TESTING POWER VS NORMALIZED

jettshawn

Iam getting ready to do my test this coming week and i was looking at what the coaches say to do and i might have been doing it wrong. i have been going off of the averdge power for my last 42 minute test. Am i supposed to go off of normalized power. If so what is the diffrence. It looks like my averdge power and normalized are about 10 watts diffrent. Please help

zildgen

Shawn I'm new to power and have only done 2 tests so other will have more input I'm sure but for the 42 min test we should use NP. NP is an estimate of the power that you could have maintained for the same physiological "cost" if your power output had been perfectly constant and gives a better measure of the true physiological demands of a given training session. Not sure I have a good enough handle on the concepts to give more than the definitions. I look forward to hearing others responses.

Al Truscott

The Normalized Power for the full 42 minutes of the test becomes your F(unctional) T(hreshold) P(ower), to be used during subsequent training sessions.

For the 20 minutes x 2 when you were "on", your avg power and NP were probably closer to each other. It's the two minute recovery period in the middle which might throw things off a bit, I suppose due to the magic formula which calculates NP.

jettshawn

Thanks guys, I still don't understand NP, can anyone give me a dumbed down definition

Daniela

Somewhat related, but also somewhat off-topic....

The first post mentions having a difference of 10 watts between Power and NP. My tests have only been 1 watt different between P and NP. I do use the NP wattage as I've read to do so in the wiki. My FTP is around 200, with my 2' RI being around 65-75% of the final NP. Is a 10 watt difference normal?

Matt Samojeden

Average power is the work you did that will get you around a course in a overall time. The higher the average power the faster you will get around the course.

Normalized power is a construct that attempts to tell the physical impact of the average watts you produced. How tired did I get from the average watts I produced. Riding at a steady easier than riding with high variability in your power levels.

For riding with power see in our Wiki http://endurancenation.us.dnnmax.com/Resources/Wiki/tabid/108/Default.aspx?topic=Racing+with+Power+Kit


On NP Also see http://home.trainingpeaks.com/articles/cycling/normalized-power,-intensity-factor,-training-stress-score.aspx

We have an NP calculator if you want to do some what if interval calculations, see racing calculators on http://endurancenation.us.dnnmax.com/Resources/Wiki/tabid/108/topic/Calculators/Default.aspx


Example FTP test watts 100% for the 2X 20 and 70% for the 2 min.
So 200 W for 20’ 140 W for 2’ and 200 w for 20’. This test givea an NP of 198.2 W and an Avg W of 197.0 W.
A ten watt difference in NP vs AVG w implies a lot of variability in the power level rode during the test. Smoother is better.

tuckerm

Matt is correct, as usual. I remember Coggan stating in the Wattage forum once that basically you could average just the 2 20' intervals as the difference is not that great as Matt has shown. He did write the book.....

Tom Glynn

Not all bike computers will display normalized power (NP), so my thoughts would be, if your device displays NP, then use that number to do all your intervals at. If it doesn't then use average power (AP), preferably excluding zeroes, as it will be closer to NP to guide you through your intervals.

If you ride consistently when doing intervals then AP and NP should be pretty close.

I think it's better to see your goal on the handle bars than trying to estimate a number that requires a download into WKO after the ride to figure out.

@Shawn, a really dumbed down explanation for NP. If you ride for one hour holding exactly 150 watts, then your average watts are 150. If you ride for 30 minutes at 100 watts and 30 minutes at 200 watts your average power is still 150 for the hour, but they are completely different rides. NP is a complicated math formula that gives more weight to hard work and less to easier stuff, so in my example the ride for one hour @ 150 watts the AP and NP would both be 150 but in the second example, the AP would still be 150, but the NP would be s slightly higher number, say 160.

Coach Rich

This is how I see Pnorm vs Pavg and other related topics:

• Pavg is the physics of you moving your bike down the road. That is, two riders, equal bikes, weight, aero-ness, everything riding averaging 150w = same bike split
• Pnorm is how tired you made yourself producing the physics of 150w.
• As Ironman athletes, we want to produce the right average watts, given our fitness, in a manner that leaves as little tired as possible. IOW, Pnorm very close to Pavg.
• This is Variability Index (VI) = Pnorm / Pavg. We want this very low, ie, a very steady, nearly contant power ride...or at least not tossing out big watts on hills or loonnggg coasting sections = higher Pnorm = we made ourselves comparatively more tired while producing the same Pavg = the same bike split.
• You always want the number on the dial to be the number you're supposed to push in real time:
• If you have a PM that displays Pnorm, IF, etc, you want to look at current watts -- the watts/physics you are doing right now.

Paying attention to Pnorm and other metrics is largely a matter for post ride stuff, but if you have Joule or other WKO+ capable (?) monitor:

• Mine displays current watts, Pnorm, and IF on the home screen.
• I ride so that currents > Prorm = pushes IF up = pushes Pnorm up = pushes current watts up...next thing I know I'm pretty much TT'ing everywhere I go. Very evil way to train for informal, go that way as fast as I can sorta rides
• For formal intervals rides, just look at current watts and don't worry so much about Pnorm...unless your route is rolling, has you coming off the gas, etc = instances that will take a bite out of your Pnorm and, if you're watching current watts at the same time, will drive you to work hard to push Pnorm back up.