From: jbrandt@hpl.hp.com (Jobst Brandt)
Newsgroups: rec.bicycles.tech
Subject: Re: Spinning
Date: 9 Jul 2000 03:27:29 GMT

Jim (who?) writes:

> I've read and heard enough from my friends about spinning to believe
> it must be the best way to have both endurance and speed (have cake
> and eat it too).  I naturally tend to pedal a bigger gear
> combination than a "spinner" would and have decided to give change a
> try.  Is the theory that less pedal force saves the leg muscles for
> going longer distances and the drop in speed is offset by faster
> spinning which requires better aerobic and cardiovascular
> conditioning?

Just as in walking, everyone has a stride and walking with
artificially short or long stride (low or high cadence) is a detriment
to effective propulsion.  That doesn't mean that once in good
training, a rider will not ride a different cadence than when first
starting to ride.  Besides, cadence also depends on the effort being
expended.  Just cruising along at 15mph enjoying the scenery is
diminished by consciously riding a gear other than the one that feels
the most comfortable.

The argument that you must spin to save your knees is true for the
fewest riders.  I have not yet discovered how these riders climb hills
consistent with this constraint, because when climbing, pedal pressure
is greater and extends over a larger arc of the pedal stroke than any
flat land riding.  It is essentially a deeper knee-bend, the essence
of this contention, than riding on flat land at slow cadence.

Over many years of touring in the Alps and Sierra Nevada, I have not
seen anyone spin after the first half day, no matter what they
espoused beforehand.  Most of the spin coaches are theoreticians who
would most likely pack up or change their tune on a ride where they
were not riding a gratuitous style over an insignificant distance.
I'm sure people can cite exceptions but I have not seen them.  If you
want to know what kind of rides I mean, you can review some at:

http://www-math.science.unitn.it/Bike/Countries/Europe/#Jobst

> Would like to know the experiences of other's that have gone from
> where I am to being good spinners.

That depends on why and where you ride your bicycle.  I do it for fun
and to experience the out doors, others like to do it on a treadmill
or in the midst of a pack and get a certificate of completion.  Not
everyone has the beautiful landscape that my SF Peninsula and Santa
Cruz mountains offer.  That may be a factor in what you do.  But don't
feel you must make an uncomfortable task of riding just so that others
don't criticize your choice of gears.  I've heard enough of that from
people that I have passed on bike rides and tours.

http://www.bicyclinglife.com/Recreation/SierraSpring.htm

Jobst Brandt      <jbrandt@hpl.hp.com>

From: jbrandt@hpl.hp.com (Jobst Brandt)
Newsgroups: rec.bicycles.tech
Subject: Re: Spinning
Date: 10 Jul 2000 00:25:44 GMT

Peter Headland writes:

> Can you define what you mean by "spin" here?

Any speed that you would not naturally use but would pursue because
"it's better for you".  That goes especially for cadences above 100
that are probably in themselves unnatural acts for anyone who isn't
racing.  It's much like the .com folks who drive down the main in
their $porty car at 5000+ RPM because its a fast car and you should
notice it.  There is no reason to run an engine at partial load near
the red line on the tachometer and the same is true for bicycling.

> My natural cadence is around 90-95 rpm.  Not something I think
> about, just the way I ride naturally.  If I go much above 105rpm for
> any significant period of time, I find it very tiring (I use this as
> CV training when I can be bothered).  When I was younger (1970's)
> "twiddling" was regarded as 90rpm (and I was bang-on the fashion),
> but it sounds like "spinning" might mean something faster?

You ought to ride that gear that you naturally choose for your own
comfort.  None of these guys are racing and I'm sure they don't
average over 15mph on a 100 mile ride.  Remember, the TdF averaged over
25 last year.  That's racing but even they don't climb long hills at
more than about 80 RPM.  You can watch the videos in your local bike
shop.  Of course they sprint at far higher speed but that's sprinting
and you needn't emulate their speed while twaddling along.

Jobst Brandt      <jbrandt@hpl.hp.com>

From: jbrandt@hpl.hp.com (Jobst Brandt)
Newsgroups: rec.bicycles.misc
Subject: Re: Why 80 - 100 RPM
Date: 13 Jul 2000 14:47:29 GMT

Brian Vanley writes:

> I'm new to the cycling world and I'm curious as to why someone
> should try to sustain 80 to 100 RPM while spinning.

