Ken Roberts
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Heel-Brake | more Stopping
Lots of people on inline skates can't stop quickly,
even though one of their skates has a heel-brake on it.
There's several helpful web pages for learning the
skills of how to
stop with a heel-brake: see Resources
for Learning Stopping. But for now (November 2005) they teach only
one or two out of the three possible methods, and seem to assume that that
limited set of methods will work for all heel-brake designs and all
skate + frame + brake configurations.
But the range of skate + frame + brake configurations
is too wide for that, so sometimes the limited methods don't work.
Sometimes one method will work when the brake pad is worn down, but a
different method is needed when the skater replaces it with a new brake
pad. So skaters feel confused, and they say, "heel-brakes don't really
work", or some can even fall into saying, "inline skates really just
can't stop well".
Or sometimes a web page or instructor mixes up moves
for two different methods of heel-braking -- and sometimes those moves for
one method are in contradiction with the effectiveness of the other
method.
My key points are:
-
Stopping quicker on inline skates usually requires
learning some special skills and balance. Just having a heel-brake
and pressing it down is not enough.
-
There needs to be a preliminary step before
learning any heel-braking techniques: To first check their current
skate + frame + brake configuration to find out which of the three
methods are possible, and which of the possible methods should be
primary.
-
Focus on learning the moves which are key for the
effectiveness of the primary method, and avoid moves which
contradict it.
who is it for?
The ideas on this page are intended for
I think that a good instructor, even if
they can't understand the underlying physics, should try the Big B
Test and see how it comes out for different models of skates. And
try some of the different methods with
different skate + brake configurations, especially with both new
brake pad and very-worn-down brake pad (and if possible with
speedskates with a heel-brake) -- and what happens when you to take
the key steps from one method and try to
use them with a different method.
-
designers and distributors of inline skating
equipment -- so they can target and recommend brake designs and boot
+ frame + brake configurations which are appropriate to different
skaters with different needs.
-
learning inline skaters who want to assess if their
instructor has the capability to help them learn effective stopping
with their skate + frame + brake configuration.
Like if you've got skates designed for
method C, there's no point in trying to learn from an instructor who
doesn't know how to perform method C very well, or doesn't even
believe in method C.
Not intended for
Actually I'm generally in favor of special
mechanical assistance designs for stopping, and the ABT is surely an
important one. But I can't say much about it because I haven't gotten the chance to try it.
Most skaters with some sort of balance
capability using most normal "general recreational" skates which are
sold with a heel-brake already on them in the box can learn
effective heel-brake
stopping from some lessons with a good instructor and some practice.
Watching some
video
examples usually helps, too.
Even if the instructor doesn't know the
theory on this page, when they watch you actually skate, they can
usually figure out what you need to hear in order to get you past
the problems you're having with stopping (with some practice).
Heel-brake stopping is not "rocket science" with most "general recreational"
skates (not specialized for hockey, dance, racing, tricks, etc.) For most people it's a matter of getting comfortable (in
stages) with a special kind of balance. And that's what lessons with
a live human instructor are good for: helping you through those
stages of balance comfort.
Learning to stop effectively is very
critical safety skill -- too important to trust to reading some
words on a web page and hoping you can figure it out. Find a good
experienced instructor who can show you and teach you an effective
stopping method which is appropriate for your equipment.
Who am I?
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).
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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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These are the three biomechanical methods I've found
(so far) to generate downward force on the heel-brake pad on a "normal"
skate, without considering any of the different special "mechanical
assistance" devices that are available (e.g. leash, ABT).
(A) muscle-torque-thru-ankle-joint
Apply a muscular force-pair ("torque") thru the
ankle joint from the shin muscle, by pulling up with the front part of
the foot against front part of the upper of the boot, and pushing down
on the heel -- with the force coming primarily from isometric shin
muscle activity.
(B) gravity-directly-thru-ankle
Position the ankle and foot so that
gravitational force from body-weight is transmitted down thru the ankle
joint, which must be positioned behind the rear wheel.
(C) leg-back-against-boot-cuff
Angle the whole leg backward, which forces the bones of the lower leg to
press the inside rear of the high cuff of the skate boot backward and downward
-- with the force to hold the leg straight coming mainly from the hip-extensor
muscles.
