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Discussion Starter · #1 ·
After reading the Morris and Friel books I'm trying to get everything I'll need to start a more structured training regimen in the Fall/Winter. I'm good to go as far as a HR monitor and a trainer but I'm looking for a way to measure power now. A Power-Tap unit would be my first choice but it's pretty unrealistic for me being that I plan on staying married. ;) I've heard about the Polar S-720/725 with power unit also.
What are some other options to measure power accurately?

Thanks.
Lou.
 

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Hi Lou: Unfortunately, there aren't a lot of good instruments for measuring power that are cost less than a power tap. We did some work validating the Polar unit a couple of years ago using a bicycle mounted on a trainer. The results were pretty bad. We used 3 different units, did about 20 trials and the Polar was close only on a couple of them. The units could fluctuate from being 80-100 Watts low to 80-100 Watts high in a matter or seconds. Polar informed us that the unit is much more accurate when used on the road with the natural vibrations from the road surface being transfered to the chain. While I can't comment specifically on this claim because all our data were collected in the lab, I do have to wonder how accurate the unit would be if it were used over a variety of different road textures or trails.

Another option would be to try one of the many trainers out there with power capabilities. Some can be had for less than $500. And, when you keep your set-up consistent, they can measure power output pretty consistently, though not always accurately.

You might check e-bay for an SRM or powertap. The used ones can sell at a hefty discount. All other issues being equal, I prefer the SRM. It is more durable, can be used with any rear wheel, and will cost you less in the long run than a powertap. BTW, I wouldn't spend the extra money on a professional model as the amateur model does an excellent job of measuring power in most cases.

Another option is to train without a power meter. While they are great training tools, they aren't going to do the work for you. I have had great results from clients who never owned power meters. Perhaps a more important aspect of training is to recognize what it means to really dig deep and give yourself a good butt kickin' on the hard days.

Hope this helps,

Dave Morris
 

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Polar

I know I"ve posted this before but ............I've used the polar power unit on my road bike for 18 months now and I'm totally happy with it. I want to know what my avg power is for specific intervals and rides that I do and it gives me that information at the lowest cost and weight and I'm already using there software for my training calandar.
Is it is accurate as a power tap? Probabley not, but so what. I just want to know if MY power is increasing or decreasing.
 

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Another approach

You can simply use a good trainer (such as the 1UP) and a rear wheel drive speedo that has small (eg .1 or .2 mph / kph increments) and do specific interval workouts at a constant speed, which will mean constant power. Yes, there is a little workout-to-workout variability based on rear tire friction differences, but it well help you get a good, consistent workout over time.

If you read Andy Coggan's material, he preaches training at a specific % of LT (or maximal steady-state) power. Having worked with Dave for years, I believe in the approach that he and Dean Golich have advocated: do the specific workout at the maximum wattage you can sustain and complete the workout. I've used Computrainers for YEARS and love them...just punch in the output in 10 W increments, and CRANK! It is good as you also develop more of a feel for what various power levels feel like. For longer efforts, I have done sustained climbs on the mtb of perhaps 12 min. Those are good because it more closely replicates race conditions. Now, a PowerTap or SRM readout on the mtb would be even better.

Dave is a big SRM fan...and he is Da MAN! BUT, I bought a PowerTap, as I wanted the flexibility of different bikes. I race 700c mtb (29er!) and road, so a sturdy wheel on a 700c rim can be used for both bikes; just purchase another wiring harness. And (although I haven't done it yet) the PT folks tell me that swapping between 130 and 135 axles is a very quick job. My hope is to collect some singlespeed data when my new 29er EBB frame is finished (hopefully in another week or two).

By all means, IF you are comfortable doing intervals on the trainer, check out the various power reading trainers out there...the prices have come down (and are less than the Computrainer, although I doubt as accurate).
 

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I use my trainer in a similar manner as well in the winter. It is great as you don't have to worry about terrain, you can do a constant interval for 20 minutes if you want. All you are interested in is getting faster and more powerful. A trainer can tell you all you need to know, with the exception of the bragging rights I guess.
 

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Here's what I do

upstateSC-rider said:
After reading the Morris and Friel books I'm trying to get everything I'll need to start a more structured training regimen in the Fall/Winter. I'm good to go as far as a HR monitor and a trainer but I'm looking for a way to measure power now. A Power-Tap unit would be my first choice but it's pretty unrealistic for me being that I plan on staying married. ;) I've heard about the Polar S-720/725 with power unit also.
What are some other options to measure power accurately?

Thanks.
Lou.
I'm sure it's not totally accurate, but oh well. I own a 1up trainer, which rules. On their website they have a list of mph = watts. I use a rear wheel computer to keep track of my mph. The list also has data for Kurt Kinetic and Cyclops Fluid 2 trainers. I too would like the nice power meters, but all my $ is in my bikes!!! Check the website- 1upusa.com
 

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Discussion Starter · #9 ·
Dirtdemon said:
I'm sure it's not totally accurate, but oh well. I own a 1up trainer, which rules. On their website they have a list of mph = watts. I use a rear wheel computer to keep track of my mph. The list also has data for Kurt Kinetic and Cyclops Fluid 2 trainers. I too would like the nice power meters, but all my $ is in my bikes!!! Check the website- 1upusa.com
I like that, if it takes X amount of power to turn turn the trainer to Y speed then you just need a little cheat sheet (or graph) at the trainer with you. :)
All hopes of being an elite rider are all but over for me but I'd just like to do a little more consistent work out of my limited training time. And my perceived effort is not very calibrated yet. :D

Thanks for all the help and replies everyone, this is why mtbr is so great.
Lou.
 

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Good point witcomb

witcomb said:
I use my trainer in a similar manner as well in the winter. It is great as you don't have to worry about terrain, you can do a constant interval for 20 minutes if you want. All you are interested in is getting faster and more powerful. A trainer can tell you all you need to know, with the exception of the bragging rights I guess.
I also ride the go nowhere bike in the winter, you really can get longer sustained intervals on the trainer and it is easy to measure progress by mph and your heart rate without having to buy a lot of non-essential bike stuff.
 

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upstateSC-rider said:
After reading the Morris and Friel books I'm trying to get everything I'll need to start a more structured training regimen in the Fall/Winter. I'm good to go as far as a HR monitor and a trainer but I'm looking for a way to measure power now. A Power-Tap unit would be my first choice but it's pretty unrealistic for me being that I plan on staying married. ;) I've heard about the Polar S-720/725 with power unit also.
What are some other options to measure power accurately?

Thanks.
Lou.
Cheapest ergo trainer is the tacx.

Nashbar sells it. use a 20% coupon when available, or scan he returned goods section.

It makes following the Morris style of training a lot easier, or should I say a lot harder because there is no cheating with the power settings. Makes you feel sort of bad because you can't hold a certain power setting that you think you should

I wouldn't call it accurate compared to the higher end computrainer, but I would call it repeatable, with an easy method of putting the bike in and setting the tension on the tire the same, and a calibration method.
 
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