Frank Krygowski wrote:
On 6/14/2021 11:47 AM, jbeattie wrote:
On Monday, June 14, 2021 at 7:27:35 AM UTC-7, James Carrington wrote:
On Monday, June 14, 2021 at 6:08:25 AM UTC-4, Rolf Mantel wrote:
Am 13.06.2021 um 21:35 schrieb Tom Kunich:

While there are still those who might think it useful I would like to
know why you think it would be useful and what sort of knowledge do
you think that it would impart that you could not detect simply
through your legs without the extra weight of $500 in your wallet?
I'd take a power meter for $100 or so, in the hope that I can see more
easily whether I'm slower than usual

a) due to a bad night's sleep (power low)
b) due to external factors (power normal)

As of today, I can tell easily whether I'm slow due to the wind (speed
difference after the 90 degree bends) but issues like "far too low tire
pressure" and "chain is in desparate need of oil" I only notice
indirectly (Monday after servicing the bike I'm significantly faster
than Friday before servicing the bike).

If the power meter is sufficiently exact, I'd use it to still my
scientific curiosity comparing the wind resistence with various setups
(on the drops vs on the hoods vs recumbent bike, one very full pannier
vs two half-filled panniers etc).

Similary, once in my life I bought a heart rate monitor for cycling
which confirmed that my "feeling good" was a close enough measurement,
and after a few years of bike computers with cadence sensor I'm now
happy with mobile phone GPS without cadence sensor.

Rolf
Power meters are incredibly useful as a metric for fitness and for
targeted training. However, if you aren't a competitive cyclist it
isn't of much more use than any other electronic gizmo. Since I am a
competitive cyclist, I rely on one rather heavily for training. That
said, my use of a power meter is exclusively indoor, since external
variables like weather, terrain, and traffic often conspire to thwart
outdoor efforts. Being in the sport competitively for over 30 years, I
have a reasonably good sense of RPE. Besides that, while racing your
power numbers are largely irrelevant. If you can go with an attack, you
go. Watching a power number is no more than a distraction at that
point. It's not uncommon to see riders both pro and amateur put a piece
of electrical tape over a power display when racing. Sure, you can
analyze the data after and figure out 'gee, no wonder I got dropped',
or 'I really shouldn't have been dropped'. As Rolf points out, the data
can tell you a lot about your level of fitness, either generally or if
you're over-trained. As far as I can tell, there is no one in this
forum (aside from me) who would use a power meter for its designed purpose.

I'm surprised you only use yours for indoor efforts. Even with
weather, terrain, etc., measuring power allows you to maintain
consistent effort, particularly climbing and in headwinds. And can't
pros and amateurs set their screens to not display power? That would
seem like a better option than using electrical tape. Personally, I
just wouldn't look -- but then again, I don't have a power meter.

IME, people purchased power meters for all sorts of reasons -- from just
wanting a gizmo, to serious training to cardiac rehab (or other rehab
like leg imbalance). It's just a measuring device, and one can use
measurements for lots of reasons. I think its a bad value proposition
as a gizmo, but that's just me.

Not surprisingly, I agree. At my age, measuring power would be silly and
depressing. But through most of my cycling life it would have been
redundant. I never had time to "train" in any disciplined way. My
"training" was to ride home from work as fast as possible, at least on
days I caught the first few traffic lights green.

But ISTM one type of racer could make good use of a power meter: A time
trialist. The time trials our club used to put on were on rolling
terrain. I was always concerned about how fast to go out, to make sure I
wouldn't blow up on the final climb. Some trial and error with a power
meter would have been useful for gauging effort.

--

Anecdote: The only time I recall getting a power measurement was when
the university's Exercise Science department offered a bunch of free
testing to faculty members. As a young faculty member, I jumped at the
chance. When I got the printout, it claimed I peaked very close to 2000
Watts.

I was pretty astonished, but didn't know how to interpret that number.
Since then, after learning a lot more about human power, I realized that
had to be metabolic power consumed, not output. I think I need to
multiply by my metabolic efficiency. But if (back in that day) it was
25% or so, it still gives a respectable number.

But then, the older I get, the faster I was.


I’ve temporarily (very temporarily) gone over 746 W on a WattBike that was
set up at the Couer d’Alene Ironman a number of years ago, but my
sustainable power is nowhere near that. A rough “lumber crayon on the back
of an envelope” estimation of peak power in Watts is crank length in mm x
max cadence while standing on the pedals x rider weight in pounds, all
divided by 3370.