The big trickiness about how heel-brake stopping works
is that with many skates and brakes, using body-weight actually reduces
braking force -- but with others it adds braking force. With many
skates, just changing the brake pad can switch it from one to the other:
body-weight adds versus reduces versus adds braking.
The big contradiction is between the body positions for
B and C. Gravity-directly-thru-ankle method (B) delivers its maximum
force with virtually all of the skater's weight on the front braking
skate. But angling the whole leg back far enough to get substantial
force from Leg-back-against-boot-cuff method (C) is going to require
significant body weight on the rear supporting skate. Some skate+brake
configurations are good for B only, others for C only, some for both,
and most 5-wheel speedskates for neither.
[ see other
contradictions further below ]
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Q0: Goals and Balance capability
best to find an instructor who can help you work thru
these questions.
C-test: Does your skate boot have a high enough boot cuff?
This test is intended to answer:
Does your skate boot have a high enough boot cuff to
support effective stopping by pressing the lower leg back and down
against it?
see more
B-test: Is direct body-weight working against you
or for you?
This test is intended to answer:
Is trying to put your body-weight directly over the
heel-brake working against you or for you in your stopping?
Is this test necessary?
-
If your skate + brake work well with method C, and
you don't have any interest in using method B sometimes, then No
this test is not necessary -- provided that you follow these:
-
Do not try to shift your body weight forward to
more over the braking skate.
-
Apply force to the front braking skate only by pressing
your leg back against the rear of the cuff of the front boot, by using
your leg bone structure and muscles (but not by weight-shift). Or
it's OK focus the
distribution of force within the foot more to the brake pad by using the
muscular force of method A.
-
If you're using the mechanical assistance of a leash (and
never intend to use B as a backup method), or if you have amazing
special-muscle strength to make your method A stopping strong enough without
assistance, then No this test is not necessary -- provided that you follow
this:
-
If you want to try to use method B as a primary or back-up or
supplemental method, then Yes you should do this test.
-
If you want to feel free to shift more weight forward over the
braking skate (perhaps for balance while stopping?), then Yes you should
do this test.
-
If you're using a speedskate boot or frame with a
heel-brake, then it's pretty likely that you should be doing this test.
see more
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Key steps to make each method effective
method A : muscle-torque-thru-ankle-joint
Very few people can get strong braking using only method A,
because the main muscle used for method A is just not very big. But method A is
a straightfoward way to supplement other methods, so it's worth working on it.
The keys for making this method work better are:
Which implies that until that special strength
ever arrives, you need some other method to deliver strong
braking force when needed.
Do not pay attention to claims that pulling up
with toe or front of braking foot is "bad form". That might perhaps be
unnecessary or somehow bad for some other method, but pulling up with
front of the braking foot is an essential component for method A.
If your heel-brake and/or skate + frame + brake
configuration are currently "neutral" or "positive" under the Big B Test,
then this is not a concern.
But most brakes + skates are "negative" under the Big B
Test sometimes, especially when the brake pad is new. So when in doubt,
follow this . . .
For method A, do not listen to intuitively appealing
advice to consciously shift your weight forward more over the braking skate --
that advice is for method B.
Trying to combine method B simultaneously with method A
will result in reducing the braking force if the brake + skate are
currently "negative" under the Big B Test. Or will give no help if the brake +
skate are currently "neutral" under the Big B Test.
Only shift your weight consciously to the front
skate for method A braking if you know that your brake + skate is
currently "positive" under the Big B Test.
> > > see more details on Method A :
equipment - balance - strength - interactions
method B : key steps for
gravity-directly-thru-ankle
balance
Trying to get maximum braking force with
Method B requires very good balance, because the skater is trying to put
lots of weight on the front skate, and the two ground-contact points for
the front skate during braking (its rear wheel and the brake pad) are
very close together.
So lots of skaters put more weight on the rear skate
for easier balance and control, and get supplemental braking force from
other methods, rather than worrying about maximum from method B.
modify equipment
Getting more out of method B -- and often getting any
braking force out of method B -- usually requires modifying the heel-brake
design or the skate + frame + brake configuration.
options include:
Brake pad rubber is not so easy to cut or
grind unless you've got suitable power tools. I don't have such power
tools in our apartment, but I was able to cut down one of Sharon's brake
pads using a hacksaw.
