Ken Roberts
Lots of skaters could be much more effective in using heel-brake for
slowing and stopping, if they understood better how to make it work.
Who this page is for:
- Inline skaters who get out to skate for exercise or to go some
place, and
- whose skates came in their box with a heel-brake already
attached as the standard assembly configuration from the
manufacturer:
Keep reading below on this page.
Other kinds of skaters and skates -- see other pages:
- instructors, or
- people who want the underlying theory:
See analysis page describing all
the different methods.
- racers or speedskaters, or those
- whose skates did not come in their box with a
heel-brake already attached as the standard assembly
configuration from the manufacturer -- skates where the
heel-brake can be attached as a separate option:
See the page for skates not
specifically designed for heel-brake stopping.
- hockey, dance, jumps, tricks, grinds:
Find some other source of information about stopping
-- perhaps
among these resources for
learning -- since we
don't know much about those kinds of skating.
Why not?
See below.
Not sure if you're getting a quicker stop? Then
you're probably not.
?? General recreational skates ??
see photos of examples.
?? Other kinds of skates: hockey,
speedskates, freeskate - FSK - aggressive, dance.
This straightforward method is
called Method C.
?? name of method, 5-word
description.
Usually it delivers stopping force about three
times stronger than the obvious way.
Method C is a special skill and does require some balance and
some practice.
It is possible that some skates that
satisfy those criteria above do not enable effective stopping
by using Method C. For how to tell more accurately if some pair of
skates supports Method C, [ see the C test ].
A good instructor can help provide a safer
environment and learning approach, check if your skates and heel-brake
are appropriate for your needs, and help find ways around hang-ups and
confusions.
How find an instructor? see below.
Don't think that effective stopping
should require learning new skill and balance? see below for
alternatives.
[ Rollerblade ABT ]
[ Riding a bicycle provides exercise while
without much more skill required for stopping than for riding -- and a
foldable bicycle is almost as convenient to take inside buildings or on
trains as a pair of skates. ]
see also
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I am not an instructor. I'm a skater who has tried
some different heel-brake designs and different heel-brake (and
non-heel-brake) stopping methods -- and who knows the relevant physics
pretty well, and has put some work into analyzing how the structure of
heel-brake design and skate + frame + brake configuration work to stop a
skater.
Skaters who want to learn something this important for
not getting hurt, should learn it from someone experienced with the
tremendous fascinating complexity of helping real humans succeed in trying
new actions -- an insightful and experienced human instructor (not just
from reading
some words on a web page based on physics).
Most people find that it's pretty easy to make a
bicycle stop in a quick and predictable way, by squeezing the brake
lever with their hand (if it's a hand-brake), or by pressing their foot
in the correct direction on the pedal (if it's a pedal-brake). The only
skills or balance needed is to know which lever (or pedal) to press in
which direction, and to not lean forward so their head doesn't fall
forward onto the ground when the wheels stop.
Seems like with skates, if somebody knows to press the
heel-brake downward against the ground, and to lean their head and
shoulders back a little, they ought to get a quick and predictable stop.
But for most people learning to skate, that's not how it works. Instead
they come to a stop only slowly.
Most bicycles are usually easier to stop quicker
because:
-
most bicycles have multi-part mechanisms with
levers and cables to magnify and transmit the braking force applied
by the rider's muscles.
-
the human muscles used to apply braking force on a
bicycle, such as fingers squeezing a lever (or foot pressing down on a
pedal), are muscles that practice their strength often in other similar
moves performed in many other activities of normal living.
But most inline skates provide little magnification of
braking forces applied by the rider's muscles, if the rider's body
and legs are in an obvious normal standing or skating-propulsion position.
And the usual human muscles for the obvious heel-brake move (e.g. pulling up
with the top of the front of the foot) do not get much
strengthening-practice in other activities of normal human living.
How come skates aren't designed to make it easier?
Which raises the question: How come most inline skates
don't come with some clever multi-part mechanism that magnifies the muscular
force, or enables stronger muscles to be applied?
Actually several clever mechanisms like that have been
designed and manufactured and sold -- though some of those mechanisms do not
work as well as others, and some have disadvantages.
But most inline skaters (including me) still purchase
skates without such mechanisms. Different skaters haver different reasons.
