A process for error correction for strength and conditioning coaches

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A Process for Error
Correction for Strength
and Conditioning
Coaches
Emily Cushion, MSc,1 Louis Howe, MSc,2 Paul Read, CSCS,3 and Adam Spence4
1School of Sport, Health, and Applied Science, St Mary’s University, Twickenham, United Kingdom; 2Department of
Medical and Sport Sciences, University of Cumbria, Cumbria, United Kingdom; 3Athlete Health and Performance
Research Centre, Aspetar, Doha, Qatar; and 4Strength and Conditioning Coach, London, United Kingdom
A B S T R A C T
THERE ARE SEVERAL SKILL
ACQUISITION STRATEGIES AVAIL-
ABLE TO COACHES WHEN COR-
RECTING A MOVEMENT ERROR.
HOWEVER, IT IS NOT ALWAYS
CLEAR WHICH STRATEGIES
SHOULD BE USED FOR A SITUA-
TION AND IN WHAT ORDER. THIS
ARTICLE AIMS TO PROVIDE
COACHES WITH A LOGICAL
EVIDENCE-BASED PROCESS TO
ASSIST THEIR COACHING PRAC-
TICE. IN ADDITION TO A PRO-
POSED MODEL OF ERROR
CORRECTION, EXAMPLES ARE
PROVIDED FOR SEVERAL COM-
MONLY OCCURRING SITUATIONS
IN STRENGTH AND CONDITIONING
PRACTICE.
INTRODUCTION
E
ffective strength and condition-
ing (S&C) practice requires the
integrated application of under-
pinning knowledge drawn from a range
of disciplines. Understanding the princi-
ples of effective movement control and
how skills are learned and refined are
vital aspects of the coaching process.
The use of skill acquisition strategies that
are supported by evidence can assist
practitioners in optimizing their training
provision and ensure the development of
more effective movement capabilities
that are robust under different conditions.
There are several established skill acqui-
sition strategies available for coaches to
use (8,12,17). With so many potential op-
tions, there may be some confusion as to
when andwhere these strategies aremost
appropriate. Furthermore, when pre-
sented with an athlete displaying techni-
cal errors, less experienced coaches may
not have a clear system through which
they can logically and systematically
apply strategies to correct him or her.
In this situation, it is intuitive to simply
tell the athlete what they did wrong, and
what they should do instead. This explicit
method of coachingmay not be themost
effective and may inhibit learning. Thus,
a greater critical understanding of the dif-
ferent approaches available for coaching
movement, and the utility of each, is war-
ranted to enhance athletic development
and optimize training transfer.
More recently, a dynamic systems–
based approach to S&C coaching has
been popularized, which favors the use of
constraints to facilitate learning (12).
Specifically, the coach manipulates the
environment, the task, or the athlete
directly to provide nonverbal (or implicit)
information to affect a positive change in
the movement outcome. The dynamic
systems approach allows for a more
individual understanding of movement
execution, where good or excellent
technique is athlete specific and can only
be appreciated within the context of that
individual’s anthropometry, training sta-
tus, and training history (11). This cul-
tural shift from didactic teaching to
athlete-centered support redefines the
role of the S&C coach from the provider
of esoteric knowledge to a constructor of
effective learning settings.
The purpose of this article is to present
a working model of error correction,
incorporating several skill acquisition
strategies in a logical structure (Figure 1).
The details and sequence of each com-
ponent of the model will be examined,
with a supporting rationale for their
inclusion. Practical examples are also
provided to demonstrate how the model
could be used to enhance the delivery of
movement skill education.
Address correspondence to Emily Cushion,
emily.cushion@stmarys.ac.uk.
KEY WORDS :
coaching science; constraints; dynamic
systems; effector dynamics; sequence rep-
resentation; skill acquisition
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ESTABLISHING THE START POINT
The first step required to begin the
process of correcting movement faults
is to establish and ask the relevant
questions. In the example of the model
presented here (Figure 1), these are as
follows: (1) Is the movement an error
or a mistake? (2) Was it a cause or
effect? and (3) What was the source
of the error? This step is critical to
ensure that the appropriate correction
strategy is implemented, optimizing
the coaching and movement outcome.
