MOTOR LEARNING OUTCOMES OF OVERHAND THROWING USING VISUAL AND
VERBAL CUES WITH COLLEGE AGED NOVICES

By:
John S. Nemeth IV, B.S.
East Stroudsburg University of Pennsylvania

A Thesis Submitted in Partial Fulfillment of
The Requirements for the Degree of
Master of Science in Exercise Science
To the office of Graduate and Extended Studies of
East Stroudsburg University of Pennsylvania

August 9, 2019

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ABSTRACT
A Thesis Submitted in Partial Fulfillment of the Requirements for the Degree of Master
of Science in Exercise Science to the Graduate College of East Stroudsburg University of
Pennsylvania.
Student’s Name: John S. Nemeth IV
Title: Motor Learning Outcomes of Overhand Throwing Using Visual and Verbal Cues
with College Aged Novices
Date of Graduation: August 9, 2019
Thesis Chair: Matthew Miltenberger, Ph.D.
Thesis Member: Gavin Moir, Ph.D.
Thesis Member: Brandon Snyder, M.S.
Thesis Member: Shala Davis, Ph.D.
Abstract:
Previous studies have shown that focus of attention, in the form of instruction and
feedback, is highly effective in increasing learning (Shafizadeh, 2013). Cues facilitate the
learning of motor skills (McCullagh, Stiehl, & Weiss, 1990; Masser, 1993; Zetou,
Tzetzis, Vernadakis, & Kioumourtzoglou, 2002) because they direct the performer's
attention to regulatory conditions in the environmental context and also to the key
movement components of a skill (Shafizadeh, 2013). Cueing technique has frequently
been shown to be effective in overcoming the potential problems associated with visual
modelling in novice performers (Shafizadeh, 2013). This is also shown in verbal
analogies as well. The purpose of the analogy is to make the performer focus on the
movement instead of individual body parts such as the elbow or wrist during a throw.
Studies demonstrated that focusing attention on movement goals (external focus) rather
than on movements themselves (internal focus) led to faster learning (Shafizadeh, 2013).
The current investigation is designed to analyze the learning benefits of visual and verbal
external cueing incorporated into the overhand throwing routine of a novice while also
examining kinematic changes and confidences of throwing. The investigation will
include 15 male and female subjects, aged between 19-28 years of age. The testing
involves 45 throws, as well as confidence scoring, over 3 testing days. 15 throws will be
performed each testing session and separated into 3 sets of 5 throws with a 2-minute rest
period between sets. The first session will serve as a pre-test, the second session will
serve as the testing session, and the third session will serve as the retention test 48 hours
following the second session. The retention test allows to establish whether learning has
occurred over the course of the investigation.

TABLE OF CONTENTS
LIST OF TABLES ...………………………………………………...………………….. vi
LIST OF FIGURES …………………………………………………...…………..….... vii
Chapter
I.

INTRODUCTION……………………………………………………………...... 1
Purpose……………………………………………………………...………….... 7
Null hypothesis…………………………………………………………………... 7
Operational definitions…………………………………...…………………...…. 8
Delimitations……………………………………………...……………………... 9
Limitations……………………………………………………...……………….. 9
Summary……………………………………………………...…………………. 9

II. LITERATURE REVIEW………………………………………………………. 11
Confidence scoring……………………………………………………………... 13
Unconscious learning………………………………………...………….……... 14
Attentional focus………………………………………………...……………... 15
External focus…………………………………………………………………... 17
Feedback………………………………………………………………………... 18
III. METHODOLOGY……………………………………………………………... 20
Subjects………………………………………………………....………………. 20
Subject demographics.………………….………………………………………. 21
Subject recruitment………………………………………………………………21
Procedures………………………………………………………………………..21
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Flow chart………………………………………………………………………..21
Detailed procedures……..…………………………………………………. ….. 22
Pre-test………………………...............................................................................25
Testing………………………………………………………………………...…25
Verbal cues used…………………………………………………………………26
Retention…………………………………………………………………....……26
Data collection…………………………………………………………………...27
Data & measures…………………………………………………………………27
IV. RESULTS………………………………………………………………………. 30
V. Discussion………………………………………………………………………. 37
APPENDICES……………………………………………………………….............. 42
REFERENCES………………………………………………………………………. 44

v

LIST OF TABLES
Table
1. Table 1…………………………………………………………………………... 31
2. Table 2…………………………………………………………………………... 31
3. Table 3…………………………………………………………………………... 32
4. Table 4…………………………………………………………………………... 32
5. Table 5…………………………………………………………………………... 32

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LIST OF FIGURES
Figure
1. Figure 1…………………………………………………………………………. 19
2. Figure 2…………………………………………………………………………. 27
3. Figure 3…………………………………………………………………………. 33
4. Figure 4…………………………………………………………………………. 34
5. Figure 5…………………………………………………………………………. 35
6. Figure 6…………………………………………………………………………. 36
7. Figure 7…………………………………………………………………………. 39

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Chapter I
Introduction
Conveying the proper information to athletes to create a motor performance is a
task that many coaches do not use properly or understand. A majority of coaches prescribe
their athletes detailed instructions on how to use the perfect movement to perform a skill.
An example of this would be a baseball coach trying to correct a pitcher that throws
sidearm. What the coach does not understand that as long as that pitcher is successful and
consistent at throwing a strike, that is the perfect throwing motion for the pitcher. The
overhand throw is a motor skill of great complexity involving the entirety of the body to
create a kinetic chain that begins with the legs and then progresses to the pelvis, trunk, and
finally ending with the wrist and fingers. The torque from the pelvis and trunk pulls the
proximal to distal portions of the throwing arm to create a ballistic motion to propel the
baseball forward to its intended target (Fortenbaugh, 2011). In baseball making an accurate
throw is a crucial portion of the game and an asset that all skilled players must possess; this

