First ride with a Power Meter wheel
 

Today we had a testing session with a few guys from the club. A couple of the team own Power Tap wheels, so the plan was to have everyone cover a time trial with a wheel installed and then look at the pretty graphs.

Course: 16km (8 out, 8 back) of moderately undulating road, slight cross/headwind (easy in parts, noticeably tough in others).

Set up: ride solo, PowerOps head unit in jersey pocket (ie riding 'blind')

Results: Not as good as a couple of the riders I think I could keep up with, but lots learned.

Ave power 205 watts. Ave speed 30.5km/h. Max power 545watts. Max speed 40km/h. Power to weight...not great as I'm 94kg (207lb)!

Lessons?
- Coasting/backing off power downhill is easy to do, even while picking up pace - but the reduced power output hurts your average!

- Riding 'blind' (ie with no computer) really makes a difference. My Garmin 305 just died, so I had no speed, cadence or HR to monitor. I'm sure that with that I would go faster/harder/more consistent - but if I had the PowerOps unit it would probably be even easier.

- New toys (even if borrowed) are fun!

Was it Glorious?

Yes it was - I even have the sunburn marks to prove it...

The better power number for a longer effort is Normalized Power to reduce the impact of coasting - http://home.trainingpeaks.com/articl...ess-score.aspx

Do you have Cycling Peaks software? This is a must as far as I am concerned.

Do you have the Coggan book? This also is a must. http://www.amazon.com/Training-Racin.../dp/1931382794

Yes, they are fun, and can be very help if you are working to become a stronger rider. I've been riding less than a year and don't race, but feel that my PT wheel was money well spent. Great motivation, particularly on solo rides. Also great when you want to do more structured/measured training. The thing does not lie (good and bad sometimes).

Got the book, but I'm having trouble getting through it....Too busy riding :)
I have some vacation coming up so I hope to tackle it then...

I too just took my first ride with a PT wheel, a quick 9mi after work loop to make sure thing are running right before longer ride this weekend. I have confirmed that I am out of shape (unless round is a shape...or pear, is pear a shape?)

Total dist: 9.32mi
Total time: 00:33:33
Avg speed: 17.2mph
Avg watts: 172 (stop laughing)
Max watts: a 5sec spike up to 629 as I climbed a 9% grade to get out of my subdivision (seated if that makes a diff)
Avg watts/kg: 2.05 (max 7.5)

now I have to do all the baseline tests and such and come up with a reasonable training regimn for someone who doesn't plan on racing but still wants to get the most out of what little ride time I get....while still training for distance so I can do the Pan Mass Challenge this August (163mi over two days).

new toys are fun ;)

You have just discovered one of the major benefits of doing TTs with a PM. It reminds you to keep the watts cranked on downgrades. As you noticed, they watts naturally drop off quite a bit unless you focus on sustaining them, and this can cost you quite a bit of speed in a TT.

+1 Once you get your FTP you may take it down a notch on the climbs to keep from exceeding FTP for too long and crank it on the descents, when everyone else is letting up. GL

This was actually easier to see looking at the data file in excel - for some reason running your eye along the rows made it easier to see than in the clever graphs in the PowerAgent software.

Next time I'll tape the display to the handlebars so that I can see it. Might be good to work out which guys did the test with the unit in view (I think that only two guys had the mount on their bars).

So why did you want a PM even if you don't race? Just for motivation? Have you tried racing before? Just curious.

Power Meters are for pedestrians. Real cyclists like myself use dynamometers. We obviously can't bring them with us, but it's the price we pay for having a couple hundred horsepower in our legs.

I recall phrases around this sub-forum along the lines of "dailing it up to 400" to drop someone etc. Never really could put that into context until now.

One of the top end riders here said he'd look at my data and make some comments about it and offer some suggestions. This has been really valuable - I owe him!

He also sent me a picture of one of his rides - a ITT up a hill that we regularly ride here. I can tell the main landmarks from the shape of the various lines of the graph etc, so I have a good picture of what is going on.

The HR climbed nicely from 140-180 in a nice smooth curve. Cadence sat between 80-90. Speed sits between 22-24km/h early, changing to 15-20 later in the steeper parts. I go up this hill between 12-15 on a normal ride, might keep it over 15 on a TT (ie race pressure, going to destruction).

But what is freaky (to me anyway) is the power. His average power is (just an estimate from looking along the graph at his very constant power line) is about 420-440watts. The fluctuations every now and then have a range of 380-500. Peak in a couple of spots is 640+.

That just seems scary. He is training to represent his home country at the Commonwealth Games (trying for selection), so I'm guessing he's pretty damn good!



PS - and I did just look up the price on a PowerTap hub...not going to happen soon, but if any of the guys in my town want to upgrade to a new one and sell the old one, I'm waiting.

Stating the obvious here, but it's been very helpful for my training as a poor man's PowerMeter / Computrainer:

Cycle Ops 2 Fluid Trainer + Bike Computer with speed (+HR) sensor. Obviously not translatable directly to road use, but you can get a proportional estimation of power by using the wheel speed. The first few times I did this for 60-90 minutes, I was surprised at how badly my speed/power was dropping off at the end of the ride - with no coasting or stopping on the trainer, you really get a more honest workout. For me to hold a steady speed/power on the trainer, the first 15 minutes tends to feel surprisingly easy and doable, where as minutes 75-90 have me working pretty hard.

This setup is also great for interval work, to make sure you're being steady on the intervals. Costs a lot less than a PM or computrainer as well!

agree. the brain instinctively tries to maintain constant speed, not constant watts. depending on the wind or grade the brain will be pushing your legs less or more.

i wish i had a power meter.

I get that and the pont in the post above.

I do ease off on the downhill but I see this as recovery during the TT. I ride off my HR only (not speed or power). I don't / can't maintain high HR throughout the ride so I consider slight downhills as respite.

Is the most efficient approach to keep power constant?

In the meantime (ie before I go all fred and buy some schwag in the form of a powertap)...

I'll just do some workouts on the bike in the gym and watch the watts more closely than any other variable.

Good question. I think the truth lies somewhere in between. In 20-40 minute TTs I sustain an average HR of over 170 (175 or so), which is very high relative to my max of about 185 (that's about 95% of max HR). So you probably can sustain a higher HR than you think you can. There are some longer downhill stretches in some of these TTs, and you do need to keep the hammer down.