« What Is Fatigue? | Main | More on Power Meters »



Feed You can follow this conversation by subscribing to the comment feed for this post.


http://sites.garmin.com/vector/#power is the new Garmin setup. Thinking pretty seriously about buying these.


As a not very good cyclist, I will say this:

1. Learning to use the PM is easy. Run test. Do 20 min intervals @ 90-100 percent FTP. Watch FTP rise. It's that simple. No guesswork-the body responds to stimulus. (Given the limited amount of workout time I have during the winter, I focus on higher intensities than the classic periodization plans.).

2. Learning to interpret the data is a whole 'nother kettle of fish. I've been at it a year, and I now understand how to use it a lot better, and feel like the gains are more consistent. Joe's books combined with the Allen/Coggan book are pretty much all you need. The analysis is a big part of this. If you don't enjoy this part of the tool, the PM is still useful, but it's more fun if you like to use the charts in figuring out strengths, weaknesses, etc. If you do enjoy it, it adds a whole new aspect to the hobby.

3. It is harder to dial in intensities outside than inside. Learning to pace that way in a specific range outside (rather than hammer, pant, recover, hammer) is helpful in learning your limits and pacing, and becoming smoother in delivering power to the pedals.

Could you learn to do this with RPE and HR? More or less, yes-once you dialed in what FTP "felt" like vs what tempo vs VO2, etc., you'd probably find yourself getting it more or less right. But I have no desire to go back.


I noticed that in trainingpeaks. I upload daily including my commutes, though my TSS & IF seem way off (underestimated) but again it is only as accurate as the numbers that I have set for my HR. The thing is for whatever reason (and there maybe many) I get totally different numbers for an indoor threshold test v outdoor test. My FTP is a lot higher outdoor than indoors. Here where the problem is, the numbers that I've set at the moment in trainingpeaks & WKO both watts & hr are based indoors, why because that's where I do all my intervals at the moment & may get out for one or two 4hrs+ group rides at the weekend, because of this my eTSS & IF taken from Edge outdoors are way out. A suggestion maybe to have 'two' sets of ftp & hr values, one for 'outdoor' and one for 'indoor'. When uploading to trainingpeaks have a check mark to indicate if it was an outdoor or indoor ride. Maybe this could be linked into device agent? Just a thought.


So it seems a power meter isn't just a technical training tool but can act almost as a motivational device as well, by knowing your current power level and trying to beat it?

Since a power meter makes tracking progress/improvement easier, it seems it would make training more regimented and productive, since there are specific levels to work against. Definitely a cool product I'll have to check out.


I received my PM, 3 months ago, as a competitive age group roadie, it is the best investment I have made in my training arsenal.
Last week I was doing a crit and could not hold onto the younger more elite riders in the bunch due to some heavy crosswinds. Instead of beating myself up for not being able to hold on, I realsied that my power output was quite high. I continued to focus on pushing my power for the remainder of the 60 min. As a result I improved on my previous CP60. So my session turned into a motivator due to the presence of my PM.

Ted Inoue

Hey Joe,

First - thanks for the years of guidance you've provided. Your scientific approach to training has helped me and teammates reach new fitness levels since the 90's.

Last fall, I rediscovered power meters after a decade hiatus of "just going out and training." As a 47 Y.O. masters racer, I need all the motivation and focus I can get when training - I just wasn't able to go out and suffer like I could in my 20's.

A power meter, combined with the Strava service has taken me back to fitness levels I haven't seen in a long time! I can now compare my own performance and that of others on various training segments so I get to quantitatively evaluate my training in a way just not possible with a HR monitor or timer alone. It's actually making intervals fun again.

So there's the quantitative aspect of power meters that's motivating as well as the social training that is now possible. Combined, I feel like we've entered a new era of training and expect to see a noticeably higher level of competition on the race circuits.

Doug Perry

Garmin's Vector powermeter is scheduled to be available in March, 2012. I believe it will be worth waiting for .... hub based meters, like cycleops, ties you to the wheel. Crank based systems, like SRM, tie you to the bike. With the pedal based Vector, you can switch bikes and wheels ... put on the pedals and your good to go!! It will cost you in between the cost of the hub and crank system ... $1,499.99.

Mikołaj Mucha

Hello Mr. Joe Friel and everyone,

I have a question regarding section "cheating with power". It says that the optimal target power should be determined through training. I have tried to do the research on that, but I'm afraid I don't know how to determine the target power?
Moreover, is it possible to determine a kind of "target heart rate" using HR monitor? I know that hr monitor can be very misleading in the race, but can it be of any help?
So far, I've got to know that one can last up to an hour at the lactate threshold but what about longer events such as 2-3 hours MTB race or a marathon or an ironman?
I understand that there is no easy answer to that, but can You shed some light on that or suggest some reading?

Last but not least, because it's my first time writting here, I would like to thank Joe Friel for all of His work, especially for coming to Poland, I hope You liked the sightseeing and the museum :)


joe, thanks for the insightful article! i used to have a quarq but didn't know how to use it well, so i've sold it.

now, you blew me away with the Avg Normalized Power / Avg HR so much that i'm back in the market for another quarq!

this ratio is what i've been sorely missing my first time around with a PM! what is this metric called?


"Now I can precisely compare output with input by dividing the average (or, preferably, “normalized”) power for a workout by the average heart rate. An increasing value for similar workouts tells me fitness is improving."

What's this metric called ?


great article, joe!

"Now I can precisely compare output with input by dividing the average (or, preferably, “normalized”) power for a workout by the average heart rate. An increasing value for similar workouts tells me fitness is improving."

that's what i've been looking for! does this articular metric have a name?