1

skill being most important to be a successful pitcher (Seroyer, S. T., Nho, S. J., Bach, B.
R., Bush-Joseph, C. A., Nicholson, G. P., & Romeo, A. A. 2010). Theoretically, an
individual’s maximum pitching velocity potential is a product of optimal pitching
mechanics. The notion of optimal pitching mechanics for anyone is a concept that is
difficult to address due to the dynamic and complex nature of the movements involved in
throwing and the inherent differences in the anatomical, neuromuscular, and physiological
makeup of each individual (Seroyer, S. T., Nho, S. J., Bach, B. R., Bush-Joseph, C. A.,
Nicholson, G. P., & Romeo, A. A. 2010). A pitcher’s maximal velocity is indicative of
kinematics, kinetics, and relative timing of segmental interactions that lead to effective
transfer of momentum to the baseball. Slight changes in a pitcher’s mechanics may result
in higher or lower ball velocity. When analyzing baseball throwing, studies have reviewed
the mechanics and kinematics of overhand throwing and discovered that the role of the
trunk and elbow flexion torque, shoulder proximal force, and elbow proximal force were
the only kinetic parameters significantly associated with increased ball velocity (Stodden,
et al., 2005). Coordinated lower extremity muscles (quadriceps, hamstrings, hip internal
and external rotators) provide a stable base for the trunk (core musculature) to rotate and
flex (Seroyer, S. T., Nho, S. J., Bach, B. R., Bush-Joseph, C. A., Nicholson, G. P., &
Romeo, A. A. 2010). The rotation of the pelvis, torso, and trunk forward tilt within the
kinetic chain gives the thrower the torque and momentum to throw the ball at increased
velocities (Stodden, et al., 2001). The extremely rapid rate of this motion makes assessment
difficult. The time elapsed between front foot contact and ball release is only 0.145
seconds, followed by an additional half second for the ball to reach home plate (Seroyer,
S. T., Nho, S. J., Bach, B. R., Bush-Joseph, C. A., Nicholson, G. P., & Romeo, A. A. 2010).

2

Maximum humeral internal rotation velocity during throwing may reach 7500 to 7700
degrees per second (Seroyer, S. T., Nho, S. J., Bach, B. R., Bush-Joseph, C. A., Nicholson,
G. P., & Romeo, A. A. 2010). This is an attribute that a novice does not possess and is
usually taught through self-exploration. It is plausible that novice learners can be guided
without prescribing movements and enhance the self-exploration/self-organization process
and produce consistently accurate throws as well as increasing velocity.
Visual and verbal cueing is a form of direction and feedback to help with skill
acquisition and obtain performance proficiency. The transmission of augmented
information to the learner, in the form of verbal instructions or visual demonstrations, has
been the primary concern for motor learning theorists for many years (Newell, Morris, &
Scully, 1985). This study will compare the effectiveness of visual and verbal cueing when
teaching novices movement patterns of increasing complexity to efficiently use the kinetic
chain to achieve peak velocity and accuracy. Using the constraints led approach, we can
redefine motor learning as an ongoing dynamic process involving a search for stabilization
of specific, functional movement patterns across the perceptual-motor landscape as each
individual adapts to a variety of changing constraints (Davids, et al., 2008). The
Constraints-Led Approach is defined as the simple proposition that the coordination and
control of movements emerge from the confluence of constraints associated with the
organism, the environment, and the task (Davids, et al., 2008).
Providing small verbal cues, we enhance the subject’s ability to interpret their
constraints, affordances and perception. When providing visual cues, the subject is aided
with the process of observational learning by allowing the subject to learn from others’
mistakes and successes. Observational Learning is the process of a person assimilating and

3

sometimes adopting or replicating the behavioral patterns and actions of others as a direct
consequence of observing those behaviors (Ashford, Bennet, & Davids, 2006) (Davids, et
al., 2008). Findings of visual perception research on biological motion concerning what
information is perceived from demonstrations have been conceptually linked with Newell’s
(1985) framework of motor learning stages (Al-Abood, Davids, Bennett, 2001). During
skill acquisition, early learning requires the search for and assembly of a functional
coordination pattern. In a laboratory setting where a pitcher would not be anticipating a
batter to hit the pitch, the pitcher’s environment would be considered stable and thus a
closed motor skill (Moir, G., 2016). Expert performers are able to select and adopt relevant
information from a context (e.g., an opponent's body) and disregard irrelevant cues better
than novice performers ((Williams & Davids, 1998; Ward, Williams, & Bennett, 2002)
Shafizadeh, 2013). Skill acquisition then becomes the ongoing process of attaining
functional movement task solutions to satisfy the goal of motor skills (Davids, et al., 2008).
The skill acquisition process in this study will be aided through external verbal and nonverbal ques. Previous studies have shown that focus of attention, in the form of instruction
and feedback, is highly effective in increasing learning and these studies demonstrated that
focusing on movement goals (external focus) rather than on movements themselves
(internal focus) led to faster learning (Shafizadeh, 2013). A skilled performance is
characterized by high levels of movement effectiveness and efficiency (e.g., Guthrie, 1952)
(Wulf, G., 2013). Through guided self-exploration, subjects can discover the most efficient
movements to perform the tasks at hand with the given constraints and change their
perceptual attunement. Since the human body is seen as a complex system that has many
independent components working at different structural and functional levels, therefore the

4

actions the body need to be coordinated and controlled to be successful (Moir, G., 2016).
These independent motor systems are represented by Degrees of Freedom (DOF). In order
to successfully complete the task of overhand throwing, the subject must release and
organize their DOF, thus coordinating their motor system (Moir, G., 2016). The external
cues provided are aimed to aid novices in releasing and coordinating their DOF.
Internal and external attentional cues have been compared in many studies and have
been shown to differ between novices and experts. When using an external attentional
focus, an athlete will focus on variables external to the body and in particular to the
outcome of movements that they are performing (Wulf, G., 2013). Conversely, when using
an internal attentional focus, an athlete focuses on the variables associated with their body
and movement itself (Wulf, G., 2013). Studies have provided converging evidence that an
external focus of attention speeds up the learning process so that a higher skill level –
characterized by both increased effectiveness and efficiency – is achieved sooner (Wulf,
G., 2013 (Wulf, 2007b)). In this study we will be using external attentional focused ques
because it has been shown to be the most effective. An external attentional focus most
likely rules out the constraint imposed on the movement by an internal attentional focus;
an internal focus might potentially interfere with the natural self-attentional focus
organizing properties associated with the motor system that hinder the acquisition of a
functional movement task solution (Southard, 2011). In general, verbal instructions that
promote an external attentional focus have been shown to be more effective in promoting
learning (as determined by retention and transfer tests) (Wulf, G., 2013). These instructions
contain terms relating to the outcome of the movement rather than referencing specific
body parts, as this would be too prescriptive. Other researchers have supported the use of