Before we consider these 3 questions,
it is worth reflecting on the relation-
ship between the technical model,
movement efficiency, effectiveness,
and safety. From this perspective,
coaches must appreciate the biome-
chanical benefits and risks associated
with any given movement strategy
when looking to identify movement
errors. For example, the technical
model of a deadlift requires the main-
tenance of a neutral spine throughout
the movement (2). However, during
extremely heavy deadlifting (i.e.,
powerlifting competition), the subtle
lordotic and kyphotic alignment of
the spine in the lumbar and thoracic
regions, respectively, is unlikely to be
maintained due to the hip extensor
musculature generating forces far
exceeding the erector spinae isomet-
ric capacity (16). This results in
a deviation away from the technical
model. The advantage of this strategy
is that it allows the athlete to reduce
the external hip flexion moment by
bringing the bar closer to the hip joint
(16), while using the passive struc-
tures, such as the posterior spinal lig-
aments, to contribute in spinal
stabilization (30). In this scenario,
observing the performance of the
movement as an error may be too
superficial, with the mechanical con-
straints of the movement demanding
a spinal flexion strategy for greater
performance. As such, if spinal flex-
ion range of motion (ROM) is not
exhausted, then the risks associated
with spinal flexion under load may
be mitigated while a greater perfor-
mance outcome is achieved (29).
Using this example, we can see how
this relationship between perfor-
mance, safety, and efficiency is com-
plex and that coaches should have
a strong biomechanical rationale for
specifying technical models for spe-
cific athletes.
QUESTION 1: ERROR OR
MISTAKE?
A mistake is an inconsistent devia-
tion from the expected technical
model. This might represent normal
variation in the execution of a move-
ment or from a lapse of concentra-
tion by the athlete. For example,
during a stiff-leg deadlift, the bar
may move away from the body in
the descent phase or when perform-
ing leg lowers, the athlete may move
into lumbar hyperextension. To char-
acterize these as mistakes, upon the
next repetition, the athlete would
correct this fault without any neces-
sary intervention from the coach.
Conversely, if the athlete made the
same movement fault on further
Figure 1. A proposed process of error correction for strength and conditioning
coaches.
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repetitions, this would be classified as
an error, potentially requiring an
intervention from the coach to cor-
rect. For the context of this article,
the focus will be placed on the pro-
cess after an error has occurred.
Consideration should be given to the
constraints of any given movement
when observing movement errors.
In the example of the athlete failing
to adhere to a strict bar path during
the stiff-leg deadlift exercise, the ath-
lete may not have sufficient resis-
tance for their system to consider
the bar path an important variable
in effectively executing the move-
ment. However, when load is added,
the internalinformation (i.e., propri-
oception) may then present as a stim-
ulus for an acute adaptation of the
movement strategy. With the addi-
tion of external load, the neuromus-
cular system may consider bar path
an important factor in successful per-
formance of the movement. This is
vital for coaches to consider with re-
gard to distinguishing movement er-
rors and mistakes because errors are
more likely to remain consistent
across different demands.
QUESTION 2: CAUSE OR EFFECT?
The second question to be asked is
whether the observed movement
fault is the effect of an earlier error
or the direct cause. To illustrate this
point, consider an athlete performing
a weightlifting movement such as
the snatch; the athlete is unable to
successfully catch the bar, and he
or she consistently loses the bar to
the front. Initially, it might appear
that the bar is moving forward of
the athlete during the second pull
(Figure 2). The coach must deter-
mine if it was an error occurring dur-
ing this phase of the lift or the result
of an error earlier in the movement. If
in the set position, the athlete already
had the bar too far away from his or
her body, this might lead to the bar
remaining away from the body
throughout the lift (Figure 2). With-
out identifying the cause of the error,
subsequent coaching strategies tar-
geted at enhancing the second pull
may be ineffective.