I think cutting the brake pad down could be a
good one-time strategy for while learning method B, to make it
extra-easy to get the feel and balance of getting lots of body-weight
into the stop. But if I thought I'd have to cut down every replacement
heel-brake-pad I bought before using it, I think I'd prefer this:
as of November 2005, the after-market
heel-brake offered by Miller Sports has a bigger pad-to-ground gap than
some other models, and is compatible with many (but not all) speedskate
wheel-frames.
-
Change the mounting of the wheel-frame, to move the wheel-frame
further forward relative to the boot -- so ankle joint is back closer to the
brake pad.
-
Switch to a different wheel-frame which doesn't stick out so
far behind the skate.
-
Manage the overall strategy for braking so that
some other method is used to deliver stronger braking force
when needed -- while waiting for a new or replacement brake pad to
wear down to a big enough gap for method B to deliver substantial
force.
Perhaps some options for the "other" method
might be: (1) a second heel-brake on the other skate, with a brake-pad
already worn down to enable use the combination of methods B and A to
deliver strong braking force -- while for situations that do not require
strong force, method A is used to wear down the first brake pad; (2) the
mechanical assistance of a leash. My experience is that (1) is
complicated to manage, and but it's made less hard by adding (2) in
combination.
warnings
Even after modification, there are very very few skates with
brakes that are not sometimes "neutral" or "negative" under Big B Test.
Which implies that
> > > Sometimes method B cannot
work. Not at all. < < <
So the skater must have some other sufficiently-effective
stopping method ready to use for that situation. Most skaters who like method B
use as their "backup" stopping method A, sometimes with the special mechanical
assistance of a leash.
> > > method B alone is usually
not sufficient for a strong quick stop. < < <
So when a quick strong stop is needed, the skater must have
some other sufficiently-effective stopping method ready to help. Most skaters
who like method B use as their "supplemental" stopping method A, sometimes with
the special mechanical assistance of a leash.
move
?? [ more to be added ]
The key skills for this method are:
-
Learn to commit more weight to the front braking skate.
(see tips below)
-
Get good at using some other effective braking method --
different from B but compatible with B -- which can be used as a "supplement" or
"alternate back-up" as needed.
Method A is the obvious choice, and it's
usually straightforward to overlap methods A and B and shift the
proportion between them as needed. But method A might not be sufficient
as a supplement for some skate + brake configurations for some stopping
requirements.
-
Detect when the current skate + brake + body-weight
configuration is "neutral" or "negative" -- and get good at easily and
quickly switching to a different braking method other than B.
-
Do not try to commit more body-weight to the front skate when
the current skate + brake + body-weight configuration is "negative".
Ideas for learning to commit more to the front skate:
practice standing still (indoors) with nearby supports -- less
and less weight on the rear skate. Try to get to lifting the rear skate off the
ground and feeling what it is to balance on only two points:
"final exam" of expert-level method B is to make a stop (in
favorable terrain) with full body weight all on the front braking skate, with
the other skate a little ways up in the air.
?? [ more to be added ]
> > > see more details on Method B :
equipment - balance - strength - interactions
method C : key steps for
leg-back-against-boot-cuff
Basic level
Purpose: To press the brake pad strongly against the
ground, and transfer weight from the braking skate's wheels to the brake
pad, while maintaining stable balance.
Strategy: Use pressure thru the back of the lower leg,
supported by the big leg muscles. Learn stable balance thru progressive
exercises.
(1) Find out if the design of your
boot-wheelframe-brake configuration is a reasonable candidate for trying
this method.
Typically if the skate did not come in the box
with the heel-brake already attached when you first bought it, then it's
not a candidate for this method.
(2a) Find a safe learning and practice environment.
(2b) Look at some videos of how this method is supposed
to look when it works.
(2c) Find an experienced instructor who understands and
can demonstrate this method.
(3) Balance: Learn to roll gliding forward with
the braking foot fully out in front of the non-braking foot. (a) first
with all wheels of the braking skate on the ground, then (b) with only
the rear wheel of braking skate (and all wheels of the non-braking
skate) on the ground, then (c) with the front skate tilted back far
enough so the brake pad touches -- rolling with both the rear wheel and
the brake pad touching the ground (and all wheels of the non-braking
skate on the ground).