Here's my reason:
If I just wanted something easier to use without learning
any new skills, I'd just ride my bicycle. I skate because it's magical, not
because it's easy. And because skates allow me to "show off" my ability to
learn new skills and new kinds of balance.
When I bought my first pair of skates, I was expecting
to be learning some new skills and balance. I did not know then that braking
was going to have to be one of those new skills. But on most "general
recreational" skates (with good concepts and a decent instructor), the skill
and balance for quick braking is not more difficult to learn than lots of
other skating things. So I was glad to learn it, and then glad to purchase
more skates that also required skill and balance for braking.
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??
concept of this Method
The fundamental idea is to press the brake pad down by
pressing the back of the lower leg backward against the inside of the
back of the high boot stuff -- and to get the force to press the lower
leg backward mostly from the skater's body weight.
Most of the skater's body weight is not in
attached rigidly to the lower leg, so much of the force must be
transmitted through the knee joint. Which means that muscles must be
used to hold the knee joint rigid. Those muscles are the knee-extension
muscles (e.g. "quadriceps") -- which are among the biggest strongest
muscles in the human body. And the knee extension muscles don't have to
move, they just have to hold rigid ("isometric") -- which is the mode in
which they can apply their largest force. So these muscles are good
candidates for this task.
There's a trade-off here in the physics, because
pressing the lower leg down and back (which transfers weight off from
the wheels of the front skate onto the brake pad) also tends to move the
weight of the buttocks and upper body down and back -- which tends to
transfer weight off from the brake pad and backward onto the
rolling wheels of the rear skate.
So a key tip is to keep the knee joint of the braking
leg extended straight -- to maximize the force against the inside back
of the boot cuff without any extra movement of the hip down and back. It
turns out that the amount of motion of the hip down and back is still a
rather large -- but as long as the greater gravitational leverage is
being transmitted thru the knee joint to the lower leg pressing back,
then it's worth it. On the other hand if the weight of the buttocks and
upper body further back is mostly supported by the rear skate, then
dropping the hip further back is not worth it.
Since it takes (isometric) strength in the
knee-extension muscles (e.g. quadriceps) to transmit the force of body
weight into braking, skaters with less strong leg muscles might not be
able to achieve the same tranmission of body weight, and so might not
achieve as high an intensity of braking force.
How far to drop the knee + hip back? There's a minimum
needed just in order to move brake pad into contact with the ground and
press the back of the lower leg into full effective contact with the
inside back of the boot cuff to transmit significant force. Basically
that's the critical angle + position. Applying more force compresses the
foam in the inside back of the boot and the body tissue in the back of
the lower leg a little more, which allows the knee and hip to move back
a little farther. If press harder and drop the knee and hip lower,
perhaps could get the rear wheel of the braking skate up off the ground.
Why this Method is stronger: because it uses stronger
muscles -- big leg muscles -- which get frequent practice when walking
and lifting things.
Techique levels of this Method:
-
The "Basic" level technique for this Method is to
learn to apply substantial force thru the brake pad and remove
substantial weight from the rear wheel of the braking skate (the
front skate).
-
The "Enhanced" level technique is to transfer
substantial weight from the non-braking skate (rear skate) to the
brake pad (but without putting more weight on braking skate's rear
wheel).
The maximum theoretical sustainable weight on the brake
pad is full body weight -- with the skater balanced on only a single
point of contact with the ground. But this would require a very smooth
consistent ground surface, not always found where quick strong braking
is needed.
What is more stable is to keep some weight on the rear
wheel of the braking skate. That way if the braking friction suddenly
decreases, the lower-than-expected deceleration tends to move the
skater's body backward relative to the braking skate, which tends to put
more pressure on the brake pad, and increases the braking force again --
so it's somewhat self-regulating. Whereas if the pressure on the brake
pad is already at maximum, it can't go any higher to compensate for a
sudden smoothness or slipperiness of the ground surface.
On the other hand, if rear non-braking skate
carries some body weight while the wheel of the braking skate does not,
then these two points of suppport are not as stable, because if the
braking friction suddenly increases, the higher-than-expected
deceleration twnes to move the skater's body forward relative to the
braking skate, which tends to put more pressure on the brake pad, which
intensifies the unexpected braking friction even more, makes the problem
worse - (at least until the rear wheel of the braking skate comes into
contact with the ground again).