You probably shouldn't, that is, not until you develop your bicycling
fitness to the point where this becomes easy and preferable.  On the
other hand, if you are riding slowly there is no point in higher
cadence.  Basically, experienced riders ride about the same gear on
flat land regardless of speed, and therefore, ride a large range of
cadences, while pedaling faster the harder they are working.  This
becomes more evident in time trial riding, where one generally tries
to maintain a speed of 25mph for one hour, the classic 25 mile TT.

TT riding is not as popular as it once was but it is one of the best
introductions to developing pedaling rate and endurance, both for
recreational riding and racing.  If you are in a club that has such
events, participating should resolve your question by itself.

Jobst Brandt      <jbrandt@hpl.hp.com>

From: dblake@popper.ucsf.edu (David T. Blake)
Newsgroups: rec.bicycles.tech
Subject: Re: Spinning, and shifting to "diesel mode"
Date: 12 Jul 2000 15:55:46 GMT

Doug Milliken <bd427@freenet.buffalo.edu> wrote:
> Anyone watch Lance yesterday (Stage 10)? His cadence when
> climbing is typically a lot higher than most of the others in the
> Tour (at least the ones that the ESPN2 coverage shows). I noticed
> the same thing last year in the Tour. Over the winter, I saw an
> interview (or article) with Chris Carmichael(sp?), Lance's coach
> in Outside magazine -- he made the point that he had Lance
> training to do high cadence while climbing...sure seemed to work
> yesterday!
>
> On 10 Jul 2000, Jon Isaacs wrote:
> > >output, why is it that we all go into the "diesel mode" when the road
> > >shoots up?
> >
> > I have also pondered this point. A while ago I produced an
> > explanation based on something I saw posted here, ie that oxygen
> > consumption is most efficient at about 60 rpm.

Most efficient doesn't cut it for racing. Fastest does. You are
fundamentally limited by cardiac output while climbing near
anaerobic threshold. Faster cadence provides more blood flow back
to the heart, which boosts cardiac output. The heart is
exceedingly sensitive to venous return. This allows higher heart
rates to be sustained, and greater power output. It only works if
you are trained to be reasonably efficient at higher cadences.

An analogous effect allows triathletes to sustain higher
heart rates running rather than cycling.

So whereas oxygen consumption is most efficient at 60 RPM,
high efficiency wrt oxygen doesn't cut it. Low cadences are
not for tour racing, sprinting, or hour records. Dieseling
is just fine if your primary concern is not absolute speed.
Most people are a lot more comfortable dieseling up hill
rather than spinning.

--
Dave Blake
dblake@phy.ucsf.edu

From: dblake@popper.ucsf.edu (David T. Blake)
Newsgroups: rec.bicycles.tech
Subject: Re: Spinning, and shifting to "diesel mode"
Date: 13 Jul 2000 17:04:11 GMT

Tim McNamara <timmcn@mr.net> wrote:

> I will confess myself confused as to why someone with a high
> percentage of fast twitch fibers would climb better at lower
> cadences.

> Perhaps someone with knowledge of physiology can clear this up
> for me.

Fast twitch fibers fatigue with fewer repetitions, as they have
less mitochondria. They recover slower. At higher and higher
cadences, you rely on the muscle fibers with more and more
ability to use oxygen rapidly - slow twitch fibers.


--
Dave Blake
dblake@phy.ucsf.edu

From: dblake@popper.ucsf.edu (David T. Blake)
Newsgroups: rec.bicycles.tech
Subject: Re: Spinning, and shifting to "diesel mode"
Date: 13 Jul 2000 22:27:45 GMT

Eric Salathe <salathe@atmos.washington.edu> wrote:

> Most long grades are only 6%, which is horizontal as far as the
> gravitational vector on the body, so why must the biomechanics change?

There is a change in the force:velocity relationship duty cycle
climbing compared to riding flats. On flats, the wind resistance
is close to constant enough that pedalling very unevenly has no
penalty.

On the hills, it is quite to the contrary. Smooth pedalling
leads to nearly constant velocity and acceleration up the hill.
The pedals actually push back at you during dead spots in
climbing. The force on the pedals is proportional to the
velocity. The requirement of a minimal pedalling force through
the dead spots is significant - especially on steeper climbs.

You can easily see that people who do not train in the hills
might very well be poorly adapted to climbing, and assume a very
different pedal stroke.


