Unexpectedly low "wasted motion"

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BillOsler
Posts: 20
Joined: Mon Apr 04, 2016 10:10 am

Unexpectedly low "wasted motion"

Post by BillOsler » Sat Dec 01, 2018 5:44 pm

On today's ride I did a couple of short hard sprints out of the saddle. I've been trying to improve my sprint technique, learning to tilt the bike left when I push down with the right pedal, ...
Coaches tell me that this technique is definitely faster than having a nice smooth balanced pedal stroke during a sprint ... but it seems to me that it should waste power. Maybe I don't understand what PowerStroke is doing.
At any rate this is a screen shot from the PowerStroke display when I selected one of the sprints from today's workout. The bike was rocking quite a bit from side to side but that's not how I interpret the PowerStroke image
PowerStroke-12-01.png
PowerStroke-12-01.png (284.7 KiB) Viewed 192 times
Is a 15 second sprint too short for PowerStroke to analyze?

Velocomp
Velocomp CEO
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Joined: Fri Jan 11, 2008 9:43 am

Re: Unexpectedly low "wasted motion"

Post by Velocomp » Sat Dec 01, 2018 5:51 pm

If you look at your PowerStroke for the entire ride, you'll find a distinct pattern. Notice that if you select shorter segments, you will find the data more and more spread out.

PowerStroke records 16 times per second, then divides that data into 10 degree segments. What is happening is that, in a 15 second period of time, you have only 24 or so complete turns of the crank...not enough to reliably distribute PowerStroke information into segments.
John Hamann

BillOsler
Posts: 20
Joined: Mon Apr 04, 2016 10:10 am

Re: Unexpectedly low "wasted motion"

Post by BillOsler » Sat Dec 01, 2018 9:08 pm

Thanks. I guess I'll have to figure out other ways to see how much shifting around the bike does when I sprint. I'm still learning technique so right now I'm not generating enough power OR a high enough cadence but i'm told the goal would be closer to 40+ pedal strokes in that 15 second sprint

Velocomp
Velocomp CEO
Posts: 5427
Joined: Fri Jan 11, 2008 9:43 am

Re: Unexpectedly low "wasted motion"

Post by Velocomp » Sun Dec 02, 2018 6:14 am

You'll need several minutes of recording to get useful data. Sprint at a lower level of intensity, so that you can "survive" longer...
John Hamann

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