5

biomechanical analogies in the verbal instructions presented to the athletes (Lam, Maxwell,
& Masters, 2009). Such analogies reduce the prescriptive nature of the instructions and
allow the natural self-organizing tendencies of the motor system to emerge (Moir, G.,
2016). Subjects in the visual cuing group will be using observational learning to construct
their motor coordination pattern. Observational learning by watching a model, in this case
a video, will provide relative motion information to the learner that would not necessarily
be present in verbal forms of instructions (Moir, G., 2016). This is important in the early
stages of learning when the learner is assembling his or her coordination pattern and has
been shown to result in in a more rapid acquisition of an appropriate coordination pattern
(Sakadjian, Panchuk, & Pearce, 2014). These cues will be used to aid the process of
Implicit learning externally. Learning is defined as a relatively permanent improvement in
performance and is assessed through the use of retention and transfer tests (Magill, 2011).
Implicit learning occurs when the athlete accumulates task-relevant information without
conscious awareness of what has been learned (Moir, G., 2016). Implicit learning has been
shown to be resistant to factors including anxiety, emotions, and changes in environmental
constraints that act to perturb the learned movements (Moir, G., 2016 (Masters & Poolton,
2012)). This study will add to the body of literature suggesting the avoidance of motor
skills being taught in an explicit and prescriptive manor and instead to promote selfexploration.
In order to assess the learned skills of the subjects they will need to have a retention
test. A retention test entails the administration of a test after a period of time during which
the performer has not been practicing the skill (Moir, G., 2016). The period of abstinence
from practice allows for the dissipation of other factors that allow the performance level to

6

be determined (Magill, 2011). This will test the adaptability of the skill learned by the
subject and establishes whether learning has occurred or not.
Consequently, the investigation at hand is designed to compare the subject motor
learning outcomes of accuracy, velocity, and kinematics of shoulder internal and external
rotation by using verbal and non-verbal external cues to promote implicit learning. The
perfect movement pattern is not the aim for the subjects. The aim for the subjects is to find
the coordination pattern the provides them with the most consistent success rate.
Purpose
1. The aim of this study is to compare the kinematic outcomes of using visual and
verbal cueing.
2. Examine new methods to educate novice performers to overhand throw.
3. Create a consistent pattern of accuracy & ball velocity with novice throwers.
Null Hypothesis
1. There will be no statistically significant difference between visual and verbal
cueing groups in change in velocity and accuracy
2. There will be no significant difference in accuracy between verbal and visual
groups
3. There will be no significant difference in velocity between verbal and visual groups
4. There will be no significant difference in confidence between verbal and visual
groups
5. There will be no significant difference in kinematics between visual and verbal
groups

7

6. Using visual and verbal cuing will have no effect on the subject’s performance and
learning
Operational Definitions
1. Verbal Cues – prompt phrases or words used to help subject find movement
patterns
2. Visual Cues – video used to help subject find movement patterns through
observation
3. Anchoring bias (Confidence score; 0-5) – Persuasive bias in which decision
makers are influenced by random or uninformative numbers or starting points
4. High anchor – Independent variable, use of a high number to influence subject’s
ability to estimate
5. Low anchor – Independent variable, use of a low number to influence subject’s
ability to estimate
6. Observational Learning - the process of a person assimilating and sometimes
adopting or replicating the behavioral patterns and actions of others as a direct
consequence of observing those behaviors
7. Inexperienced/Novice Thrower – no participation in organized sports involving
overhand throwing
8. Degrees of Freedom (DOF) – Each independent component of the human motor
system
9. Target – 6 quadrant target 20 feet from subject

8

Delimitations
1. Subjects are aged 18-24 years
2. Subjects are novice in the skill of overhand throwing
3. Subjects will be free from any upper body musculoskeletal injury over the past 12
months
Limitations
1. Subject’s focus and coordination on task at hand
2. Subject adherence to the program
3. Subject fatigue
4. Distance available to throw from lab constraints
5. Ability of subject to throw at a distance
6. Number of subjects
Summary
The study of external cueing methods of analogy and observational
learning has gained attention due to the realization that humans learn motor tasks in
numerous different ways. Previous studies (i.e., Southard, D.,2011) have shown that
external cues, as opposed to internal cues, are superior in the learning process of
improving throwing pattern and changing kinematics to increase throwing velocity. In
explanation, an instruction given should be presented to promote a subject’s focus on the
task execution and outcome (external), rather than focusing on the motion of a specific
body part (internal). When providing instruction for novices, the external cues provided
should be relevant to executing techniques. Instructions provide task-relevant information

9

to learners that can alter their intention and channel their search for an appropriate
movement solution ((Newell & Ranganathan, 2010) Moir, G., 2016). Therefore,
instructions represent a form of informational constraint (Moir, G., 2016).