My take:
This question of different approaches to weight
distribution for stability and enhanced braking power is mostly
theoretical -- because with most skate wheelframe + boot configuration
designs, takes enormous torque to transfer weight from the rear wheel of
the braking skate to the braking pad. First from the geometry of the
wheelframe + boot, second because successful braking action tends to
push the body's center-of-mass forward.
But transferring weight off from the rear non-braking
skate to the braking skate and its brake pad is pretty straightforward,
because: first, wheelframe-brake-boot configuration has little to do
with it (it's mostly about body joint configuration); and second,
successful braking action helps it happen.
Therefore I suspect that most people overestimate how
much they're achieveing in weight transfer from braking skate rear wheel
to brake pad.
Therefore I suspect a better strategy for most skaters
is to devote more conscious attention to increasing weight transfer from
brake-skate wheel to brake pad (by dropping the knee + hip lower) and
less priority on conscious attention to taking weight off the rear skate
wheels.
The critical requirements for the body position
required to perform this Method effectively are:
-
only the rear wheel and the brake pad of the front skate
are in contact with the ground. (all the other wheels of the front
skate are up in the air -- the rear skate is rolling on the ground
to help balance)
-
the back of the lower leg is pressing against the
inside of the back of the cuff of the boot of the skate.
These requirements imply some other key characteristics
of body position:
-
the whole braking leg must be leaned backward, not
erect, so
-
the hip must be substantially behind the ankle of
the braking leg -- sitting down and back.
-
the braking leg is held straight from ankle to
hip, that minimizes the need to move the hip down and back. The more
the knee is bent, the further the skater must sit down and back,
which is more strenuous on the leg muscles, without increasing
braking force - (dropping the hip back by bending the knee actually
tends to decrease breaking force.)
Moving the weight of the buttocks back and
down is not what increases braking power -- Pressing the back of the
lower leg backward the high cuff of the boot is what increases braking
power. There's no point in dropping the weight of buttocks back unless
you use it to help press the the lower leg backward against the
high cuff.
Here's an example of a skater in position for this
Method:
?? [ insert photo ]
Also look for this position in the videos
??
though note that the skaters are only using this Method
in the final phase of their stopping, so that's when you'll see the
position.
Practice static body position
It's usually not a bad idea to try out this position
while not skating -- perhaps indoors.
In a safe environment in case you fall: no edges or
corners nearby, no protruding objects or surfaces, no objects on the
floor or ground.
At first with a wall or counter-top for support on one
or both sides, and another person to help support you as you try to get
into the position.
Wearing as much padding as you need to be safe.
If in doubt about how to set up the environment or your
equipment or padding or get into this position without any chance of
hurting yourself, then do it only with the help of a good instructor.
?? [ more to be added ]
Once you're in that braking position, you can check to
see if your skating equipment is suitable for using this Method of
braking. Here's the test:
Try to press the back of your lower leg firmly against
the cuff of the boot of your skate, and answer these questions:
if Yes, then OK so far.
if No, is it because the cuff of the boot is so
low that you can't press much against it? (then there's not much hope
for using this Method with this skate + brake configuration --
see this page for other ideas).
or is it because you would have to sit your hip
back and down so far that it takes too much strength or flexibility to
reliably use that position while actually skating? (then there's not
much hope for using this Method with this skate + brake configuration --
see below for other ideas.)
if Yes, then OK so far.
if No, then there's not much hope for using
this Method with this skate + brake configuration --
see below for other ideas.
if Yes, then OK so far.
if No, then probably the cuff of your boot does
not have a good shape for your leg for this Method, or does not have
enough padding on its inside. So there's not much hope for using this
Method with this skate + brake configuration --
see this page for other ideas.
if Yes to this and the previous questions, then
your skate + brake equipment is probably suitable for using this
Method for more effective and quicker braking. There might be some
more tricky problem with it, but that's something your instructor
and you will have to discover and figure out how to handle.
if No, then see the following section for ideas . .
.
If you answered No to one or more of the questions just
above, that's not good for using this Method.
