PowerCranks Study

This from Frank Day's recent Newsletter...

[The first criticisms I heard about the PC's came from those who said
"well, if they are so good, why aren't the top cyclists using them?"
Well, that argument became easy to rebut in the last year or so. But,
the other criticism has been that "there has been no study proving the
worth of the cranks and substantiating the claims." Well, I am glad to
report that drought is about to end. I have been informed (and have seen
the galleys) that the first study of training effectiveness in trained
cyclists is to be published in November. I must say, based upon the
study design, I would not have predicted the magnitude of the benefits
they found. But, I shouldn't say more until it is published. I will, of
course, put a link to the study once it is available.]

I'll look forward to reading the publishing and debating this a little
more.

Phil Holman

Phil Holman writes:

This from Frank Day's recent Newsletter...

# The first criticisms I heard about the PC's came from those who said
# "well, if they are so good, why aren't the top cyclists using them?"
# Well, that argument became easy to rebut in the last year or so.
# But, the other criticism has been that "there has been no study
# proving the worth of the cranks and substantiating the claims."
# Well, I am glad to report that drought is about to end. I have been
# informed (and have seen the galleys) that the first study of
# training effectiveness in trained cyclists is to be published in
# November. I must say, based upon the study design, I would not have
# predicted the magnitude of the benefits they found. But, I
# shouldn't say more until it is published. I will, of course, put a
# link to the study once it is available.

I'll look forward to reading the publishing and debating this a
little more.

This sounds more like a book promotion than a report on the cranks.
Barkers at circus sideshows show more than this lead-on. How can you
repeat such jive? By the way, remind me of the principal behind PC's.
Are these the cranks that do not come around by themselves and require
pulling up to make them remain synchronous (180 degrees apart)?

Jobst Brandt

wrote in message
...
Phil Holman writes:

This from Frank Day's recent Newsletter...

# The first criticisms I heard about the PC's came from those who said
# "well, if they are so good, why aren't the top cyclists using them?"
# Well, that argument became easy to rebut in the last year or so.
# But, the other criticism has been that "there has been no study
# proving the worth of the cranks and substantiating the claims."
# Well, I am glad to report that drought is about to end. I have been
# informed (and have seen the galleys) that the first study of
# training effectiveness in trained cyclists is to be published in
# November. I must say, based upon the study design, I would not have
# predicted the magnitude of the benefits they found. But, I
# shouldn't say more until it is published. I will, of course, put a
# link to the study once it is available.

I'll look forward to reading the publishing and debating this a
little more.

This sounds more like a book promotion than a report on the cranks.
Barkers at circus sideshows show more than this lead-on. How can you
repeat such jive? By the way, remind me of the principal behind PC's.
Are these the cranks that do not come around by themselves and require
pulling up to make them remain synchronous (180 degrees apart)?

Yes, that's correct Jobst. Reading between the lines of the newsletter,
it looks like the study will reveal that training with the cranks will
increase power output by 'x' amount. This might be a little more
newsworthy than the umpteenth thread on shimmy but that's just my
opinion. We'll just have to wait and see.

Phil Holman

Phil Holman writes:

This sounds more like a book promotion than a report on the cranks.
Barkers at circus sideshows show more than this lead-on. How can
you repeat such jive? By the way, remind me of the principal
behind PC's. Are these the cranks that do not come around by
themselves and require pulling up to make them remain synchronous
(180 degrees apart)?

Yes, that's correct Jobst. Reading between the lines of the
newsletter, it looks like the study will reveal that training with
the cranks will increase power output by 'x' amount. This might be a
little more newsworthy than the umpteenth thread on shimmy but
that's just my opinion. We'll just have to wait and see.

There is no doubt that adding the effect of lifting (actually pulling
back, lifting and pushing forward over the top will impart more power
to cranks, however, it will not produce more power from the rider for
a given aerobic level. Quite to the contrary. Engaging more muscles
in propelling the bicycle burdens the heart and lungs with the
overhead of more muscles rather than using the principal ones that are
naturally used. If this were not so, foot plus hand cranks would
produce a greater speed in TT's, flat and hill climbs, but they don't.