Expanding on this element, sequential
movement faults during a squat
pattern are common when one joint
segment fails to contribute sufficient
ROM to the movement. When ankle
dorsiflexion ROM is limited, compen-
sations at the hip and knee are likely
(23,26,32). In such instances, once
ankle dorsiflexion ROM has been ex-
hausted, the proximal joint segments
will compensate to achieve the move-
ment objective of lowering the athlete’s
center of mass. As such, coaches
should attempt to identify which seg-
ment is the cause of the movement
fault by observing the timing of the
movement errors.
QUESTION 3: WHAT IS THE
SOURCE OF THE ERROR?
Finally, it should be determined if the
movement deviation is a result of
a sequence representation fault or
a musculoskeletal limitation to deter-
mine the next steps the coach should
take. This information may already
be available from a previous muscu-
loskeletal and movement screen,
which allowed the coach to observe
how the athlete performs during
specified tasks. Or, it may be the case
that they have previously observed
this movement fault in other athletes
and through prior experience under-
stand what the limitation may be. In
Figure 2. Understanding sequential errors during a snatch. (A) A consistent inability to successfully catch the bar overhead may be
the result of an improper set position, leading to a disconnection between the body and bar during the second pull. (B)
When the set position is corrected, the bar and body are then subsequently better positioned during the second pull.
Coaching: Error Correction Process
VOLUME 39 | NUMBER 6 | DECEMBER 201786
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either case, if the coach is unsure of
what direction to take, the simplest
option is to follow the process illus-
trated in Figure 1. This increases the
utility of the model and provides
opportunities for its use as a diagnos-
tic tool. Once the answers to the
questions have been considered, the
coach should more fully understand
the basis of the observed movement
fault and can move to stage 2a or 2b.
USING THE MODEL
STAGE 2A—SEQUENCE
REPRESENTATION
Sequence representation refers to the
mental template of how the move-
ment should look, based on the tech-
nical model. As can be observed from
Figure 1, implicit strategies are
applied before explicit strategies for
aiding error correction. Implicit
coaching strategies are well evidenced
as being more effective for long-term
retention of skills and for transfer to
new contexts (27). Learning skills
through explicit methods has been
shown to be associated with a break-
down in skilled performance under
pressure, possibly due to an increase
in reinvestment processes (24,25).
Although there is a danger of thinking
in an oversimplified manner that
implicit methods are ubiquitously
“better,” there is value in initially
favoring the use of implicit coaching
methods over explicit, based on the
available evidence (47).
Implicit strategies have been identi-
fied as aiding skill development
through minimizing the athlete’s
attention to specific areas of the
movement error (27). Two commonly
used implicit verbal cueing techniques
are attentional focus manipulations
and analogies (22,48). There is a pleth-
ora of research examining the effec-
tiveness of different focus of attention
cues (48). An internal focus of atten-
tion directs the athlete’s awareness to
the movement process, whereas
external foci direct attention to the
movement outcome. For example, if
an athlete is performing a back squat,
an externally focused cue might be
“push the floor away” in the ascent
phase to enable an effective leg drive.
Alternatively, an internal cue for the
same example may be “forcefully
extend the knees.” The cumulative
body of evidence consistently indi-
cates that in both simple and complex
tasks, external focus of attention cues
maximize performance, facilitate
learning, and better support long-
term retention more than internally
referenced cues (48).
The use of analogies provides ath-
letes with information about how to
carry out a task, without explicit ref-
erence to the movement sequence
(22). For example, when performing
a jumping task, the coach may say
“think of your legs like tight coiled
springs” or for a sprint drill a coach
may say, “drive your legs like pis-
tons.” In both cases, the analogy pro-
vides an athlete with a mental picture
about what needs to happen, without
details about how to achieve it. An
additional point for the coach to con-
sider is not only the construction of
the cue but also the relevance of the
information contained to the athlete
(34). The message embedded in a ver-
bal cue may be misunderstood, or an
athlete may not be able to relate to
the information provided. It is there-
fore important that any cue provided
is individualized.
