::Snelkracht artikelen
Loren Seagrave sprint seminar
attr: David Hegland -- 2004.04.13
Note from Elliott: This is an excerpt from a posting by David Hegland to the Yahoo Supertraining list.
Was: Is Running that complicated?
Upon request, here is the article in its entirety.
It's quite lengthy. Note that this pertains
specifically to sprinters, as this is Seagrave's
concern. Coach John Davies has mentioned the huge
differences in speed for track and football, for
example. (I'd be very interested in hearing more
about this, coach, if you would.)
**Neuro-Biomechanics of Maximum Velocity
by Loren Seagrave
[Summary by Richie Mercado]
Loren Seagrave has coached several world class
sprinters and hurdlers over the past decade and a
half. Recently he took on the task of training Donovan
Bailey. His company, Speed Dynamics, has sold volumes
of videos and equipment designed to enhance speed,
sprinting, and hurdling through a system he calls
"speed dynamics." He made this presentation to a
group of 80 coaches at the NACACTFCA Congress in
Costa Rica in October 1998, and he focused his remarks
on both the importance of coaching skills and
attitude, and the specific neuro-biomechanical
principles that coaches must take into account when
training their athletes to develop speed.
Loren Seagrave began by describing his recent
experiences as the national sprints/hurdles coach in
Thailand. In his time there he gave six coaching
seminars. The question asked most by coaches was: What
about sports psychology? He would respond,
"Psychology for the athletes or the coaches??" The
beliefs a coach has are often imparted to the athlete,
and while this should be a good thing, too often it is
just the opposite! In Thailand, the coaches have
always said that Thai runners are too short to run
fast, the athletes are lazy and the facilities are
poor. That is exactly what Thai athletes learn! No
wonder they continue to have low goals and little
success. The coaching philosophy must be positive!
Then you can get athletes to have and attain specific
skill goals and enhance their performance.
He posed the question: how many people can wiggle your
ears? Who taught them? No one - they are self-taught!
A person probably did not set out with the goal of
ear-wiggling, but accidentally discovered this talent,
as do many people who learn particular skills.
Seagrave's belief is that most of the fastest people
in world have accidentally discovered how to be fast,
and very few have been taught to be fast! Many coaches
believe that an athlete cannot improve speed (Football
coaches especially), but he believes that everyone can
be taught how to run faster! In this respect, Track &
Field coaches can be so valuable to other sports with
their special expertise.
Seagrave then called on audience participation: in a
seated position he had the participants place their
feet flat on the ground, place their hands on their
knees, and tap their toes on the floor together in
rhythm as fast as they could for 10 seconds. (The
audience then performed this task). He then described
what the coaches were feeling: at "go" they were
busting it, but before 5 seconds, they lost some
coordination or slowed down to keep both feet tapping
together; at 7-8 seconds the speed really slowed down,
and before the 10 second signal, there was some shin tightness or pain!
The point? It does not matter how strong one is, no strength would help to do
that skill
faster or better. So strength is not the key.
Speed is a skill: just like any other skill, it can be
improved. Any coach can make you tired - but that is
not the purpose of training for speed; the purpose is
to become faster! A coach must apply a systematic
approach to improvement. There is also a profound
difference between coaching and training.
Coaching vs. Training
Perhaps if the word "Teaching" is substituted for
"Coaching" the important differences will become
more clear. Training is developing the physiological
qualities through work. Coaching is teaching! But
coaches cannot just teach during certain times of the
training. Coaches must be present during all of the
preparation, drills, and training to ensure that the
athlete is performing them well at a very high level.
The coach should empower the athlete with the
knowledge and the tools to become more self-sufficient
as they develop.
Seagrave said that he has four new athletes with an
average age of 33 years. He tells them that if they do
not understand why they are doing something in
training, they are a fool not to ask! An athlete
should understand how every component of training is
going to help them achieve their ultimate goal! The
more they understand, the better the compliance with
the training program, and the likelihood of excellent
training is increased! Athletes also make excellent
peer coaches in a group!