Anyone who has not trained with these cranks cannot ride with them,
the requirement to keep positive forward torque on both cranks
throughout rotation is difficult to accomplish. I'm sure that Lance
Armstrong could not ride rollers with these at the bicycle show,
something no bicycle racer I saw at InterBike 2002 do. If these
cranks did what they claim to do, we wouldn't see riders dominate
in races against PowerCrank devotees.

Let's not overlook that with conventional cranks, the feet an legs are
balanced and that it take no effort to rotate the cranks forward,
clipped in and with non chain. With Power Cranks, this takes
considerable effort, the feet not balancing each other.

The limit of climbing hills or flat TT depends on aerobic capacity.
That is what good bicycle racers have that others don't.

Jobst Brandt

wrote in message


There is no doubt that adding the effect of lifting (actually pulling
back, lifting and pushing forward over the top will impart more power
to cranks, however, it will not produce more power from the rider for
a given aerobic level. Quite to the contrary. Engaging more muscles
in propelling the bicycle burdens the heart and lungs with the
overhead of more muscles rather than using the principal ones that are
naturally used. If this were not so, foot plus hand cranks would
produce a greater speed in TT's, flat and hill climbs, but they don't.




Rowers combine arm and leg power to improve performance and it does not
burden their heart and lungs. If cyclists had the correct linear pedaling
technique, they too could combine the pushing and pulling on fixed normal
bars for additional pedal power without overloading their heart and lungs.
The most efficient pedaling is the technique that enables you to apply
very effective power to the pedal from 11 to 5 'clock regardless of what
your cadence is because this enables you to use a higher gear for the same
effort of a rider who does not have this technique. The pulling up is done
by the arm not the leg.
The explanation for the ineffectiveness of Powercranks is that the pulling
power of the leg is only effecive at a low cadence or when out of the saddle
and even then can only be used for short periods.






Let's not overlook that with conventional cranks, the feet an legs are
balanced and that it take no effort to rotate the cranks forward,
clipped in and with non chain. With Power Cranks, this takes
considerable effort, the feet not balancing each other.



If you were pedaling for most benefit, the feet would not be balanced as
you should be unweighting the idling pedal as soon as you stop applying
the power, making the most out of the assistance of gravity. In that one
instance Powercranks could prove to you the error of your ways.



The limit of climbing hills or flat TT depends on aerobic capacity.
That is what good bicycle racers have that others don't.




True but knowing how to get the most out of your pedals and cranks can
help you to make the most of your aerobic capacity.

RE/
Rowers combine arm and leg power to improve performance and it does not
burden their heart and lungs.

I'm not much of a rower - but I did belong to one of the local barge clubs for a
couple years and have *lots* of hours on a Concept II rowing ergometer.

I would disagree with the idea that rowing uses the arms for anything but
connectors. For me, at least, rowing is a series of dead lifts. Virtually no
arm effort is involved besides hanging on to the oars hard enough to transfer
power.
--
PeteCresswell

In article ,
(n crowley) wrote:

Rowers combine arm and leg power to improve performance and it
does not burden their heart and lungs.

Yes it does. Rowers are far less efficient aerobically than cyclists,
and cannot keep up competitive efforts for an hour or more at a time,
as can cyclists. It's very simple: more muscles in use increases the
burden on the cardiovascular system.

If cyclists had the correct linear pedaling technique, they too
could combine the pushing and pulling on fixed normal bars for
additional pedal power without overloading their heart and lungs.
The most efficient pedaling is the technique that enables you to
apply very effective power to the pedal from 11 to 5 'clock
regardless of what your cadence is because this enables you to
use a higher gear for the same effort of a rider who does not
have this technique. The pulling up is done by the arm not the
leg.

You must have an interesting position on the bike, since you seem to
be pedaling with your hands on your ankles so that you can pull your
feet up.