One more thing to try before giving up on this Method
is to check if the brake pad is worn down substantially. If so, you
could try replacing it with a new unused brake pad (which is a simple
modification of the skate + brake configuration), and do the "Equipment
check" again and answer the questions.
Or perhaps your instructor can suggest some other
creative way to use this Method to make effective stops.
Otherwise, the best we know to suggest is to consider
the analysis and ideas on our page for
skates not specifically designed for heel-brake stopping.
Body position for Enhanced level
The strategy for the techique for enhanced level of
braking is to transfer substantial weight from the non-braking skate
(rear skate) to the brake pad (but without putting more weight on
braking skate's rear wheel). The way to make this kind of transfer of
weight is to move more body parts forward and/or upward.
The thing to worry about is that you might get
your weight so far forward that a small variation in braking force might
make you fall down forward. But you might (or might not) find out from
playing with it that this isn't a problem, because your hips sitting
back have already moved so much weight so far back behind the braking
skate.
The second part of the Enhance strategy is to not
allow some of this weight coming off the rear skate to get added to the
braking skate's rear wheel. Since there's more weight trying to come to it
(from moving shoulders and arms forward), it takes more force from the lower
leg into the inside back of the boot cuff to instead "steer" the weight to
the brake pad. Therefore:
Advance exercise
Advanced exercise for skaters with excellent balance who
have mastered the other Basic and Enhanced techniques:
This is to develop balance and feel, expand your range of
options. It not likely that lifting the rear non-braking skate up increases
braking force in most real-world situations -- because weight taken off the rear
skate does not necessarily all go onto the brake pad -- some of it goes
onto the braking skate's rear wheel (which does not help stopping any more than
when the weight was on the rear non-braking skate's wheels.)
And the mental focus to lift the rear foot and balance may
distract too much from the more important focus on transmitting force to the
lower leg and skate cuff from the low knee + hip position.
So there's no simple rule like "lifting rear foot works better"
-- you have to play with different combinations and find out for yourself.
The hard part is getting into the body position and
apply braking force while actually rolling at some significant speed,
without any outside support to lean against.
The next hard part beyond that is to do it reliably in
"real world" situations like on hills and rough pavement -- and "on
demand" when the unexpected happens, not just when you have time to
prepare for stopping.
But that's not something this website is going
to try to do for you -- because different people learn new skills and
balance in different ways -- so what worked for me might not work for
you.
Find a good instructor.
?? For some other ideas about how to learn
heel-braking, consider some of [ these resources ] -- especially the [
videos ]. But note that some of them have some
confusions described below -- so take their many good helpful ideas,
but carefully test the points which might be based
on such confusions. Another reason to learn with an instructor who
can help you sort out what really works for you and your equipment and
your own learning style.
Confusions in some explanations
??
Some websites contain some confusing ideas about
how to perform this method, and seem to be confusing it with other
stopping methods for special kinds of skates or special kinds of
heel-brakes. It is straightforward to identify and avoid these
confusions, then focus instead on learning what really works.
The typical confusion is to suggest
that [[smr: putting body-weight directly over the heel brake is
right and helps stopping for skaters]] it helps stopping for the skater put their body-weight directly
over the heel-brake. But actually [[smr: putting weight
directly over the heel-brake often hinders Method C]] that move often hinders
Method C, for most skate - wheelframe - brake configurations as
supplied by the manufacturer without modification.
Another confusion is to suggest to avoid
straightening the leg for Method C. But extending the knee joint so the
leg is straight from the hip joint to the ankle joint actually makes
Method C easier, since then you don't have to drop the hip down and back
so far.
How could websites have confusions? One
underlying problem for
?? [[smr: websites is a confusion about what method
to use, Method B or Method C, or mixing details of each method together.
]]
these websites might be that they're confusing
how to do Method B with how to do Method C.
?? [[smr:Also, explaining
bodily motions, mechanics and perceptions in words is generally
difficult. Without knowing the special needs of the reader, a
writer must, in advance, provide guidance in a book, website or blog.]]
Anyway it's difficult to
explain something about our bodily motions and perceptions in words the
must be carefully written in advance, without knowing the special needs
of each individual skater, like in a book or website. A big advantage of
a live instructor is that it's usually much easier to see and explain
and show when you're right there together actually doing it.
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??
??
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see also
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