It is a total reclamation project when a coach starts
with a new athlete: the coach must help the athlete
unlearn old bad habits and relearn proper patterns
from scratch! He noted that his recent experiences as
the speed development coach for the Atlanta Falcons of
the National Football League have demonstrated this
clearly. Football players, like any athletes, go
through four stages when learning a new skill:
1st Stage: Unconscious Incompetence
The athlete is not thinking because they have never
been told to think about anything, and is not very
good at new skills. He said that he tells the football
players that it is better to look foolish in front of
your teammates in practice and get better at the
skills than to get embarrassed on Sunday in front of
80,000 people and a TV audience! In this stage, the
coach must convince the athlete to lose the
inhibitions to looking foolish.
2nd Stage: Conscious Incompetence
The athlete knows what to do but has not mastered the
skill; they consciously try to execute it, but are not
very good at it yet.
3rd Stage: Conscious Competence
Athletes very quickly progress to conscious
competence, where they are skilled but only with
conscious effort; they cannot do it automatically and mindlessly. In this
stage, unconscious action returns one to previous bad
habits. The example Seagrave gave was someone trained
in the martial arts would, when confronted by an
attacker, most likely revert to ugly, unskilled
fighting habits when in this 3rd stage.
4th Stage: Unconscious Competence
The skill is automatic and performed perfectly with no
conscious effort. Attainment of this level takes not
only practice, but mental imagery and rehearsal. It
can take up to 500 hours of practice to achieve
unconscious competence with a skill!
With amputees there is something called the Phantom
Limb Phenomenon. Someone who has lost a limb feels as
if it is still there; all sensory receptors are still
connected to the brain despite loss of the limb; it
can take up to 500 hours before the brain figures out
that these are false receptions! What this means for
coaches is not necessarily 500 hours of skill work on
the track, but mental rehearsal and imagery practice
of a skill counts to help reduce the time to attain
unconscious competence!
With respect to skill development and ultimate
performance enhancement, Seagrave stressed that
coaches must develop a mission statement for their
athletes. This statement should pinpoint what the
athlete must try to do every day to reach intermediate
and long range goals. An example of a mission
statement for a Sprinter / Hurdler might be:
Sp/HH Mission Statement:
- Reduce the time needed to put the required force
into the ground by 0.005 seconds
- Reduce the time needed to recover the leg through
the required range of motion by 0.005 seconds
These may sound like modest goals, but saving 0.005
seconds on the ground and 0.005 seconds in the air
saves 0.01 seconds per stride in a 50 stride 100 meter
race! That means the athlete has saved 0.5 seconds!
What athlete would not want to drop 0.5 seconds off
their 100m, 100 Hurdle or 110 HH time? If one computes
this out for other distances, here are the results:
0.2 seconds in the 40 yard dash (distance most used in Football)
0.5 seconds in the 100 meters
2.5 seconds in the 400 meters
Marathon: 3-5 minutes!
The big question is: How can this be accomplished?
There are four different ways:
- Apply greater force;
- Apply force in less time;
- Apply force in the proper direction;
- Apply force through the proper range of motion.
Objectives -
- Apply greater force. Should this be done simply by
hypertrophy or non-traditional recruitment of greater
number of motor units? Remember the toe-tapping
principle? Motor unit recruitment and inhibiting the
inhibitors is the answer - coaches and athletes must
get rid of the speed governors! This is just like the
little old lady stories about grandmothers who lift
the car off of the person who is trapped: all of the
inhibitory overrides through the Central Nervous
System (CNS) have been removed and all muscle fibers
are recruited! Massive injury may and probably will
occur to the little old lady, though! Coaches can
teach athletes how to reach deeper into their power
stores and allow them to feel competent and that they
have a high level of ability!