N? Crowley writes:

There is no doubt that adding the effect of lifting (actually
pulling back, lifting and pushing forward over the top will impart
more power to cranks, however, it will not produce more power from
the rider for a given aerobic level. Quite to the contrary.
Engaging more muscles in propelling the bicycle burdens the heart
and lungs with the overhead of more muscles rather than using the
principal ones that are naturally used. If this were not so, foot
plus hand cranks would produce a greater speed in TT's, flat and
hill climbs, but they don't.

Rowers combine arm and leg power to improve performance and it does
not burden their heart and lungs.

I think you'll find that rowers row with their legs, their hands and
arms functioning much like the foot and ankle of the bicyclist at the
ends of a pedal strokes where inconsequential power is transmitted.

If cyclists had the correct linear pedaling technique, they too
could combine the pushing and pulling on fixed normal bars for
additional pedal power without overloading their heart and lungs.

The concept of linear pedal mechanisms and the like is a discredited
belief of people who do not recognize reality. Bicycle riding has
been scrutinized for more than a century and nothing new and useful
has come up since the beginning of the chain driven bicycle.

The most efficient pedaling is the technique that enables you to
apply very effective power to the pedal from 11 to 5 'clock
regardless of what your cadence is because this enables you to use a
higher gear for the same effort of a rider who does not have this
technique. The pulling up is done by the arm not the leg.

I think you are mistaken. Go row a bit and observe what occurs. The
bicyclist ha no lack of transmitting power but rather a limited
aerobic capacity, and nothing will get past that. you seem to believe
that power can be extracted from muscles without them demanding oxygen
and glycogen. I think you ignore that the first measurement of
interest by a bicycling team is lung capacity, not muscles or pedaling
style.

The explanation for the ineffectiveness of PowerCranks is that the
pulling power of the leg is only effecive at a low cadence or when
out of the saddle and even then can only be used for short periods.

Not at all. The problem is that lifting the leg against gravity is
work even without adding any torque. On normal cranks the legs are
balanced and require no effort to go around, up or down.

Let's not overlook that with conventional cranks, the feet an legs
are balanced and that it take no effort to rotate the cranks
forward, clipped in and with non chain. With Power Cranks, this
takes considerable effort, the feet not balancing each other.

If you were pedaling for most benefit, the feet would not be
balanced as you should be unweighting the idling pedal as soon as
you stop applying the power, making the most out of the assistance
of gravity. In that one instance PowerCranks could prove to you the
error of your ways.

Why "should" I be unweighting the "idling" pedal? That makes
unnecessary work that I can do without. This work is better done with
the descending leg. Invoking other muscles to do this is inefficient.
That the downward pushing muscles have the ability to do this is amply
demonstrated and that there is reserve is demonstrated in sprints that
use up the aerobic capacity. You are suggesting that there is an
inefficiency in the principal muscles we use to propel ourselves and
engaging other unnatural muscles improves power generation. I don't
believe a word of it.

The limit of climbing hills or flat TT depends on aerobic
capacity. That is what good bicycle racers have that others don't.

True but knowing how to get the most out of your pedals and cranks
can help you to make the most of your aerobic capacity.

You think you can fool the muscles into doing free work.

Jobst Brandt

On Sun, 05 Oct 2003 03:49:50 GMT,
wrote:


Anyone who has not trained with these cranks cannot ride with them,
the requirement to keep positive forward torque on both cranks
throughout rotation is difficult to accomplish.

That's the point. These cranks are not marketed as being faster than
normal cranks. They are marketed as a training tool, so that when a
rider who uses them a lot rides on a bike with normal cranks, he/she
will be more powerful. I'm not sure I believe that though.

JT
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RE/
Engaging more muscles
in propelling the bicycle burdens the heart and lungs with the
overhead of more muscles rather than using the principal ones that are
naturally used.

Does that supply me with a rationale to not learn how to spin?
--
PeteCresswell