Power meters definitely give athletes an edge over their competition and are great tools for training. However, the issue that I've always had is the perception that power meters are going to magically make "athletes" faster. To often times I've seen amateur athletes spend hundreds of dollars on a power meter when what they really need to do is just spend more time riding and not worrying about how many watts they're pushing. For instance, I know many amateurs that are pushing between 100 and 130 watts (maybe around 15mph or so). For the first month or so, they spend all of their energy concentrating on power (instead of just riding) and then get discouraged, because they aren't getting any faster. What I would like to know is if you have any suggestions on who should purchase a power meter? Is there a certain athlete threshold? Some type of a rule of thumb? Some type of a test that can be used to determine if somebody is ready for a power meter?

I appreciate any feedback. Thanks.

Joe Friel

Yobikwhatus - I'd suggest that any rider who is performance-oriented can benefit from using a power meter once they know how to use the meter and analyze the data. I have a book coming out in late summer that explains all of this.


Thanks Joe. I'm looking forward to the book.


I am about to try the new iBike Newton+. I believe, compared to SRM it is only about 5% off. It is MUCH cheaper than any other PM around and no need to change hubs or wheels. Is 5% off ok?

Joe Friel

Lauren, That's a great way to get started with power. Your bathroom scales may be a off a bit also. But the most important thing here is to know that your body weight changed by x--not that the scales changed by x.


I am a 65 year old fitness rider doing a 20 to 40km balls-to-the-wall ride five days a week and a 100 to 150km ride on the weekend. I am highly competitive, against myself (my last ride). In the winter i ride a trainer with a "sort-of" power meter. I frequently found that the wattage output on the power meter was reminding me that i was slacking and that i was responding to that by pushing harder. Very motivating. Got a power meter. What a difference. Not only do i have the motivation, but i have also figured out how to do those 100 to 150km rides and finish strong by pacing myself as opposed to blowing it all halfway because i was feeling energetic at the moment. My times are also wayyyyy down. It has also helped me to identify what kind of rides i am best suited to and how to select and train for different kinds of rides. Will be entering my first race this summer, just to see how i stack up against others of my age group.Serious money but well worth it IMHO

George Fair

Using a quarg today outside for the first time, It's very overwhelming with all of the data. I am hoping that the 7 mo. I have until Lake Placid will pay dividends on the course.


I just wanted to comment that it is possible to "get in the game" of power without breaking the bank. The sacrifice that I made was to buy a used, wired (not wireless), power meter. I got a used Cycleops SL Wired power meter hub and Mavic Open Road Pro wheel for $350. It includes the Cervo computer and cadence sensor as well. So far, so good. One side note is that I did have to buy the usb download kit ($50) in order to load my workouts into the Cycleops software onto my PC (free). The software gives you the ability to upload the workouts to all of the big websites used for fitness tracking and analysis.

One neat thing that I noticed is that since it is an older head unit, it does not have to pair with a heart rate monitor strap. Most modern devices must pair with the heart rate monitor strap (coded straps). This is so that you don't pick up the signal from other heart rate monitors nearby. So, I'm able to use the heart rate monitor strap that I have for my Garmin Forerunner watch. Both the watch and the Cervo will pick up the HR. Since the Cervo is not a GPS computer, I still use my Garmin watch to get my route data. I use the Cervo to gather HR, power, cadence, etc.

I think that you could get a wireless Cycleops power meter and wheel for around $700. Or you could buy a Cycleops wireless hub, and get your bike shop to lace it into a wheel that you already own. You can pick up the hubs for a reasonable price on e bay.

One last thing...I really like to do some of my spring interval workouts on the bike trainer indoors because I can really dial into my power training zones. The trainer always seems more difficult to me, but I know I'm training in the right zone and getting the benefits that I'm looking for.

Carl Carl

Any thoughts on simply using the PM indoors on a Wahoo trainer to track your progress (combined with HR data). That's my current plan, but I've not purchased the trainer yet. My thoughts are the indoor trainer would provide for consitent repeated (identical) workouts for comparison to guage progress. The PM on the indoor trainer should allow the rider to specifically increase output power by a set amount during a ride for a Conconi test to determine heart rate at Lactic threshold, as described in "Traning, Lactate, Pulse Rate" by Peter Janssen

Joe Friel

Carl--You certainly can do any riding or testing indoors. Some people thrive on it. Others hate it. So up to you.

Verify your Comment

Previewing your Comment

This is only a preview. Your comment has not yet been posted.

Your comment could not be posted. Error type:
Your comment has been saved. Comments are moderated and will not appear until approved by the author. Post another comment

The letters and numbers you entered did not match the image. Please try again.

As a final step before posting your comment, enter the letters and numbers you see in the image below. This prevents automated programs from posting comments.

Having trouble reading this image? View an alternate.


Post a comment

Comments are moderated, and will not appear until the author has approved them.

Your Information

(Name is required. Email address will not be displayed with the comment.)

Joe Friel's Sponsors

Blue Competition Cycles
"Specialized Bikes is my newest sponsor. I’ve been impressed with their bikes for a long time so I tried one. Had to have it. What a great ride!"

D2 Shoes
"I’ve been using custom-made D2 Shoes for years. Currently on my fourth pair. And, yes, they have midsole cleats as described in my blog."

ADS Sports Eyewear \
"ADS Sports Eyewear makes all of my glasses for casualwear, reading, cycling, golf and more. Hundreds of models from all the major manufacturers."


Subscribe via Email

Enter your email address:

Delivered by FeedBurner