10

Chapter II
Literature Review
The purpose of this study was to investigate the effects of verbal and non-verbal
external cues on overhand throwing accuracy, velocity, kinematics, as well as a retention
test, on inexperienced overhand throwers. This chapter will discuss literature related to
the topic of overhand throwing and motor learning. The scholarly research that has been
reviewed within the following chapter was used to design the study from the conclusions
of others research and the factual data of the cognitive human motor system.
The subject procedures from Southard, D. (2011). Attentional focus and control
parameter: Effect on throwing pattern and performance. Research Quarterly for Exercise
and Sport for testing criteria to find substantial evidence using 30 subjects, throwing 15
times a trial, and receiving feedback every 5 throws which will reduce the risk of injury
and provide statistically significant results. The 1 hypothesis that Southard proposed was
st

to compare the effect of an internal focus of attention, external focus of attention, and/or

11

scaling up a control parameter (velocity of throw) on changes in the throwing pattern
during practice and at retention (following 1 week of no practice). The results of this
experiment show that external cues are superior in the learning process of improving
throwing pattern and changing kinematics to increase throwing velocity, but subjects who
received feedback every 5 throw had the information become redundant. These results
th

support the claim of using 15 throws for each subject and using external cues to change
throwing patterns but the cues that will be used every 5 throw will be different than the
th

one that they were previously given to avoid becoming redundant. Southard’s second
experiment’s hypothesis is that when novice performers practice a skill, there is a strong
likelihood that the individual’s motor pattern will change (Hatze, 1971). The implication
is that changes in performance are accompanied by changes in motor pattern that produce
an increase in movement efficiency (Sparrow, 1983). This hypothesis states the reasoning
of implying that a novice motor coordination will change from using external cues and
practice and will have an increase of movement efficiency and accuracy.
A motor task is but a small portion of a motor system that is regarded as a
complex system. A complex system is defined as any system that consists of many
independent components operating at different structural and functional levels; The
human motor system can be regarded as a complex system whose independent
components (Degrees of Freedom) need to be coordinated and controlled to successfully
execute the movements required to accomplish the goal of a motor skill (Moir, G., 2016).
The human body is characterized a large amount of Degrees of Freedom that need to be
coordinated to be successful at completing motor tasks. The coordination and control of
Degrees of Freedom is achieved through the formation of coordinative structures, which

12

is defined as a temporary organization of Degrees of Freedom that emerges through the
process of self-organization under constraint (Turvey, Fitch, & Tuller, 1982). The process
of self-organization associated with complex systems was a well-documented
phenomenon in physical and chemical systems long before any attempts were made to
empirically verify its presence in a system of human movement coordination (Schoner &
Kelso, 1998). Self-organization implies spontaneous pattern generation as a consequence
of the interaction of a very large collection of Degrees of Freedom that may adapt in
response to changing internal and external conditions, by adopting coordination patterns
without any explicit prescription of the emergent pattern (Schoner & Kelso, 1988).
Confidence Score: Anchoring
Before each trial, subjects will be asked how many times out of 15 throws they
will hit the center of the target. This concept is known as anchoring and is defined as
persuasive bias in which decision makers are influenced by random or uninformative
numbers or starting points. The subject will rely on the initial score that they believed
they would produce, use it as use it as an arbitrary focal point or benchmark, “anchor”
themselves to it, and attempt to reach or beat the score. Anchoring seems especially
relevant to a bargaining setting such as the purchase of residential real estate, where (1)
the fair market value (FMV) of the piece of property is not objectively determinable, and
(2) a bidding process is used to arrive at the property’s actual selling price. The first value
of the bidding process- the seller’s asking or listing price-might serve as an anchor,
effectively determining the neighborhood of appropriate prices for subsequent price
negotiations (Lam, W. K., Maxwell, J. P., & Masters, R. 2009). In negotiations,
anchoring is setting a boundary that outlines the basic constraints for a negotiation. The

13

anchoring effect is where we set our estimation for the true value of the item at hand
(Tversky, A., & Kahneman, D. 1974). In addition to the initial research conducted by
Tversky and Kahneman, multiple other studies have shown that anchoring can greatly
influence the estimated value of an object (Orr, D., & Guthrie, C. 2005). If a subject
estimates that they will only hit the center of the target 7 times or less out of the 15
throws, this is considered a low anchor, and if the subject estimates that they will hit the
target greater than 7 times out of 15 throws, this will be considered a high anchor. The
outcomes can be explained by the Insufficient Adjustment Theory and the Numeric
Priming Theory. The Insufficient Adjustment Theory, which is defined as anchoring
because we fail to adjust and first focus on the anchor and then make a series of dynamic
adjustments toward their final estimate. Because these adjustments are insufficient, the
final answer is biased toward the anchor (Orr, D., & Guthrie, C. 2005). This would mean
that a subject focused on the anchor too much and made adjustments that made the
thrower throw closer to the anchor rather than exceeding the number that they have
chosen out of 5. In previous motor learning studies, anchoring has been shown that many
subjects will end up with a successful amount of trials that almost match the anchor that
they had chosen.
This confidence scoring is also used to assess he subjects interest in the task at
hand. During the learning process, research has shown that learners must have a 50%
success rate in order to keep the subjects interested in learning and to have the motivation
to continue with the task. If a subject has a low success rate, it is most likely that they
will no longer be interested in the task and provide less effort.

14

Unconscious learning
The learning process that this study will abide is the Constraints-Led Approach
which is based upon non-linear pedagogy. This is a learner-centered approach to skill
acquisition that uses task and environment to develop skill acquisition. Coordination and
control of movements emerge from the confluence of constraints associated with the
organism, the environment, and the task (Davids, et al., 2008). A constraint is defined as
a variable that limits the configuration of the motor system, guiding the movements of the
performer as he or she executes a motor skill (Newell, 1986). Organismic constraints are
associated with the performer and include the physical properties of the motor system as
well as biomechanical and logical variables (Moir, G., 2016). According to Schoner and
Kelso (1988), the many possible coordination patterns of a movement system will
eventually converge around a limited set of stable coordination patterns (Moir, G., 2016).
This convergence is known as an attractor state. These attractor states can be illustrated
on a topological graph of the perceptual motor workspace as wells. The perceptual motor
workspace contains the constraints, information of the motor skill, and the intrinsic
dynamics of the individual subject for the motor skill that is to be learned. The goal of
unconscious learning is for the subject to self-explore their perceptual motor workspace
and discover new information to complete the motor task. The constraints that are given
to subjects can be changed in order to help with the learning process and change intrinsic
dynamics. Providing different analogies of movement or different visual demonstrations
may provide new information and allow a subject to perceive the task in a new way.