--
Dave Blake
dblake@phy.ucsf.edu

From: dblake@popper.ucsf.edu (David T. Blake)
Newsgroups: rec.bicycles.tech
Subject: Re: Spinning
Date: 14 Jul 2000 01:44:59 GMT

Jobst Brandt <jbrandt@hpl.hp.com> wrote:
> David T. Blake writes:

> > In cadence, there is a fundamental tradeoff.  You lose leg power
> > at higher cadences and gain cardiac function.  At some cadence you
> > reach the point of diminishing returns - because leg function
> > falls off too rapidly to be balanced by increased cardiac output.
>
> As we have often discussed here, climbing hills is not like riding the
> flat because the required duty cycle (muscular stroke) on hills,

See my other post today on duty cycles and hills vs flats.

> ... A long power stroke requires a long recovery cycle and
> this precludes high cadence.

I agree if you start with the presupposition that you are
taking riders trained on flats and subjecting them to
hills. Of course we normally ride both, and the shorter
recovery periods can be adapted to IF one chooses to train
by riding hills with high cadence.


> > In short, as cadence increases above 60 RPM, you become less
> > efficient, but able to put out more continuous power.
>
> I don't see how you can support these two conflicting concepts.
> There is an aerobic limit and less efficiency gets you to it more
> quickly.

The point is that increased cadence allows higher heart rates.
This can be verified by anyone with a heart rate monitor, if they
do a 5 minute time trial at 60 RPM and repeat at 120 RPM (with
SOME training at each cadence a priori). The 120 RPM time trial
will always result in a higher sustained heart rate. The faster
cadence makes the heart more mechanically efficient, even if it
decreases the leg's efficiency (wrt oxygen usage). These factors
combine to determine best cadence for maximal power, and often
people feel like they can sustain higher heart rates longer with
higher cadence. They are less efficient, but faster.

A similar set of effects allows most people to sustain higher
heart rates running than cycling. Running returns more blood to
the heart - therefore the heart can pump more efficiently (wrt
mechanical considerations).


> I don't believe it is as mysterious as you make it sound. The
> true test is to measure against other top riders and see who
> consistently achieves better results.

You can spend a month or so acclimatizing to high cadence
climbing and do your own tests. I know what mine are. I suspect
people more "fast twitch" oriented will not do well at cadences
as high as those I use. This is a factor of recovery period, as
you note.


--
Dave Blake
dblake@phy.ucsf.edu

From: jbrandt@hpl.hp.com (Jobst Brandt)
Newsgroups: rec.bicycles.tech
Subject: Re: Spinning
Date: 14 Jul 2000 21:20:36 GMT

David T. Blake writes:

>>> This can be verified by anyone with a heart rate monitor, if they
>>> do a 5 minute time trial at 60 RPM and repeat at 120 RPM (with
>>> SOME training at each cadence a priori). The 120 RPM time trial
>>> will always result in a higher sustained heart rate.

>> The question of heart rate is interesting but what about the
>> question of speed? Is the speed in these two tests a constant?

> No. The rider is faster at higher cadences. It merely requires
> a moderate amount of training at the cadences involved.

So how fast is fast enough and what is too slow?  This seems to be
relative and I don't see to what it is referenced.

>> What happens to the heart rate if the speed over the 5 minute time
>> is a constant, does this result in a lower heart rate at 120 rpm?

> I'd suspect marginally lower, perhaps difficult to measure accurately.

I've watched many hill climbs both in person and on video, and I don't
see a lot of correlation between what the experts here say and what
the experts on their bicycles do.  It is not machismo that chooses the
gear.  I am certain of that.

>> Personally I would choose a cadence that gave me the lowest heart
>> rate for a given speed. Is this wrong??

> It depends on your goals.  If you fix the speed and optimize for
> heart rate you are not really trying to go fast anyway.  If you
> maximize speed over some course by whatever heart rates you can
> sustain, you are racing.  In mountain racing you can immediately
> tell a rider has lost his legs when his cadence goes.

How about optimizing speed.  I think that is what most people do in
touring and competition.  The rest is sophistry.

> Of course there are many people not trying to maximize speed,
> and they should choose whatever cadence suits their goals.

I don't believe so.  They may not be optimizing physical output and
exertion, but they are using the gear that gets them the best speed at
that level of exertion and I think that is being ignored.

