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Power Numbers

new2703new2703
in General Training Discussions

So last night I was doing an FTP work out on the bike 3x10 minutes on stationary trainer.  Noticed something interesting:  

First 10 min.  Avg Power 272 avg speed 22.0mph

second 10 min:  Avg Power 266.  Avg Speed 22.5

Third:  Avg Power 271, Avg Speed 22.2

Shouldn't speed decrease as power decreases?.  Not sure how with less power was able to generate more speed on a stationary trainer

 

Comments

  • Satish PunnaSatish Punna
    could be a function of your trainer/tire warming up.  Was your heart rate and rpe relaticely consrant?
  • new2703new2703
    Warmed up for about 15 minutes prior. Didn't wear a HR monitor this time but RPE was relatively constant
  • zwubazwuba

    To me that just means that the resistance had increased ... if you're riding on a trainer it may be an effect of the increased rolling resistance caused by temperature increase on the tire vs roll.

  • Satish PunnaSatish Punna

    Posted By Satish Punna on 22 Feb 2013 01:20 PM


    could be a function of your trainer/tire warming up.  Was your heart rate and rpe relaticely consrant?
    pardon my spelling I'm a terrible typist.


  • John WithrowJohn Withrow
    Agreed with the above. If you're using a Powermeter (and not "virtual power") then speed is irrelevant on a trainer. I would assume that as the fluid warms up, the resistance curve will change slightly due to the lower viscosity of the warmer fluid. Also, as your tire warms up, your tire pressure might go up by a tiny bit which would be similar to tightening your wheel to the drum of the trainer by just a little bit.

    BUT again, it doesn't matter one bit. The Power you put out is what matters. RPE and HR are also important to observe at these power levels, but they are a distant second order to Power. And something like speed would be more like the tenth order. So my advice is to remove speed from your computer readout and just look at power and cadence instead, especially when indoors on a trainer.
  • new2703new2703
    Don't really focus on speed. It was really just an observation but also made me wonder if something was up with Pwer tap
  • cgres123cgres123
    something else to take in consideration would be to cadence you're doing your sets at.
  • new2703new2703
    @ Dave. First two sets gearing and cadence was the same, 85. The third cadence was increased to 90.
  • cgres123cgres123
    was the gearing all the same too.
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