- When it comes to cycling technique,
one question seems to endure above all others.
When climbing, should you pedal faster
if you want to go faster?
I mean, spin to win, right?
It's the secret of the pros.
And therefore, if you want to go faster,
you need to practice pedaling faster.
And, in fact, this style just won
on the fearsomely steep Monte Zoncolan
at the Giro d'Italia this year.
Although in that particular context,
we have to use the term style quite loosely.
But is it actually faster?
See, I'm not entirely sure that it is,
even though the pros do it.
So we're going to explore the issue
and just so that it's not a load of scientific chat,
we've also devised a short,
extreme and incredibly painful test
involving me as the guinea pig.
(fast paced techno music)
For the purposes of this video,
we're going to call spinning 90 rpm and above
and grinding 80 rpm and below.
And we'll completely gloss over that a bit in the middle
which is kind of just pedaling.
And the test that we're going to do.
Well, we've got two runs.
Firstly, a 34/28 and then with a quick swap
of the crankset to 39/23.
A very old school gear,
what I used to race on in fact.
And our test climb is not an Alp,
it's not a Rocky Mountain,
nor is it a Dolomite, although thank goodness.
Monte Zoncolan looked absolutely horrible.
But nevertheless, it is a little hill
in a quiet corner of England,
but it is still particularly nasty.
It is super steep.
The kind of climb where you can take
your functional threshold power,
screw it up, and throw it out the window.
First up, 34/28 spinning
and hopefully winning.
(lively rock music)
So while I desperately labor up this horrible climb,
what are the reasons for spinning
and why does it have such a following?
Well, it's certainly indisputable physics
that a high cadence requires less torque,
so you push the pedals with less force for a given power.
And one might imagine then that spinning
helps to do less muscle damage.
For a time, it was also thought that spinning
a faster cadence, paradoxically perhaps,
would use a greater proportion of
efficient slow twitch muscle fibers
compared to slower high force pedaling,
which relies on fast twitch.
And some studies have shown that low cadence pedaling
sometimes uses more muscle glycogen.
So essentially, you might blow quicker if you pedal slower.
However, it is not that simple.
That fact would only be relevant anyway
when pedaling at close to your maximum.
Most research has shown that riders with
a greater proportion of slow twitch muscle fibers
are more efficient at lower cadences.
(breathes heavily)
That was absolutely horrible.
(breathes heavily)
That's not my normal style, that.
Couldn't get out of the seat.
I was pedaling too fast.
(breathes heavily)
Yeah, I'm surprised if that's quicker for me.
Heart rate hit 190 today, always a good sign.
There is a reason why pedaling fast
can feel so uncomfortable.
Some recent research demonstrated just how much energy
goes in to simply moving your legs up and down.
And energy cost that you could imagine is only magnified
if your ankles are as heavy as mine.
Now the faster you pedal,
the more energy you expend on that movement.
So at lower power outputs,
the majority of your energy could simply be
on lifting your legs up and down.
And then the faster you pedal then,
the more energy you will need to spend simply on movement.
So at lower power outputs, you could imagine
that actually most of your total energy
goes into simply turning your legs around.
But then as your power increases,
the proportion of that energy as a relation
to your total energy expenditure,
therefore decreases.
Now initially that research was not carried out
on trained cyclists.
But some of it was.
In fact, probably some of the most important
research on this subject,
it took place in the late '90s.
And that showed that as your power output increases,
the effect of your cadence on your efficiency
does indeed diminish.
So more power means that you can,
therefore, pedal faster.
Perhaps explaining why pros do what they do.
But maybe they pedal fast, because they go fast.
And not the other way around.
Anyway, that's probably enough procrastinating.
I've got another run to do.
Run number two.
If anything I'm kind of looking forward to this,
old school slow pedaling malarkey.
Lactate clear from the legs,
100 percent commitment.
You ready?
Okie-doke.
(upbeat music)
80 rpm and out of the saddle, normally.
The basic discussion of cadence shows
that there is a relationship
between power output and pedaling rate.
I.e., faster riders are also likely to pedal faster.
But does that change when climbing?
Now, research, including some by
the legendary coach Fred Grappe,
demonstrated a long time ago that
the way we pedal changes when going uphill.
Even when you control for cadence.
Because we change how our force is distributed
over the pedal stroke.
