Home General Training Discussions

Are all watts created equal?

I have noticed something that I'm hoping some of the smarter folks can shed some light on and provide some tips & insights....  Might be normal but just curious....

So I've noticed I can hit the same watts on a hill vs. a flat but those same watts on the hill feel like Z5 but the flat will feel like Z2/Z3.   Is this normal?  Is it mental?  (I am not good on hills)  My body - variation of fast vs. slow twitch muscle fibers?  Strength (or lackof) in the muscles primarly used in climbing vs. flats? I would think 150 watts would feel the same no matter what.. but I could be wrong....

Comments

  • Most people can produce a few more watts on a hill than they can on the flat as the hill sort of creates watts for you (or you stop and fall over) vs a flat where "it's all you" in terms of power. As far as hills being harder, my first question would be---what is your cadence when climbing vs on the flats? It maybe a matter of being in your cadence comfort zone on flats vs mashing the pedals on the hills with a lower cadence. There is some variation in position when people are climbing vs on the flats and that may account for it, but there is also a mental game of putting up 85% of your watts and only going 6 mph--it can make it feel harder than it really is.

    Those are my thoughts on it, but I'm sure one of our WSM medical people will have a more scientific take to answer some of your questions.
  • They're not created equally. For example, averaging the same watts in 95 degree heat takes a much larger toll on your body than if it were 65 degrees.

    That stated, I think watts going uphill or into the wind are pretty much the same as riding in the flats or into calm winds. Assuming consistent temperature and how you're feeling physically i.e.. the same ride. Going uphill can put you in a slightly different position so maybe it feels different.
  • I had the exact same thought as Keith - what is your cadence on hills vs flats?

    I've certainly found that if I'm cruising along on a flat, producing X Watts and Y cadence (Rich's vernacular has been seeping into my brain!), and then I hit a hill - my power may show the same value of watts, but my cadence drops. If I re-gear to get my cadence back to Y, I find that the power actually shoots up past the original value of X! I haven't completely figured it out, but my thinking so far is that there is a rounding/estimation error due to sampling rate - ie, the powermeter samples torque at regular intervals, and if I'm mashing, then relatively speaking, there is a larger divergence between various samples than if I am spinning at a more 'normal' cadence, where power output is more even and measured throughout the pedal cycle.

    If you have WKO or GoldenCheetah - take a look at the PF/PV graph. There are 4 quadrants - top left is low speed high power (ie, mashing), top right is high speed high power (probably more seen with sprinting), bottom left is low power low speed (bonking!), bottom right is high speed low power (spinning easily). During your next ride, take an interval during a flat, and take an interval during a hill as you normally do. Then take another interval where you are mashing up hill, and then another interval where you are spinning up hill with a higher-than-normal-for-you cadence up a hill. By looking at the various plots for those intervals on that graph (and comparing the RPE), you can determine what kind of rider you are - and whether you are perhaps mashing just a tad going up hills and finding the limits of the fast twitch muscle fibers in your leg muscles.

    (that last bit is my own SWAG based on my own personal observations of my own riding)

  • I think Keith kind of hit it. But are we talking about TT or road bike? Maybe you are just not comfortable climbing on a TT bike if that is the choice.
  • Keith is spot on. 180 watts at 85 rpm has a very different amount of muscle activation than 180 watts at 65 rpm, and feels harder. (BTW, so does 180 watts at 125 rpm, but for different reasons).

    In addition, trainer companies have spent a lot of time trying to get the flywheel weight perfected to create a 'road-like' feel. I believe that the heavier the flywheel, the more like going uphill, as the wheel needs to be reaccelerated more at the top of the pedal stroke, which feels like more work. Whereas, the lighter the wheel, the more like the flat, where the application of power is over a slightly shorter burst to keep the wheel accelerated, which feels like slightly less work.

    I also think that this is why I have a much harder time keeping the watts up at target pace during a sprint/Oly race, even when I've demonstrated the ability to do it in training (I have virtually no flat ground around me, so don't often get to practice)
  • I think everyone hit it, but I would just say that watts are the product of torque (pushing force on the pedal) and cadence (spinning the pedal). Climbing is generally more torque with less cadence to deliver 150 watts. Flats are less torque and more cadence to deliver the "same" 150 watts. Depending on your pedaling style, "spinner" versus "masher", you will find one more preferable than the other
Sign In or Register to comment.