15

Attentional Focus
The attentional focus of an athlete refers to the location of the sources of
information to which the athlete attends when executing a motor skill (Moir, G., 2016). In
this study the subjects are provided 2 things that they are able to attune themselves to
during the throwing trials. These may include the target in which they are throwing at and
either the video shown, or the verbal analogies spoken to them. In this case the purpose of
the cues given are to encourage an external attentional focus. As previously mentioned,
adopting an external attentional focus is more effective during learning than an internal
attentional focus which focused on the movement itself (Wulf, G., 2013). Research has
shown that focus of attention of movement goals (external focus) contrasting focus on
movements themselves (internal focus) leads to increased rates of learning. Associating
observational learning and attentional focus for the purpose of teaching motor skills is
imperative for multiple reasons. Firstly, the focus of attention has been used in previous
studies for other methods of explicit learning as a form of instruction or feedback and it is
important to examine its functionality in other forms of explicit learning such as
demonstration because it can facilitate the acquisition of a movement idea before
attempting to perform a skill (Shafizadeh, 2013). Secondly, cognitive mediating theory
does not consider the focus of attention during the acquisition stage of observing a model
(Shafizadeh, 2013). Lastly, according to the specificity of learning hypothesis (Proteau,
1992), compatibility between the technique of the skill presentation and the learning
context is important in the learning process (Shafizadeh, 2013). The verbal instruction
and feedback provided to a subject, in terms of sensory modality, may not meet the
attentional demands for the motor skill at hand. A visual representation may be best

16

suited for certain situation because it relies upon visual sensory instead of verbal
interpretation of a movement description or analogy. On the other hand, the focus of
attention during a demonstration requires overt attention, whereas verbal instruction and
feedback mostly require covert attention (Shafizadeh, 2013).
Visual and verbal provisions of instruction and feedback have been shown to be
successful. Although some subjects may be more proficient with one way of learning
than the other. Providing information that a subject may not perceive correctly may
perturb the learning process by possibly causing the subject to think internally rather than
externally.
External Focus
External attentional focus is defined as having an athlete focus on variables
external to their body and in particular outcome to the of the movements they are
performing (Wulf, G., 2013). When defining an internal attentional focus, an athlete
focuses on variables associated with their body and movement itself (Wulf, G., 2013). An
external attentional focus likely rules out the constraint imposed on the movement by an
internal attentional focus; an internal focus might potentially interfere with the natural
self-organizing properties associated with the motor system that hinder the acquisition of
a functional movement task solution (Southard, 2011). Southard (2011) discovered that
providing the same verbal ques during a 15-pitch throwing trial becomes redundant. In
order to limit redundancy, 3 different verbal ques will be used for one subject. This will
satisfy learning-transfer experiences of different subjects because not all subject will
share the same life experiences as others and can better relate to certain analogies of
throwing (Rosalie, S. M., & Müller, S. 2012). Providing a larger range of analogies will

17

provide the subject with a broader range of successful responses (Rosalie, S. M., &
Müller, S. 2012). As well as avoiding redundancy for this study, redundancy of cueing
for further research will be considered as well by asking subjects after the pre-test trial
what they think about during the pitching trial. This will help tailor ques to specific
athletes and create new ques for further research and provide knowledge of selfmotivation during subject activity.
Feedback
Feedback is the information that is provided to the learner after the performance
of a motor skill in relation to the task goal (Moir, G., 2016). During the testing process
for this study, the only feedback that will be provided to the subject will be from
themselves or the cueing that they receive. This is contingent upon how they react to the
cues and apply them to their motor skills through the learning process. The outcome of
the movement relative to the goal of the motor skill, known as knowledge of results,
provides feedback to the performer (Moir, G., 2016). The knowledge of results that the
subjects will have will be hitting or missing the target they are throwing at. Due to the
fact the subjects do not receive feedback on their movements this cannot be considered
knowledge of performance.

18

Figure 1: Perceptual Motor Skill Framework

Rosalie, S. M., & Müller, S. (2012).
Expert performers are able to select and adopt relevant information from a context (e.g.,
an opponent's body) and disregard irrelevant cues better than novice performers (Williams &
Davids, 1998; Ward, Williams, & Bennett, 2002).

19

Chapter III
Methodology
The purpose of this study is to investigate the effects of verbal and visual external
cuing on inexperienced overhand throwing accuracy and velocity using a regulation
tennis ball. This chapter will discuss the collection and analysis of data that was collected
in the research laboratory of The East Stroudsburg University of Pennsylvania.
Subjects
This study included 15 healthy college aged (18-28 years) males and females.
Inclusion criteria consists of having no prior experience with overhand throwing.
This means that the subject cannot have participated in organized sports that required
overhand throwing.
Exclusion criteria consists of the subjects having prior injury or surgery to the
throwing arm. Other injuries that could affect the motion of throwing will also exclude the
subject from testing.

20

Subject Demographics
15 subjects that included 8 males and 7 females. The average subject age being 23 ± 2.1
years.
Subject Recruitment
Subjects will be recruited from classrooms within the exercise science department
and were asked to fill out a questionnaire asking them of their age, training status, sports
played currently and or previously, right or left-handed throwing dominance, and previous
injuries or abnormalities.
Procedures
The following procedures were conducted after recruiting and include 3 days of
testing. The first day of testing was used to establish the baseline for subjects and for group
placement. The second day of testing was used to provide visual or verbal instruction to
aid in the process of learning. The third and final day of testing was a retention test that
was done 48 hours after the previous session to establish is learning had occurred.
Flow Chart
Pre-test
•Par-Q
•Warm up
•Confidence score
•5 throws
•2 min rest
•Confidence score
•5 throws
•2 min rest
•Confidence score
•5 throws