Often called the "scissor" position -- several
websites and books give tips and exercises for how to learn it -- see
these
resources.
(4) Knee backward: With the braking skate fully out in
front, tilted back with its rear wheel and brake pad touching the
ground, move the braking leg's knee backward and downward. Press the
back of the lower leg against the inside of the back of the high cuff of
the skate boot. Since the back of the boot is stiff, this presses the
brake pad harder against the ground, which normally causes stronger
quicker stopping.
Adjust balance to compensate for the force of
the braking foot slowing down, so don't fall over forward.
More pressure thru the lower leg backward
against the inside of cuff, stronger stopping (if you don't change
anything else in your body position).
(5) Hip-Knee relationship: Braking leg's knee joint
extended to as straight as possible.
The hip joint is connected to the knee by the
upper leg bone, so if the knee goes backward, the braking leg's hip must
also go backward and downward. But "sitting back" with the hip is just a
necessary side-effect of the lower leg with knee move -- the hip move
doesn't actually help braking. So the hip and upper leg should move
backward no further than required by the lower leg with knee move. The
way to do this is to keep the braking let as straight as possible thru
its knee joint.
(6) Verify that the design of your
boot-wheelframe-brake configuration really works for this method.
Enhanced level
Purpose: To increase maximum braking force when
especially needed: Transfer more weight off from the non-braking
skate onto the brake pad, without much of that transfer going to the
rear wheel of the front skate instead of the brake pad. The lower
percentage of the skater's weight is supported by any wheels on the
front or rear skate, then the more weight is pressing down on the brake
pad, and (normally) the stronger and quicker the stopping.
Strategy: Bring more body parts (other than the braking
leg's knee) forward and upward -- but not so far forward that
significantly more weight goes on the braking skate's wheel instead of
the brake pad (also make sure not to actually fall over forward if there's sudden unexpected additional
braking friction). Learn balance more precise and more stable.
(1) Bring the shoulders forward.
Try comparing stopping with shoulders high and
erect directly over the hips versus shoulders leaned forward: Can you
feel the difference in the quickness of stopping?
(2) Bring the arms and hands forward and up.
Try comparing stopping with arms hanging down
by hips and shoulders high and erect directly over the hips, versus
hands and arms and shoulders way forward: Can you feel the difference?
Maybe not: there's such a thing as too much
weight forward. Play around with finding out where bringing hands and
arms and shoulders forward (and up) doesn't seem to make the stopping
quicker and stronger -- or even makes the stopping weaker. No point in
doing extra work which is not effective.
(3) Keep the braking leg's hip forward and up as much
as possible by keeping the knee joint extended close to straight.
Try comparing stopping with knee bent less
versus knee bent more versus knee straight. What's the difference?
(4) Keep focused on driving the knee backward and
downward to press the lower leg strongly against the inside back of the
boot cuff. This means that the hip must keep driving backward and
downward.
Mental image: Try to "dig" the brake pad into
the ground so strongly that the braking skate's rear wheel comes all the
way up off the ground. (I'm not sure if physically raising the wheel off
the ground delivers more braking force -- or if it's even possible with
some skate designs. But the mental image of trying to do that
might help increase braking force -- another thing to play with.
(5) Contradiction of moves: Get comfortable with
getting the shoulders forward (and partly up),
at the same time you're driving the knee and hip down and backward.
The apparant contradiction might not be just
apparent -- there might be a real trade-off here: So play with what
variations in position produce more or less stopping power. Apart from
analysis of trade-offs in the objective physics, my personal experience
is that it's more important to keep my conscious mental focus on
pressing the lower leg to "dig" the brake pad.
Why not "keep it simple" by just focusing on
one thing: getting weight forward over the brake pad? Because just
bringing weight forward tends to put more of it on the braking skate's
rear wheel instead of on the brake pad. It's usually easy to transfer
weight forward from the non-braking skate to the braking skate. It's
normally hard to transfer a substantial percentage of weight off from
the braking skate's rear wheel onto the brake pad.
(6) Balance: Feel and play with the balance -- how far
forward you can move more body parts -- how little weight you can leave
pressing on the rear non-braking skate -- what's really effective for
stronger stopping and what isn't.
