thinking in Watts. So I think the PowerCal would let me expand this framework beyond the bike.

Has anyone had a chance to try any of these applications on the PowerCal yet?

Those are indeed valid secondary uses - and one of the reasons I think it's a cool product. But, I would say that for many on ST, as a primary product (first power meter), I think most will align with a direct force power meter (DFPM), like you have.

Enjoy!

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My tiny little slice of the internets: dcrainmaker.com

Just like the original poster, I've been looking for a powermeter, just happened upon the powercal product and done what little reading is available.

The issue I would see being a problem is the need to re-calibrate every 4-8 weeks, meaning regular access to a Joule computer!.

That aside, can't seem to find if the product has actually been released yet, regular searching doesn't bring up any suppliers.

Anyone know where I can check one out?

TIA

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Glen

That is not accurate information, although that was what I had been told by Saris/Cycleops. The fact is they dumbed down the product. Cut the price in half, $139.99 for the deluxe model. And turned out an absolute worthless piece of junk!!! I have 4 Powertap wheels and 2 Computrainers so I am very accustom to training with power. I wanted the PowerCal for CX and Mtb. Absolutely pure junk! The power/watt readings I get are typically 100 to 150 watts BELOW the effort! And it is not real time; it is an average. I have been coasting at 450 watts and then, while doing an effort, be riding at 40 watts!
Do not waste your money! I am trying to return this junk!

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Russell DeBarbieris

Apparently not necessary now. It's inherent (in)accuracy is not bettered by regular calibration;

Quote:

Why does it no longer have to be calibrated?
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.

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Trust me I’m a doctor!
Well, I have a PhD :-)

I'm playing with it and will do a full post later. Short version is you can't use it to manage an active workout (intervals) but it seems like it might be useful to track summary power and fitness over time.

Good for things like when you are on a borrowed bike, can't afford a real power meter, or maybe even spinning/crappy hotel gym bikes.

Does anyone know if this algorithm is similar to what Strava uses to determine power?

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No, it is not. Strava uses grade & speed to gauge power... on flats Strava's power estimate can be extremely inaccurate due to wind speed.

This device uses heart rate variation (the change in heart rate, rate and magnitude) to determine power.

What I don't get:

if there is not calibration anymore, how can it have any idea of your basic zone ?

I red all the Faq and nothing about it (http://www.cycleops.com/...qs/powercal-faq.html)

for example: Lance is probably @200W when cursing @100bpm, on my side I will be more @100w for the same HR...

So how can it be accurate at all ? Ok if you were coupling it with GPS data and Speed it may have a better idea (as for Strava), but with only HR I don't get it...

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Head coach and owner at BartCoaching.com

This was our initial concern as well and why we assumed a calibration would be needed.

However, in testing that assumption in the lab it was pretty clear the calibration did not provide a significant improvement across our intended customer base.


We concede the product won't work for Lance. We've set it up for a reasonably fit athlete knowing that the established issues with using heart rate to determine energy expenditure are bigger limiters for PowerCal than the absolute power to heart rate relationship of a given individual relative to another.


Hope this helps-

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Jesse Bartholomew

Thanks for your answer Jesse, I was referring as Armstrong as an extreme to emphases on my argument, but the same can be apply between an average Age Grouper and an AG qualifying for Kona. (or even easier: between boys and girls)


Here is a screenshot from my first test...

Using a PowerTap, with the yellow computer, and the PowerCal with my Garmin 910XT.

I've been out for a recovery ride.

I took several Split while cursing.

Here is a comparison from the same split (ignore de start time, as I started the YellowComputer later)

On the left is the PowerCal value, on the Right is the PowerTap.


You will notice a huge difference between the two value.

Ok, we know there is no more calibration, so I can still live with the idea that there is an offset that I need to add between my real Power and the PowerCal value.

Next step: I will be testing on Treshold Intervals, to see if there is an offset or any logical relation that make this tool more useful than just a cardio belt.

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Head coach and owner at BartCoaching.com

Is your "cruising" heart rate really < 125bpm? That's really low and outside the normal range assumed in the PowerCal algorithm, which roughly speaking would assume a bpm of 140 to 150 for an all day type pace.

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Jesse Bartholomew

140-150 will be more my HIM pace, between 145 and 160 I will be around FTP -10 to 20mn intervals-, around 325w.

I'm quite sure any good AG will be below 120 bpm when cruising. (my easy ride are around 100bpm)

But I will test it during Tempon and FTP session, were Power information is more useful than when cruising.

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Head coach and owner at BartCoaching.com

Jesse, I sent you a PM.

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Head coach and owner at BartCoaching.com

Bump.

Any updates or more recent opinions on this?

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VDOT O2 Run Coaching
Team INFINIT Discount Code: RowanJones

This is why I never bought one of these. My threshold is around 310 watts, maybe a little more when I'm really fit. In any case, I think this watch is calibrated for the less serious bike rider that has a threshold closer to 220. Which means the watts would read low if I were to use it.

Had they added even a simple calibration screen that asked what your threshold power was, I think that would have helped.

I use it and tested it against what the compu trainer WATTS numbers where giving me and I was a good 25% BUT when you look at HR and WATTS it balances things out.

I still would like to add an *actual* power meter, but for $99 I bit. I just got it today and paired it up since I'll use it for HRM during my afternoon run. I did notice that there was a "Calibrate" in the PM menu on my 910XT. Is there anything to that or is it just a default drop down in the menu? I have a 1:30 trainer spin in the morning so I'll be interested to see what sort of numbers it comes up with (I have no idea about my FTP, etc. because I have never worked with power/a power calculator). So the 20 minute test is sort of the standard way to go to determine FTP?

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VDOT O2 Run Coaching
Team INFINIT Discount Code: RowanJones