Testing

Retention

•Warm up
•Confidence score
•Cue given
•5 throws
•2 min rest
•Confidence score
•5 throws
•2 min rest
•Confidence score
•5 throws

21

•Warm up
•Confidence score
•5 throws
•2 min rest
•Confidence score
•5 throws
•2 min rest
•Confidence score
•5 throws

Detailed Procedures
1. Group 1: Control
a. Pretest
i. Par-Q
ii. Subject warm up
iii. Subject asked confidence score
iv. Subject instructed to throw the ball at the target 5 times
v. Subject 2-minute rest period
vi. Subject asked confidence score
vii. Subject instructed to throw the ball at the target 5 times
viii. Subject 2-minute rest period
ix. Subject asked confidence score
x. Subject instructed to throw the ball at the target 5 times
xi. Subject asked what they think about when throwing the ball
b. Testing
i. Subject warm up
ii. Subject asked confidence score
iii. Subject instructed to throw the ball at the target 5 times
iv. Subject 2-minute rest period
v. Subject asked confidence score
vi. Subject instructed to throw the ball at the target 5 times
vii. Subject 2-minute rest period
viii. Subject asked confidence score
ix. Subject instructed to throw the ball at the target 5 times
c. Retention Test
i. Subject warm up
ii. Subject asked confidence score
iii. Subject instructed to throw the ball at the target 5 times
iv. Subject 2-minute rest period
v. Subject asked confidence score
vi. Subject instructed to throw the ball at the target 5 times
vii. Subject 2-minute rest period
viii. Subject asked confidence score
ix. Subject instructed to throw the ball at the target 5 times
2. Group 2: Visual
a. Pretest
i. Par-Q
ii. Subject warm up
iii. Subject asked confidence score
iv. Subject instructed to throw the ball at the target 5 times
v. Subject 2-minute rest period
vi. Subject asked confidence score
vii. Subject instructed to throw the ball at the target 5 times
viii. Subject 2-minute rest period
ix. Subject asked confidence score

22

x. Subject instructed to throw the ball at the target 5 times
xi. Subject asked what they think about when throwing the ball
b. Testing
i. Subject warm up
ii. Subject asked confidence score
iii. Subject shown short video clip of over hand thrower
iv. Subject instructed to throw the ball at the target 5 times
v. Subject 2-minute rest period/subject shown short video clip of over
hand thrower
vi. Subject asked confidence score
vii. Subject instructed to throw the ball at the target 5 times
viii. Subject 2-minute rest period/subject shown short video clip of over
hand thrower
ix. Subject asked confidence score
x. Subject instructed to throw the ball at the target 5 times
c. Retention Test
i. Subject warm up
ii. Subject asked confidence score
iii. Subject instructed to throw the ball at the target 5 times
iv. Subject 2-minute rest period
v. Subject asked confidence score
vi. Subject instructed to throw the ball at the target 5 times
vii. Subject 2-minute rest period
viii. Subject asked confidence score
ix. Subject instructed to throw the ball at the target 5 times
3. Group 3: Verbal
a. Pretest
i. Par-Q
ii. Subject warm up
iii. Subject asked confidence score
iv. Subject instructed to throw the ball at the target 5 times
v. Subject 2-minute rest period
vi. Subject asked confidence score
vii. Subject instructed to throw the ball at the target 5 times
viii. Subject 2-minute rest period
ix. Subject asked confidence score
x. Subject instructed to throw the ball at the target 5 times
xi. Subject asked what they think about when throwing the ball
b. Testing
i. Subject warm up
ii. Subject asked confidence score
iii. Subject read verbal cue 1
iv. Subject instructed to throw the ball at the target 5 times
v. Subject 2-minute rest period
vi. Subject asked confidence score
vii. Subject read verbal cue 2

23

viii. Subject instructed to throw the ball at the target 5 times
ix. Subject 2-minute rest period
x. Subject asked confidence score
xi. Subject read verbal cue 3
xii. Subject instructed to throw the ball at the target 5 times
c. Retention
i. Subject warm up
ii. Subject asked confidence score
iii. Subject instructed to throw the ball at the target 5 times
iv. Subject 2-minute rest period
v. Subject asked confidence score
vi. Subject instructed to throw the ball at the target 5 times
vii. Subject 2-minute rest period
viii. Subject asked confidence score
ix. Subject instructed to throw the ball at the target 5 times
This is a study designed to guide novice overhand throwers through the selfexploration process and explore the best means of guidance in this motor skill. The protocol
was completed in the research laboratory in of Koehler Fieldhouse at East Stroudsburg
University of Pennsylvania. The subjects reported to the laboratory for testing 3 times each.
Before testing could begin each subject was explained the possible risks and benefits of
testing for the study. Each subject was asked to carefully read and complete a Par-Q and
written consent forms. The subjects were thoroughly informed that participation in the
study was voluntary and they could drop out whenever they pleased. The subjects were
then familiarized with the protocol and asked to complete the pretest. Following the pretest, the subjects were asked to schedule their next testing appointment. Subjects were then
placed into 1 of 3 groups depending on the scores they received, 30 being the highest
possible score. The subjects were carefully distributed into groups to equally distribute the
subjects with high and low scores. The subjects were unaware of the group to which they
were assigned. Then the subjects would report for the third day of testing which would
serve as the retention test.