(7) Quickness: Practice quicker initiation of the
braking position and moves from the midst of normal skating strides.
When the unexpected happens and you really
need a quick stop, it's not enough to know how to apply maximum
friction thru the brake pad. Because you don't get that maximum friction
power helping you until you get into position and actually start doing
it. Every moment of delay before starting the actual braking takes you
closer to the thing you don't want to hit.
Practice quickness. Practice from your normal
skating striding speed. Then practice to get quick confident initiation
of strong braking from your normal striding speed on a gentle downhill
(in an environment with a safe flat run-out below the downhill). Also
practice to get quick confident initiation from coasting down hills
(with a safe flat run-out below) of steepness that you want to be able
to handle in your skating tours.
expert "precision" level
Purpose: Precise positioning of body for maximum focus
of body weight on the brake pad, minimun on the any of the wheels of the
real or front skate.
This is only important for maximum
stopping power -- something most skaters should rarely need. It's much
more important to practice to be able execute an imperfect stopping
position quickly and confidently and reliable, than to spend lots of
time refining body position.
Strategy: Learn to stop with all the rear skate's
wheels lifted off the ground.
(1) Expert's balance drill: Play with lifting the
rear skate all the way off the ground.
Perhaps can work toward this by
steps: Of course first have to be complete solid and confident rolling
on one skate without any braking. For braking, could first try with
feeling reduced weight on rear skate. Or play with only the rear
skate's toe wheel on the ground while heel-braking. At last try lifting
the skate just a little ways off the ground, so you can immediately
confidently set it down again if you need to.
(2) Expert's body position tuning: Hands and arms and
shoulders no further forward (or up) than necessary to just barely get
all the rear skate's wheels up off the ground.
Find the upper body configuration which
accomplished that and feels most controllable and comfortable.
(3) In real world stopping, it's not critical whether
the rear skate is all the way off the ground or down rolling with small
percentage of weight on it.
If having the rear skate on the ground helps
you feel confident to "dig" the heel-brake more strongly into the
ground, that's the more important thing.
If you are devoting any conscious energy to
keeping your foot off the ground, then it's probably not worth it. Put
your energy into digging the brake pad into the ground stronger and
"deeper", and watching for the unexpected.
If you do have the the rear foot in the air,
probably good to keep it close to the ground -- ready to
immediately support you and initiate a recovery move in case something
unexpected happens.
> > > see more details on Method C :
equipment - balance - strength - interactions
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-
The big contradiction is between the body positions
for B and C: weight directly over the front braking foot versus leg
angled back which puts upper body over rear supporting foot. (see
"Trickiness and Confusion" above under Three Methods)
-
some boot designs which are stiff to support C can
make it more difficult to make the "ankle dorsi-flexion" move to tilt
the foot back into position required to get the ankle joint behind the
rear wheel to exploit gravity (B), or difficult to get into the best
configuration for muscle-torque-thru-ankle-joint (A). Of course a (more
expensive) boot could be designed with both forward-freedom for A+B and
backward-stiffness for C.
-
smaller contradiction sometimes between C and A: at least it
feels to me like I can't exert as much shin-muscle force when my leg is
angled way back.
-
small contradiction between equipment for A+C versus B:
Small vertical gap between brake pad and ground makes balance for A easier
for beginners, since do not have to advance braking skate as far forward,
and makes C easier because the leg can be angled back less. But larger
brake-pad-to-ground gap is often a key requirement for making it possible to
get any help from B.
On other hand, perhaps this could lead sometimes to a nice
complementarity between methods B and C: Focus on C when the brake-pad is new, then
more toward method B as the pad wears down and the gap is bigger. The
problem with using different methods for different pad-wear situations is
forgetting which method is the one to use currently. Since the moves for B and
the moves for C are somewhat in contradiction, this is not a trivial problem, if
your attention is focused on a sudden obstacle that is requiring an unexpected
quick stop.
One approach I've tried is to use two brake pads, and
always switch the more worn-down brake pad to the left skate and put the new
replacement pad on the right skate, so that my left foot learns to focus on
method B (combined with method A), while my right foot learns to focus on
methods C (and also A, whose moves do not much contradict C).
see also
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