And it's true, that for the majority of the pro pelaton,
the pedaling rate does decreases when climbing,
despite an increase in power output
compared to flat riding.
We can also see from the data, from Velon,
at the Giro d'Italia, that climbing does affect cadence.
In a time trial, Tom Dumoulin will pedal at 100 rpm,
on Monte Zonoclan, it was just 80 rpm.
So what is going on?
(breathes heavily)
We'll do the results from here.
So that was five minutes of fairly extreme pain.
Has it demonstrated anything?
Well, both hurt.
Both have giving me burning legs and searing lungs.
But I think perhaps the only thing it's going to demonstrate,
to you, is what my prefer cadence is.
And that is because I went quite significantly faster
on run number two where I was pedaling slower,
but my power output was also higher.
Now my average heart rate was also two beats a minute lower,
but I'm loathe to read anything too much into that.
But as our extremely scientific experiment,
with a data pool of one,
successfully proven anything then?
Well, no.
Clearly not.
But what it has done, is reiterate the fact
that everybody has a preferred cadence.
Now, we will automatically defer to our
most efficient cadence if we're left to our own devices
and we've also got the gearing options available to us.
Now what your preferred cadence is,
is going to depend very much on your muscle fiber type
and your leg length proportions, and your crank length,
perhaps, even yes,
the weight of your ankles.
And, of course, remember
that your pedaling cadence isn't fixed over time either.
You might find that actually you pedal faster
at the beginning of a ride compared to the end of your ride.
And on this particular case, yes,
a slower cadence allowed me to try harder,
so I got up the hill faster.
But that's not going to be much good
when we're on Monte Zonoclan.
Anyway, the picture is still frustratingly muddy,
so I think we need to defer, once again,
to our genie-us.
- Professor Louis Passfield.
Louis, I'm going to get straight in there.
Why do riders tend to pedal slower when they're climbing?
- That's a great question, Simon.
I wish I could give you a very definite answer to that
and it's something that still always
the topic of conversation.
Over a cup of tea, after a ride.
- [Simon] (laughs) Yeah.
- And even over a cup of tea amongst scientists.
So at the University of Kent,
we've done quite a few studies looking at riding uphill
and trying to figure this one out ourselves.
- Okay.
- What I think we can say is that
we know as you ride uphill, the gradient shifts.
And actually that changes how you pedal a bicycle.
- [Simon] Okay.
- [Louis] So instead of where you press down
normally when you're riding on the flats,
it becomes a different place when you
tilt the bicycle uphill.
So that's one thing about how your technique changes.
- [Simon] Okay.
- [Louis] And then you're also fighting
gravity when you go uphill.
Whereas on the flat, really gravity isn't
having a major effect.
- [Simon] Yeah.
- So it changes the way that the bike,
the forces on the bike, are resisting you.
Or what you're working against.
- [Simon] Okay.
- So we know from studies now,
for a quite a few years, that the pedaling technique,
if you're to look at the forces on the pedal,
they change as you go uphill.
When riders start pedaling uphill,
they change the way they pedal.
- Okay.
- To take advantage of the gradient.
And that's what causes them to slow down
and change their pedaling technique.
- So, now I don't know if this is what you were trying
to refer, but does that mean, therefore, actually
that pedaling slower is more efficient for those riders
or does it mean that it's only more efficient
when gravity is adding that extra force
into the equation of making your bike go forwards.
- So I'm thinking specifically about
the effect of gravity as you're riding uphill
as opposed to the difference between riders.
So I'm taking the fact that there's a difference
between riders as a given, if you like.
- Yeah.
- And there's a whole host of different factors
that will determine what the most cadence,
what the most comfortable cadence is for you.
But once you go uphill,
gravity is working on everybody in a similar kind of way,
and it's shifting their technique in a similar kind of way.
And that's part, part of the equation probably.
- Okay.
So if a rider does choose to pedal more quickly,
like say Chris Froome or Lance Armstrong,
probably the two most famous examples
of riders with faster pedaling rates when climbing.
You know, what are they doing differently,
other than the obvious,
which is just pedaling faster.
Is there anything on the kind of physiological level
that you can determine that's different?
- Well, they would definitely had to have done quite
a lot of training in order to
be quite comfortable with riding uphill
at that kind of cadence.
And I suspect that what that really means is
they're more efficient at that cadence
and that's the consequence of a lot of training,
a lot of practice.
It wouldn't happen overnight.