24

Pre-Test
Subjects were provided and signed a waiver of consent and explained that they
could drop out of the study at any time. Subjects were also provided with a PAR-Q & You
sheet (Appendix 1) that was completed and signed by all subjects. Subjects were given
time to warm up and were asked a confidence score for the 5 times they would throw the
ball in each of the 3 sets. Subjects were provided with a tennis ball once they have
familiarized themselves and warmed up. The subjects were instructed to throw the ball at
the target and hit the center of the 6 quadrants. No coaching or cueing was used during the
pre-test. The subject must wait to throw the next pitch until the researcher gives them
permission to do so. Subjects were instructed to take a 2-minute rest period after they had
thrown 5 pitches and were informed when to begin again. After the pre-test session,
subjects were asked what they were thinking about or focusing on during the throwing
trials.
Testing
Subjects were given time to warm up and were asked a confidence score for the 5
times they would throw the ball in that set and were asked again before the next 2 sets. The
target was placed 20 feet away from a marked point on the floor that the subject placed
their rear foot on. Subjects were provided with a tennis ball once they have familiarized
themselves and warmed up. The subjects were instructed to throw the ball at the target and
hit the center of the 6 quadrants. The subject must wait to throw the next pitch until the
researcher gives them permission to do so. Prior to throwing the first 5 pitches the subjects
were shown a video of an overhand thrower or given verbal cues. They would be provided
this information again during the 2-minute rest periods after the 5 and 10 pitches. No
th

25

th

researcher feedback will be given to subjects during or after testing. Only knowledge of
results will be provided by the subject themselves by whether or not they strike the center
of the target. Subjects were told to refrain from practicing any throwing in the days before
the third testing session.
Verbal Cues Used
1. Pre-first 5 pitches – “Use your body like a whip”
2. Post-first 5 pitches – “Use the ball to touch the target”
3. Post-last 5 pitches – “Shift your weight forward, pulling the ball forward”
Retention
Three days after the testing period, subjects were given time to warm up and were
asked a confidence score for the 5 times they would throw the ball and again before the
next 2 sets. Subjects were provided with a tennis ball once they have familiarized
themselves and warmed up. The subjects were instructed to throw the ball at the target and
hit the center of the 6 quadrants. No coaching or cueing was used during the retention test.
The subject must wait to throw the next pitch until the researcher gives them permission to
do so. Subjects were instructed to take a 2-minute rest period after they had thrown 5
pitches and were informed when to begin again.

26

Data Collection
All throwing blocks were recorded for each subject.
Figure 2. Subject joint angle measurement

Figure 2 shows the measurement of subject joint angle using
Dartfish software. Starting from the olecranon process, the angle was
measured by placing markers at the acromion and between the distal ends
of the radius and ulna.
Data & Measures
The data collected in the research laboratory was analyzed by a 1-way ANOVA
using the SPSS 24.0 (IBM Corporation) software. Subjects were recorded by 2 video
cameras that uploaded images to the Dartfish software that was able to analyze kinematic
data. One camera was placed posteriorly to the subject to capture the lower extremities and
to record the location of the ball when it struck the target. The second camera was placed
to the side of the throwing arm to capture the open stance of the subject in order to record

27

the internal and external rotation of the glenohumeral joint. The velocity of the tennis ball
was recorded using a pitching radar gun in miles per hour. The scores of subject throwing
sessions was calculated by a 6-quadrant pitching target that included a target in the very
center of the 6 quadrants. If a subject hit the very center of the target they would receive 2
points. If a subject hit inside any of the quadrants they would receive one point. If the
subject missed the quadrants they would receive no points. The confidence or self-efficacy
score was asked before each set of 5 throws, allotting to a total of 9 sessions of 5 throws.
The subject was asked how many time they felt that they would hit the target out of the 5
throws. Zero being the least confident and five being the most confident.
Data Analysis
SPSS 24.0 (IBM Corporation)
Instrumentation
Dartfish system – two cameras
Radar gun
Pitching target
Confidence score questionnaire
Measures
Accuracy – Pitching target: yes/no
Velocity – Radar gun: Average velocity across 15 pitches each session
Kinematics – Dartfish System: Internal, external shoulder rotation, stride length
Confidence Score – Questionnaire: Scale of 0-5 confidence of hitting the target out of the
5 throws per set
Protocols

28

A normal collegiate pitching mound is 60 feet and 6 inches away from home plate
and a little league mound is 46 feet from home plate. In order ensure that the subjects will
hit the target at a 50 percent success rate, the distance that subject stands away from the
target is 20 feet, increasing the perceived affordances of the motor task at hand. This
shortened distance is used to ensure quality data, to keep subjects interested in learning,
to avoid overuse injury, drop out and is also due to laboratory constraints. Stride length of
the pitches will be measured through video analysis via 5 markings on the floor spaced 1
foot apart. The markings were not to be used as visual cuing or learning objectives.

29

Chapter IV
Results
The purpose of this study was to compare the kinematic outcomes of using visual
and verbal cueing to educate novice performers to overhand throw and create a consistent
pattern of accuracy as well as increasing the ball velocity. Performance was evaluated in
the terms of accuracy, kinematic changes, and ball velocity. This chapter will present the
statistical analysis for changes in velocity, joint angle, and accuracy changes across pre,
mid, and post (retention test) sessions between visual, verbal and control groups.
In the pairwise comparison of the velocity factor revealed that the 2.75 increase
between pre-testing and mid testing were approaching statistical significance with a pvalue of .086. The change from pre-testing to retention which was 2.06 was not
statistically significant with a p-value of .237. There were no statistically significant
differences for joint angle, scores and no main effect for time.
Although there was no statistical significance the control group shows on average
that there is a linear trend of becoming more accurate in terms of score. The verbal group

30

shows a decrease in score during pre to mid and mid to retention, though the verbal group
started at a higher point than the other two groups. The visual group does become more
accurate in terms of score from mid-testing to retention test but because of the variation
none of these differences are statistically significant. Although remaining insignificant, as
confidence score would rise accuracy would increase as well. As these two factors would
increase the velocity of the ball would decrease. The opposite effect would occur if
velocity increased. Accuracy and confidence would decrease the ball velocity increased.

Table 1. Averages of measures

Table 1 shows the means of group measures. Velocity, Joint angle, Score, and
Confidence score.
Table 2. Means & changes of score

Table 2 shows the changes of overall score and day to day between groups.

31

Table 3. Means and changes of velocity

Table 3 shows the changes of overall velocity and day to day between groups.
Table 4. Means and changes of joint angle

Table 4 shows the changes of overall joint angle and day to day between groups.
Table 5. Means and changes of confidence score

Table 5 shows the changes of overall joint angle and day to day between groups.