Jobst Brandt      <jbrandt@hpl.hp.com>

From: dblake@popper.ucsf.edu (David T. Blake)
Newsgroups: rec.bicycles.tech
Subject: Re: Spinning
Date: 15 Jul 2000 01:14:16 GMT

Jobst Brandt <jbrandt@hpl.hp.com> wrote:
> David T. Blake writes:
>
> >>> This can be verified by anyone with a heart rate monitor, if they
> >>> do a 5 minute time trial at 60 RPM and repeat at 120 RPM (with
> >>> SOME training at each cadence a priori). The 120 RPM time trial
> >>> will always result in a higher sustained heart rate.
>
> >> The question of heart rate is interesting but what about the
> >> question of speed? Is the speed in these two tests a constant?
>
> > No. The rider is faster at higher cadences. It merely requires
> > a moderate amount of training at the cadences involved.
>
> So how fast is fast enough and what is too slow?  This seems to be
> relative and I don't see to what it is referenced.

I suggested a simple test anyone can do. I can ride fastest for
5 or 10 minutes on the flats with a cadence around 115 RPM. But this
only happens when I've been training with high and low cadences, from
60 to 120 rpm. I climb fastest at only marginally slower cadences.
But again, this only works with adequate climbing training at
higher cadences. The differences are NOT small wrt race placings,
at least in my case.

As I pointed out, there is quite a good physiological justification
for higher cadences wrt efficieny of the heart. One can note that
optimizing for speed in an hour still results in fastest heart
rates around 110-115 RPM. Some people are better even higher than
that.

--
Dave Blake
dblake@phy.ucsf.edu

From: dblake@popper.ucsf.edu (David T. Blake)
Newsgroups: rec.bicycles.tech
Subject: Re: Spinning
Date: 14 Jul 2000 13:52:53 GMT

Jon Isaacs <jonisaacs@aol.com> wrote:
> >The point is that increased cadence allows higher heart rates.
> >This can be verified by anyone with a heart rate monitor, if they
> >do a 5 minute time trial at 60 RPM and repeat at 120 RPM (with
> >SOME training at each cadence a priori). The 120 RPM time trial
> >will always result in a higher sustained heart rate.
>
>  The question of heart rate is interesting but what about the
>  question of speed? Is the speed in these two tests a constant?

No. The rider is faster at higher cadences. It merely requires
a moderate amount of training at the cadences involved.



> What happens to the heart rate if the speed over the 5 minute time is a
> constant, does this result in a lower heart rate at 120 rpm?

I'd suspect marginally lower, perhaps difficult to measure accurately.


> Personally I would choose a cadence that gave me the lowest
> heart rate for a given speed. Is this wrong??

It depends on your goals. If you fix the speed and optimize for
heart rate you are not really trying to go fast anyway. If you
maximize speed over some course by whatever heart rates you
can sustain, you are racing. In mountain racing you can immediately
tell a rider has lost his legs when his cadence goes.

Of course there are many people not trying to maximize speed,
and they should choose whatever cadence suits their goals.


--
Dave Blake
dblake@phy.ucsf.edu

From: Dave Blake <dblake@popper.ucsf.edu>
Newsgroups: rec.bicycles.tech
Subject: Re: Please explain crank length theory?
Date: 30 Sep 2001 16:49:02 GMT

Phil Holman <philjud@earthlink.net> scribed:
>  Here are the actual results of the test
>   Cadence        Heartrate        Power External
>
>  60              96              150W
>  75              100             150W
>  90              105             150W
>  105             112             150W
>  120             132             150W
>
>  You can search in Google for the whole thread "Cost of Pedaling versus
>  Cadence"

Congratulations. Starling and Guyton would be proud.

Higher cadences push more blood back to the heart, so cardiac
output goes up.

Leg efficiency, especially if you haven't trained at high
cadences, will be less efficient for the legs. So you get more
work from the heart, and less per revolution from the legs.

If you train at high RPMs I expect the difference will decrease.

But first try this test. Take a fixed course, and race it at
constant RPMs. Ignore wattage - just race the fixed distance
pushing as hard as you can at one cadence. Then, after
recovering, do it at different cadences. For most people such
races over reasonably short distances find >100 cadence is best.

And do not be misled by your numbers. Higher cadences improve
cardiac efficiency, and decrease leg efficiency. As I
mentioned, the leg efficiency can be improved from high cadence
training. All hour record attempts are made at cadences from
105 to 125 - because this allows the highest speed. Leg
efficiency is usually highest closer to 60 RPMs, and without
training at higher RPMs will stay there.

--
Dave Blake
dblake@phy.ucsf.edu