In the example of the model presented
in the current article, if, after providing
a verbal cue, there is a positive impact
on the athlete’s movement, the coach
does not need to move to the next
stage and can instead allow the athlete
the opportunity to practice the desired
skill under the original conditions. For
example, if the athlete performing leg
lowers continued to move into lumbar
hyperextension, the coach might pro-
vide a verbal analogy (e.g., “imagine
your lower back is glued to the floor”).
If on subsequent repetitions, the athlete
performs the movement without lum-
bar hyperextension, they are now able
to refine their ability to continuously
carry out the movement successfully.
However, if this is not the case,
manipulating the task or environmen-
tal constraints may be a suitable
next step.
A constraints-based approach to
coaching is designed to improve
the athlete’s movement skills by
manipulating the task, environment,
and/or musculoskeletal system (12).
It is often the case that if the envi-
ronment is manipulated, so too is the
task. For example, if an athlete is per-
forming a stiff-leg deadlift but is
unable to effectively hinge at the
hip during this movement, a coach
may decide to manipulate the envi-
ronment and have the athlete per-
form a block deadlift. Here, the
change in the environment also
changes the task to some degree,
but the goal of performing the hip
hinge pattern remains the same. An
additional example would be if an
athlete performs a tuck movement
during the descent in a squat, a coach
may change the environment (and
task) by prescribing a squat to
a box, as a methodof limiting the
depth of the descent.
It should be noted that manipulating
the environment or task will also alter
how the athlete’s neuromuscular sys-
tem interprets the movement. For
example, if an athlete demonstrates
limited depth during a squat, it may
be suggested that certain joint seg-
ment(s) do not possess the required
mobility. However, if the athlete lacks
the skill to perform the squat pattern
due to limited practice, excessive co-
contraction at each joint may prevent
their available ROM from being dis-
played to maintain balance and reduce
the threat of injury (10,40). To identify
if such strategy is present, a coach can
provide the athlete with additional sup-
port (i.e., holding on to a fixed pole
with the arms), reducing the skill de-
mands. If the athlete exhibits greater
ROM during the squat pattern, it is
likely that a deficiency in skill is present
(Figure 3). This can be confirmed with
isolated joint testing.
If minimal improvements are observed
in an athlete’s movement pattern when
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using an implicit coaching approach,
it is then suggested to use explicit
methods (Figure 1: stage 2a explicit
methods). This may begin in the
form of verbal cues, which can be
used to direct attention to poor pos-
ture or movement. For example, dur-
ing a stiff-leg deadlift, the athlete may
flex at the spine during the descent,
and the coach may then direct their
attention to this and simply tell the
athlete to straighten their back. If this
does not have a positive impact on
the resultant movement, alternative
explicit approaches can be used. In
this instance, the coach may choose
to provide a demonstration or use
kinesthetic correction methods.
Within the coaching science litera-
ture, demonstration has shown to
be a useful tool for enhancing
skill development (17). However,
caution should be applied because
the use of demonstration is not with-
out criticism. Demonstrations have
been argued to constrain athletes to
a narrow parameter of movement
execution, negatively impact motiva-
tion, and have the potential to reduce
movement efficiency by inadver-
tently transmitting irrelevant details
(17,43,44). Another explicit correc-
tion method uses kinesthetic feed-
back. Kinesthetic feedback uses the
information received from the senso-
rimotor system about the position
and movement of the body (31). A
coach may use this to correct an
error in spinal position during a dead-
lift, by physically reorienting the ath-
lete into the desired position or using
a wooden dowel placed along the
length of the spine, with instructions
to maintain contact at key anatomi-
cal locations (Figure 4).
In each of the approaches described
above, if the movement fault is cor-
rected to a satisfactory level, the ath-
lete can return to the original task,
allowing the coach to revaluate the
athlete’s performance. Of course, in
some instances, there will need to be
a period of practice to reinforce
the corrected movement. However,
if the athlete is still unable to perform
the task with an appropriate level of
technical competence, this may indi-
cate that it is not a sequence repre-
sentation error and could be
a musculoskeletal limitation.