It wouldn't happen even just a function of them
being super fit cyclists.
They probably had to practice that over considerable
length of time in their training for many years.
The other factor to consider as well is
because they're pedaling that quickly,
they probably don't get out of the saddle very often.
- Yeah.
- So I haven't studied that specifically
by looking back at old race footage.
But anyone out there could.
- Yeah.
- And I suspect you'll find that they
don't get out of the saddle very often.
Now, if your preferred style of climbing is to mix
sitting in the saddle and getting out of the saddle,
you're not going to be able to get out of the saddle easily
at those really high cadences.
- [Simon] No.
- So part of what you'll probably see is those people
that prefer to pedal a little more slowly,
also like to mix it up in terms of
how much they get out of the saddle
and move between in and out of the saddle.
Whereas, people like Froome and Armstrong previously,
probably stay in the saddle an awful lot more
than those other riders.
As I said, it's a consequence of their training,
the practice that they've done to do that.
- So, so, whoever coached Lance, whoever coaches Froome,
they've obviously suggested that they practice this.
Is that part of the reason why
they can go uphill as fast as they can?
Is it something that more riders should train?
- Um, it could well be a useful thing to train.
But I think it's probably most beneficial
for stage race riders.
Because part of what they may well be doing is
benefiting from making that effort
somewhat less damaging for them.
Not necessarily on one day,
but over several days.
When you add that effect up,
over many, many days during a stage race.
And of course, those really hard climbs are likely
to be the crucial race deciding moments too.
So you take those two things into account,
pedaling a little bit faster reduces
the forces on the muscles,
which may, in turn, make the ride
that little bit less damaging.
Makes it easier to recover the next day
and do the same thing again on the next climb
the following day.
- [Simon] Yeah.
- [Louis] So that is probably why they're doing that.
If you're a rider that wants to go uphill fast,
you don't necessarily need to learn
to pedal quickly doing it.
- [Simon] Okay.
- For example, with James Hopker at the University of Kent,
we did a study with one of our research students
where we compared riding in the saddle with out of saddle.
Sorry, out of the saddle and in the saddle.
And what we found there was that
there was a difference in how efficient you were,
in the saddle compared to out of the saddle.
In the saddle, you were more efficient
than you were out of the saddle.
But only at low intensities.
So let's say the first few climbs of a
big mountain stage in the Tour.
- Yeah.
- Or the Vuelta.
Whichever race we're thinking about.
The Giro, at the moment.
There, if you're out of the saddle,
and you're not working particularly hard,
because it's early on in the race,
that's less efficient than sitting in the saddle.
- [Simon] Okay.
- Once you start working harder, the situation changes.
And actually getting out of the saddle
becomes as efficient as staying in the saddle.
So it's not an advantage to get out of the saddle,
but you lose the disadvantage once you start working harder.
So the two actually come closer together.
- Okay, right.
Now, we've been talking about professional cyclists
from the draw to this.
What about, you and I?
The normal rider.
You would put out less power,
should we be pedaling faster,
trying to train ourselves to pedal faster,
or should we say, right, lower power,
it's more efficient to pedal more slowly,
that's what you should do.
- I think you'll find for the average rider like ourselves,
as we work harder, going up a climb,
assuming we're actually fit enough to change tempo.
(laughs)
Then, I would say your cadence would naturally
rise one or two revs anyway.
- [Simon] Okay.
- And if you were in training,
it wouldn't do any harm to try to raise it
another two or three revs,
to just start to tease your body with the idea of
working a little bit harder,
at a slightly higher cadence than your body
naturally wants to do.
But I wouldn't spend an awful lot of time practicing
that in the way that someone
like Armstrong of Froome would necessary.
Because I think the real benefits that would come
over really sustained practice,
many, many sessions, many hours,
and the benefits of that would pay off in a stage race,
rather than just on the next climb you happen to go up.
- You know I don't why we didn't just interview Loius
and then save myself all of that hard work.
But, never mind.
It is always good to experiment with your riding
and actually work out how you respond to
different pedaling rate.
And remember as well, that even if you choose to ride
at a certain cadence naturally,
it doesn't mean that actually you wouldn't benefit
from training at different cadences.
Slow and fast.
Now do remember to give this video a big thumbs up.
Say thank you very much to Louis.
And if you want to see some more of his genie-us tips,
then click just down there.
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