How competent do young hurdlers feel staring down that
long line of 10 hurdles? They will be guarded and
reserved. Training must allow them to develop a
competence above their performance: teach for success
- Athletes must learn how to apply the force in less
time! An example was demonstrated by Seagrave: place
the hand palm down on the table and raise and tap the
index finger on the table as hard and as quickly as
possible one time. Then pull the index finger back
with the other hand and let go! The stored elastic
energy - stored in muscle and tendon and fascia
surrounding muscle - provides a greater force in less
time. This is the stretch-reflex principle of muscular
contraction. Muscle contraction alone is severely
limited due to restraints of speed of contraction, but
this elastic stretch-reflex helps make up for lack of
fast twitch fibers, too.
- Athletes must apply force in the proper direction.
Forces must be forward and backward, not side to side,
but without the braking forces that are often applied
by athletes reaching with the touchdown too far
forward of the center of gravity, resulting in loss of
velocity and force.
- Athletes must apply the force through the full or
optimal range of motion. As speed increases, force on
the ground is applied over a smaller range of motion
than during acceleration.
Mann pointed out that the angle on knee and hip
extension at maximum velocity is smaller in elite
class sprinters. The goal is to apply the necessary
force in as small a time as possible and a thus the
range over which it is applied is reduced at maximum velocity.
If Maximum Velocity = Vmax; Stride Length = SL; and
Stride Frequency = Sf, then: Vmax = SL x Sf
Perhaps it would read better as: SL = Vmax / Sf
In other words, the faster one travels, the further
one flies through the air! The traditional focus was
on stride length and the concept that more strength =
a longer stride. But it is coordination that is the
limiting factor, and more strength does not
necessarily do it, as demonstrated by the toe-tapping.
SL is concrete as a value, so coaches have liked to
use it, but Sf is very nebulous, confusing, and more
abstract to many coaches. Mann and other researchers
and coaches feel that stride frequency is the more
important component.
Stride Length
Take a young Costa Rican sprinter and say, "Run with
long strides for coaches." She would probably
exaggerate her strides to please the command of the
coach. She would increase her actual SL from the toe
of the right foot at takeoff(t.o.) to the toe of the
left foot at touchdown(t.d.). This is the simplistic
concept many athletes have of stride length. But SL is
better understood in relation to the athlete's Center
of Gravity (COG), and the distance the COG travels
from t.o. to t.d. is used to figure the actual SL.
The longer the distance the athlete's body travels
while on the ground, the more time is spent, and the
slower the Vmax. The relationship between ground and
air distance for COG should be long air distances
relative to ground distances! Change how the athletes
look at SL, maybe by utilizing the concept of
effective SL: the distance the hip travels through the
air in a stride. The goal is big air distance and
small ground distance. Therefore, during acceleration
runs and buildups, force should be applied into the
ground with the goal of projecting the hips forward as
far as possible.
Stride Frequency
Ground Time (GT) + Air Time (AT) = Stride Time (ST),
or the time it takes to execute one stride. Here is
the data for elites: it is not uncommon for GT to be
0.09 seconds and AT to be 0.11 seconds = ST of 0.20
seconds.
Therefore: 1 second / 0.2 = 5.0 strides per second.
4.8 - 5.2 strides per second is the range for elite
sprinters. Young athletes' values are: GT = 0.12 seconds
In other words, the force applied into the ground at
Vmax is virtually identical in relationship for a slow
High School boy and an elite male sprinter, so what is
the difference? Time! Elites put the same force into
the ground in less time and the hips project forward a
farther distance.
AT = 0.13 This is lower due to lack of skill and motor
coordination.
Sf = 4.0 strides per second. It is not strength which
distinguishes elite sprinters from average ones, but
efficiently reduced ground times due to enhanced skill
and motor coordination.