STAGE 2B—MUSCULOSKELETAL
LIMITATION
When observing an athlete performing
a given task, coaches should be aware
that the source of an observed move-
ment error might be due to a limitation
in a fundamental physical ability. The
assumption of the strategies presented
in the previous section are that the ath-
lete simply does not “know” what they
are meant to do and that there is infor-
mation missing in the mental represen-
tation of the skill. In this case, the role
of the coach is to fill this gap, using
either implicit or explicit strategies or
by manipulating task and environmen-
tal constraints as a way of helping the
athlete understand how the movement
should be performed. However, it
might be the case that although the
Figure 3. The impact of task constraints on the musculoskeletal system. When asked to perform a squat, it might appear that the
limitation in squat depth is the result of inadequate joint mobility (A). However, manipulating the task by asking the
athlete to perform a squat while supported, the musculoskeletal system responds favorably, demonstrating a balance/
control issue, as opposed to a joint range issue (B).
Figure 4. Providing kinesthetic (tactile) feedback to an athlete (B), as an explicit method or correcting poor spinal position during
a stiff-leg deadlift (A).
Coaching: Error Correction Process
VOLUME 39 | NUMBER 6 | DECEMBER 201788
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athlete “knows” what they are supposed
to do, they just do not have the physical
capability to perform the movement.
Stage 2b of the model (Figure 1) out-
lines approaches to deal with move-
ment errors related to acute, chronic,
and fixed musculoskeletal limitations.
Athletes do not live in a bubble;
therefore, short-term physical condi-
tion is variable (18,37). Sleep, work,
nutrition, travel, and competition are
all factors influencing biophysical
capability (6,7,9). An awareness of
how these factors might be contribut-
ing to observed faults is important
when deciding which corrective strat-
egy to implement. Where many of the
strategies implemented in stage 2a
indirectly influence the musculoskele-
tal system, stage 2b involves direct
manipulation of the organism as an
approach to correct the movement
fault. Two commonly used, and well-
evidenced strategies to overcome
acute limitations are postactivation
potentiation (39,45) and warm-ups
(1,3). Although these approaches
may improve athletic performance in
a more global sense, there are times
a more targeted approach is required
for error correction.
The gluteal muscle group is responsi-
ble for several movements around the
hip joint. Localized contractile impair-
ment in the muscles of this group re-
sulting from short-term fatigue or
a period of unloading (e.g., during pe-
riods of extended travel) might nega-
tively impact on performance and
efficiency in a range of skills (20). As
such, so-called activation exercises are
often suggested to be included in
a more comprehensive and individual-
ized warm-up (19) or between working
sets of a specified skill. In either case,
“activation” exercises are typically low-
intensity therapeutic exercises, such as
prone plank holds with additional sin-
gle leg hip extension (33). The purpose
here is to acutely improve the contrac-
tile properties of a target muscle group,
allowing for improved performance,
movement quality, or both (14,33).
Of course, this tactic will only be ben-
eficial for musculoskeletal limitations
that are transient in nature. For chronic
insufficiencies, a more comprehensive
and long-term approach is required.
Rebound jumps are an effective
method of improving leg stiffness and
central drive (5,38,49). When the focus
is on improving stiffness, the overall
task requires minimizing both ground
contact time and compression of the
leg spring (41). An athlete who is
unable to meet these task requirements
during a drop jump because of
a sequence representation error might
see improvements if verbal instructions
emphasize being, “quick off the
ground.” But fundamentally, an ath-
lete’s ability to effectively perform drop
jumps hinges on their ability to apply
sufficient leg extension force to the
ground during brief contact periods
(4,36). There are 2 things to be consid-
ered here. First, the coach needs to
modify his or her expectation and, in
the short-term, understandthat the
athlete’s ground contact time will be
greater than is considered appropriate
for this exercise. Alternatively, they can
decrease the intensity of the exercise by
reducing the height of the drop (Fig-
ure 5) or regress to a drop and land task
by removing the propulsive phase of
the jump to develop eccentric strength.
