Comments on: Average vs Normalized Power

By: Seb

Seb — Sun, 25 Oct 2009 04:10:07 +0000

Great post on NP!

By: Melbourne to Ballarat - Crosswinds and Number Crunching

Melbourne to Ballarat - Crosswinds and Number Crunching — Wed, 19 Aug 2009 23:21:08 +0000

[...] climb to Pentland hills and continued for the next 40 or so kilometres, I put out 341 watts with a normalized power of 357 (5.3 w/kg). This is indicative of a couple of things; the wind was strong and the pace was [...]

By: Tom

Tom — Wed, 19 Aug 2009 02:05:54 +0000

This is not a good example; If you take a close look at these rides you will see the the first is 58.62km and the second is 49.34km! Honestly at this low wattage and looking at the data I think you will find that the NP is VERY similar. Also, RPE is only useful if one shows the training diary. What was the load 5 days prior to the 05/22/09? What was the load 5 days before the 05/29/09?

By: Mr W

Mr W — Wed, 08 Jul 2009 22:29:22 +0000

I can’t believe anyone would look to averages as a useful summary statistic, I say this of course after having 10 yrs of post graduate training in statistics :-)

I think Normalized power is a great start although I am still skeptical, as I would have to read the book to see how “physiological cost” is calculated. Just like max HR (in my thirties and I still have a “freakishly” high 210 max) my guess is the energetic costs per power zone vary greatly from person to person and will be very hard to predict (just as max HR is quite hard to predict accurately). For example, I am willing to bet your muscle fiber composition alone (not even touching to differences in metabolism – e.g. catabolism and anabolism) would create very different cost profiles, thereby negating to some degree the concept of normalized power. That said, it would be worlds better than a simple average of the raw readings.

Speaking of analyzing workout data, I am terribly disappointed that none of the programs I have played with to date (e.g. Garmin and trainingpeaks online) have let me download the data as a .csv (or equivalent) so I can start doing my own analyses! Does anyone have a different experience?

And as a side note, I found a statistical error in the iBike software a while back, when I contacted the makers they basically told me I had no idea what I was talking about and basically got no where with them. I was a bit annoyed with the experience as I was giving them free consulting, something I usually charge $200/hr for and I had even went so far as to confirmed the error with 2 people (both with PhD’s in statistics) prior to contacting the maker.

So you may not be surprised that I am a tad skeptical with what any of these programs are even doing with our numbers!!!

By: Gene Nacey

Gene Nacey — Sat, 04 Jul 2009 12:59:26 +0000

Your reference to HR monitoring is quite valid, only instead of the concept of “average” vs “normalized”, the common approach is to use “time in zones”. In the world of HR training, Sally Edwards’ Heart Zones emphasize the different benefits of training in each zone, and thus any good HR monitor will give you “time in zone”. Just getting into Power Meters myself, I’m not sure if the software out there for tracking power will also give you “Time in POWER zones” – is this something people look at?

By: Chris N

Chris N — Fri, 03 Jul 2009 22:44:04 +0000

Hi Buttsy, I am at the Freedom Machine in Prahran Melbourne, and am one of those “Boys with all the toys” kinda guys. I was the same, had tried a few wattage units without any satisfaction. I did get a Powertap in December and found it to be the most useful tool I own. It is amazing how it changes your training mind. You start doing intervals properly, Seatet Hill climbs etc, and you can quantify your improvement so accurately. I even can quantify the power I can gain or lose depending on my set up (on the Drops/on the Hoods/shorter stem/longer stem etc)! The Powertap does come with a computer head and a fantastic download program, so you dont need a Garmin. But of course I have one! I have used Garmin now for a couple of years and found the User friendly nature of it such a pleasure to use. The only downfall with this combination is Garmin have not quite worked out a great program including wattage, however the best combination I have found is Sportstrack if you own a Garmin and Powertap. Sure this total package is not cheap, however I can definitely suggest that it is better spending a few Grand on this combo, than race wheels. I have tried Polar (terrible), IBike (great if you are a triathlete (not suitable for a roadie) and the only unit I suggest that is probably an improvement is SRM, however your bike will need to be mortgaged!

By: Buttsy

Buttsy — Fri, 03 Jul 2009 12:15:55 +0000

I looked at a Garmin 705 this week and I want one although then you have to buy a wheel to use with it…….what is a good Power Meter to use????? The Garmin looks great to race yourself and map your rides…..

Power training is something I have never done. I own a Polar 725 with Power (bought it overseas and cheap) I had it on my road bike for a while but never really used it….What is a good Power Meter?

By: Groover

Groover — Fri, 03 Jul 2009 05:58:42 +0000

Thanks for explaining normalised power vs average power. It makes perfectly sense. I will definitely read Allen and Coggan’s book now, too.