Videos of High Level Sprinting
Loren Seagrave then showed some video of sprinters to
focus on aspects of sprint mechanics. The first
example was of Andre Cason one week prior to 1992
Zurich meet. He said that most people would see a
little short guy running fast! Coaches and observers
do not have their minds ready to analyze and break
down the key components at regular speed, so he froze
certain frames and slowed down other parts.
Important in understanding sprinting are the Cyclical Movement
Phases: these occur over and over and over again
throughout the course of a race! This is much
different from an acyclical movement; the quality of
each one of the phases of the movement depends on the
quality of the phase that precedes it. The ground
phase is the most important, yet the quality of the
ground phase is determined by all phases that come
before it!
- Residual Phase - from the moment the toe leaves the
track (T.O.) until the thigh begins moving forward in
recovery.
- Recovery Phase - from the moment the thigh begins
moving forward until the thigh stops (blocking)
- Transition Phase - from the moment the thigh blocks
until the thigh begins to accelerate in a negative direction.
- Ground Preparation Phase - from the acceleration of
the thigh in a negative direction until touch down (T.D.).
- Frontside Ground Phase - From the instant of T.D.
until the COM is over the base of support (contact point of foot).
- Backside Phase - from the midstance of support over
the foot until the Takeoff (T.O.) into the next Residual Phase.
Vital to the development of maximum velocity sprinting
skills is a proper understanding by coach and athlete
of the following: there is a big difference between
quality and intensity. Intensity is the % of maximum,
say 90% of Vmax (90% of 10meters/second = 9meters/second).
Quality is a measure of the % of perfection - even if not done at 100% of
intensity!
There is no excuse to do any work at less than 100% of
quality, no matter what speed or intensity.
The practical applications for coaches and athletes
developing the appropriate skills in each of these
phases include neuro-biomechanical cues to allow for
proper positioning and muscular response in the cyclical phase.
The prime example comes in the transition into the Residual Phase, where the
brain
must send the message to dorsiflex the foot before
T.O. into the Residual Phase. German studies have
shown EMG messages occurring while the foot is still
in contact prior to T.O. At T.O. there is stored
elastic energy if the foot is dorsiflexed, thus
reducing the amount of time required to recover the
leg (i.e. get the thigh and leg moving forwards sooner
after T.O. to save time in the Recovery Phase.
The cue for therapists when reteaching someone to walk
is not to lift the knee, but lift the top of the foot!
This evokes the ‘'triple response'‘; by curling the
toe up (lifting the top of the foot) the knee and hip
also respond! Those with too pronounced backside
mechanics and slow recovery do not send this message
of dorsiflexion soon enough. Since recovery requires
velocities of over 400 degs/sec, the smaller
muscles must do it, not the larger ones.
The Gastrocnemius (begins above the knee and goes down to
achilles) becomes an extremely fast knee flexor!
Joint position dictates muscle recruitment (this is
the Speed Dynamics principle), with dorsiflexion of
the foot and other joint movements. If one raises
their arm and holds their biceps, then rotates the
palm, it is obvious that pronation turns on, and
supination turns off the biceps (this is why it is
easier to do closed-grip rather than open-grip
pullups).
In cyclical motions, part of time muscles
must contract, and part of the time they must relax.
Hip extension from ground contact through the Drive
Phase is vital, and requires hamstring contraction. If
the hamstring contracts during the Recovery Phase then
it does not have time to relax, and the result is
either premature fatigue or worse, injury! By reducing
the moment of inertia through dorsiflexion of the toe,
then Recovery is quicker and allows the hamstring to
relax and recover for the next contraction during the Drive Phase.
When young people learn to bat in baseball and they
swing the bat too slowly to hit the ball, the
appropriate adjustment is to choke up on the bat and
thus be able to swing faster. If the length of the leg
is shorter, then it too can swing faster! The same
principle also works in sprinting. Just before the
Transition Phase - when the thigh blocks - coaches
will often observe athletes floating in the air in a
blocked motion. The legs work in concert and in
opposition, so a blocked leg cannot go down until the
opposite leg begins to move forward - in other words,
they need to work on the Recovery Phase to enhance the
Transition Phase! Coaches can drill athletes to use a
maximum acceleration of the hip flexors and a maximum
deceleration of hip extensors by means of a fast leg
drill.