In either case, the immediate expecta-
tion is modified, allowing the athlete
the opportunity to continue practicing.
At the same time as this task manipu-
lation, the coach will construct a suit-
able training intervention designed to
improve the physiomechanical profile
Figure 5. Manipulating task constraints as a method of modifying expectations in an athlete with a chronic musculoskeletal
limitation. (A) Initially, the athlete is unable to maintain the required level of vertical stiffness during a drop jump. (B) By
reducing the height of the drop, the athlete is now able to successfully perform this task (B).
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of the lower limb. After spending suf-
ficient time developing the underpin-
ning biomotor abilities, the athlete
will be able to return to the original
task and increase his or her chances
of performing the exercise competently
at the correct intensity.
Evolution through natural selection
requires genetic variation within
a population (21). This genetic varia-
tion interacts with the environment to
create physical and behavioral pheno-
types, which provide fitness benefits
for a given environment (46). Some
morphological variations are easily
seen when comparing anatomical dif-
ferences in athletes from different
populations (42) or even in athletes
playing different positions in the same
sport (e.g., the anthropometric differ-
ences between forwards and backs in
rugby union) (15). However, some
anatomical differences are not so easy
to identify, such as femoral neck-shaft
angle or humeral retroversion (13,28).
This anatomical variation might influ-
ence the coaches’ exercise selection
for a sporting population. Equally,
where an individual’s anthropometry
prevents adherence to a given techni-
cal model, it falls upon the coach to
modify their expectations and subse-
quently the requirement of the task.
This might involve allowing for devi-
ation from the expected technical
model, for example, reduced squat
depth or altered foot alignment in
the transverse plane. Alternatively,
the coach may need to select a differ-
ent method of achieving the required
training outcome, such as substituting
squats with heavy-weighted sled
pushes for the development of leg
strength. Similarly, a series of regres-
sion and/or lateralization alternatives
should be planned, so the athlete can
still derive an appropriate training
stimulus while not sacrificing techni-
cal execution or the desired adapta-
tion (35).
CONCLUSION
A range of established skill-learning
approaches are available when
coaching athletes. However, a clear
system through which correction
strategies can be logically and sys-
tematically applied is warranted to
maximize coaching effectiveness and
training transfer. This article presents
a model of error correction incorpo-
rating several skill acquisition strate-
gies with a focus on athlete-centered
learning.
After correctly identifying the nature
and source of the observed movement
fault, coaches are recommended to ini-
tially adopt an implicit approach,
manipulating attentional focus, using
analogies or by manipulating of the
task and/or environmental constraints.
If this approach is not effective in
enhancing movement proficiency after
a period of trial and error, it is then
suggested to use explicit methods to
direct their attention to poor posture
or movement, through verbal cuing,
practical demonstrations, or kines-
thetic correction. Coaches should also
be aware that the source of an
observed movement error might be
due to a musculoskeletal limitation
where the athlete does not have the
physical capability to perform the
movement. These limitations can be
acute, chronic, or fixed, and coaching
strategies here may involve direct
manipulation of the organism or by
modifying the expectations of the
athlete.
A key feature of the model is that
when applying each correction strat-
egy, if the movement fault is corrected
to a satisfactory level, the athlete can
return to the original task. This allows
the athlete to practice and refine the
skill and allows the coach to revaluate
the athlete’s performance and deter-
mine if further interventions are
required and if so, using what
approach.
Conflicts of Interest and Source of Funding:
The authors report no conflicts of interest
and no source of funding.
ACKNOWLEDGMENTS
The authors thank Andreas Fourou-
clas and Phil Price for their assistance
with the images in this article.
Emily Cushion
is a lecturer in
Strength and
Conditioning at
St Mary’s
University.
Louis Howe is
a lecturer in
Sports Rehabili-
tation and Bio-
mechanics at
University of
Cumbria.
Paul Read is an
athlete health
and performance
research scientist,
Aspetar.
Adam Spence
is a strength and
conditioning
coach and per-
formance
scientist.
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Coaching: Error Correction Process
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