32

Figure 3. Averages of scores between groups

Figure 3 shows the averages of scores between the Control (group 1), Verbal
(group 2), and Visual (group 3). The Verbal group began as the highest scoring group and
dropped to the lowest scoring group after retention testing.

33

Figure 4. Averages of velocity between groups

Figure 4 shows the averages of velocities between the Control (group 1), Verbal
(group 2), and Visual (group 3). All groups show an increase in average velocity from
pre-test to retention test.

34

Figure 5. Averages of joint angle between groups

Figure 5 shows the averages of joint angle between the Control (group 1), Verbal
(group 2), and Visual (group 3). The Verbal and Visual group showed an increase in joint
angle from pre-test to retention test but, the Control group remained almost unchanged
through 3 testing sessions. The Control group showed the most consistent increase in
average score and maintained the highest average velocity.

35

Figure 6. Changes of average confidence score between groups

Verbal
Control
Visual

Figure 6 shows the changes of average confidence score between Control (blue),
Visual (green), and Verbal (red) groups. There is no statistically significant difference
between the groups. The visual group showed the most consistent and highest increase of
confidence while the verbal began with the highest confidence, it became the group with
the lowest confidence after retention.

36

Chapter V
Discussion
The purpose of this study was to investigate and compare the kinematic outcomes
of using visual and verbal external cueing to educate novice performers to overhand
throw and create a consistent pattern of accuracy as well as increasing the ball velocity in
both acute and retention performance.
The cues that were given were in the form of verbal analogies and a video of a
professional pitcher in slow motion. Subjects were asked how many times they felt they
would place the ball inside the 6-quadrant target prior to throwing and were asked to hit
the center of 6 quadrants. The number they chose (0-5) would be their confidence score
for that set of 5 pitches. Following the 3 sets of 5 pitches the subjects were separated into
groups by accuracy scoring outcome. The confidence score that subjects gave for each set
cannot be used to objectively compare with accuracy scores. Most subjects were not very
confident on a scale of 0-5 but all subjects believed that they could successfully strike the
target with the ball at least once in 5 throws.

37

There were no statistically significant differences in accuracy, velocity or joint
angle in visual, verbal or control groups. The control group did show an increase in
accuracy score that continued through all 3 sessions. It can be said that the increase
occurred due to simply more experience throwing from the testing sessions. Due to the
fact that the subjects are novices there is not much room for a subject to decrease in
success. It can also be said that they were simply able to focus more on hitting the target
with no verbal or visual cues possibly causing perturbations.
There were only 3 subjects that had changed somewhat significantly in any factor
that was observed. 2 subjects increased accuracy scores by 8 and 9 points from pre-test to
retention and both subjects were included in the visual group. The subject with the most
dramatic decrease in accuracy score was in the verbal group and dropped by 6 points
from pre-test to retention. The verbal group was shown to have started with the highest
scores and dropped the most significantly and finished with an average score lower than
the visual and control group. Perhaps the verbal analogies were causing more
perturbation to the perceptual motor workspace or perception action coupling and caused
the subjects to interpret the cues internally and more explicitly rather than externally.
Although the visual group showed the greatest increase of average score, with 4
subjects having an increase of greater than 40% from mid-test to retention test. These
increases were not truly significant. A subject from the Visual group had a pre-test score
of 3 and had a retention test score of 12, being a 300% percent increase. Other subjects
from this group had a pre-test score of 5 and 2. The subject with a pre-test score of 2
ended with a retention test score of 10, being 400% increase. The subject that began with
a pre-test score of 5 had a mid-test score of 1 and a retention test score of 2. The increase

38

of 1 to 2 is a 100% increase. The visual group began with such low scores and had such
high percentage increases from mid-test to retention test causing figure 3 to show the
Visual group as the greatest increase of score. This group began with lower scores than
the other 2 groups, therefore the slightest increase of score would show as a drastic
increase with graphed.
Figure 7. Averages of velocity, joint angle, and score with individual groups

Figure 7 shows the averages of velocity, joint angle, and scores with individual groups to
represent the changes within each group and in comparison, to the other groups
throughout the 3 testing sessions.

39

While some results could be found as significant to an individual standpoint, there
were no significant differences found in all of the 3 groups. Certain limitations, such as
location and individual subject factors, must be taken into consideration when dissecting
this study. This study was performed indoors in a laboratory and regulation baseballs
could not be used due to laboratory constraints. This renders the results relatively useless
in regard to actual baseball pitching performance mostly due to the different consistency
and weights of a baseball compared to a tennis ball as well as distance from “mound” to
target.
Other factors of limitation include the focus of the individual subject with the
motor task at hand, stress levels, age, previous experiences and the amount of sleep that
the subject had following the motor tasks. Studies have shown that motor learning can be
enhanced by NREM sleep. This has been shown in humans as well as rodents with odorreward association tasks. Together, these findings support the hypothesis that learningrelated activity before sleep can selectively modulate the brain activity involved in sleep
spindle generation. It has been demonstrated that spindle-related spike discharges can
induce long- term potentiation in neocortical cells. Based on our findings, sleep spindles
would be the ideal physiological mechanism to facilitate the neuronal plasticity related to
motor memory consolidation processes per se (Morin, A., 2008). Although much more
research is needed to strengthen this hypothesis.
There was no statistically significant difference between control, visual
and verbal cueing groups in velocity, accuracy, and kinematics. It is important to
remember that learning involves success and failures. If learning is to occur, one must
learn from the failures and adapt to create success. If a learner succeeds less than 50

40

percent of the time they will not be as involved or focused in the activity in which they
are participating in because it becomes frustrating. If a subject succeeds at every attempt
they will not learn to adapt to different situations. When teaching movements to novices
there must be a balance of success and failure for the learner to remain involved and
enjoy what they are doing. This is something that must be understood by the person
teaching the movements or their efforts may be redundant. When teaches novices, the
attempts that end in failure are as important as the attempts that end in success.

41

Appendix I

42

APPENDIX II

43

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