Coaches and athletes must understand and
identify key regulatory factors (Maraj) that are going
to limit performance and develop learning and skill
routines that will enhance sprinting skills. In this
fast leg drill, the cues are for the athlete to get
the ankle cocked and step over the opposite knee to
thigh block, then accelerate the thigh backwards into
extension. It must be a short lever: shorter = faster!
Athletes can control when they send the neurological
message to the quadriceps to extend the knee. Insure
that the quad muscles stay relaxed, and remember that
the lower leg stays in the same position and neither
adds to length or mass of the leg lever. Sprinters
should first accelerate the long lever, then
accelerate this long lever against the ground by
contracting the quadriceps. According to Mann, top
sprinters maintain a lower angle longer, thus
maintaining greater speed at the knee and foot going
backwards. There are also smaller distances from the
COG to TD in elite sprinters; beginners have bigger
distances, thus creating greater breaking forces and
loss of Vmax with each TD.
The cue should be to keep the ankle cocked
(dorsiflexed) thus preparing the Gastrocnemius and
Soleus muscles for contact. This muscular resistance
upon TD will reduce amortization (collapse and loss of
energy) prevent the toe pointing down, which tends to
place TD even farther in front of the COG.
The stretch reflex from dorsiflexion turns the ankle
joint into a mechanism akin to the horse's fetlock
joint: no muscles cross the joint, just a thick
non-elastic ligament. The gastroc-soleus-Achilles
complex in humans stores energy and projects us
forward more quickly, minimizing amortization.
Another cue to look for as a coach is the angle
between the thighs at the moment the foot touches the
ground. The knees should be at least together: an
excellent measure of quality and perfection of leg
recovery mechanics. If there is light, i.e. some angle
between the legs at TD, then a forward TD and braking
is occurring, thus Vmax is reduced. In drills,
sprinters should shift the hip forward - this avoids
stress on the ham from hip back. The shoulders should
remain directly above the hips, and the athlete should
use the lower two abdominals to stabilize the pelvis
(the upper four are used for breathing). This is a
skill, and like any it can be unlearned and overridden
by bad technique!
The sprinting action can be practiced in a Whole
Method by maintaining a stable and upright torso, then
dorsiflexing the foot (thus initiating the triple
reflex of the ankle-knee-hip joints), then drive the
thigh down and grab back into the ground and end up
tall with the hip over the knee. Excellent strength
exercises that will enhance the specific strength of
the sprint cycle are squats, lunges, stepups, and bounding.
In sprinting, arms are like operating a vehicle on a
one way street - they only drive one way - backwards!
The arm action should take place in a loose 90% angle,
with the athlete driving the arm back to store elastic
energy in the shoulder and biceps.
Do not paddle with the hand palm-down, because it will
relax the biceps!
Some important drills to teach sprinting skills include:
- Ankling - maintain body position (posture) and
dorsiflexion(keep the bottom of the foot pointing down
to the track and do not push from the ankle) while
stepping over opposite ankle!
- Cue - tie your big toe up to your knee joint! use tape
and FEEL the proper movement! There may be a problem:
the new, more optimal way does not feel right, but it
is vital to feel it anyway.
- Butt Kicks - dorsiflex ankle, use gastrocnemius as the
knee flexor (initiate the triple flexor response),
preserve good body position and proper pelvic tilt,
crash calf into ham and see knee move forward ever so
slightly as knee is flexed. One athletes described it
as trying to comb their hair with their spikes!
A Series - dorsiflex ankle (initiate the triple flexor
response) and block thigh, then accelerate thigh back
down towards the ground.**
Regards,
David Hegland
North Dakota
::contents © Elliott Oti 2002-2004 where applicable
