Internal Visual Imagery and Its Effect on Penalty Kicks in Soccer

Transcription

1 Internal Visual Imagery and Its Effect on Penalty Kicks in Soccer BY Lindsey Gwen Sosovec A thesis submitted in partial fulfillment of the requirements for the Master of Science Major in Health, Physical Education, and Recreation South Dakota State University 2004

2 UMI Number: UMI Microform Copyright 2003 by ProQuest Information and Learning Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. ProQuest Information and Learning Company 300 North Zeeb Road PO Box 1346 Ann Arbor, MI

3 ii Internal Visual Imagery and Its Effect on Penalty Kicks in Soccer This thesis is approved as a creditable and independent investigation by a candidate for the Master of Science degree in Sport Pedagogy and is acceptable for meeting the thesis requirements for this degree. Acceptance of this thesis does not imply that the conclusions reached by the candidate are necessarily the conclusions of the major department. Jeffrey Janot, Ph.D. Thesis Advisor 4/8/04 Fred Oien, Ed.D. Head, HPER 4/8/04

4 iii Acknowledgements Special thanks to my advisor, Dr. Jeffrey Janot, for his invaluable guidance, assistance, and patience in the preparation of my thesis. Most of all I thank Dr. Janot for his assistance in the statistical analysis. I also extend special thanks to Dr. Dan Freigang for lending his soccer specific psychology knowledge and for fueling my curiosity about cognitive theory in sport. My sincere appreciation goes to Coach Lang Wedemeyer and Coach Gretchen Grenz for providing advice, support, and leadership on both the personal and professional level. I would also like to thank the women s soccer team for taking their time to volunteer as subjects and for making this study possible. Finally, appreciation is extended to the other graduate assistants for their suggestions, encouragement, and friendship throughout the last two years.

5 iv Abstract Internal Visual Imagery and Its Effect on Penalty Kicks in Soccer Lindsey Gwen Sosovec April 8, 2004 The purpose of this study was to examine the practice of internal visual imagery and explore various theories that suggest imagery, along with physical practice, can enhance performance in shooting a penalty kick in soccer. The study examined whether or not internal visual imagery, internal visual imagery plus physical practice, physical practice, or no condition improved performance on the penalty kick in soccer. In addition this study was designed to determine whether or not, in certain situations such as penalty kick shootouts, a player with effective visualization training will be at an advantage. The participants were 32 varsity level college soccer players between the ages of 18 and 22. Participants were recruited by a convenience sample through personal contact with individuals from the South Dakota State University Women s Soccer Program and college level soccer players attending the United States Soccer Federation coaching course in Tampa, Florida. The randomization procedure was as follows: Participants were numbered as a one, two, three, or four based on the order in which they arrived to complete the task. The conditions were also numbered and participants were placed accordingly. Standard descriptive statistics (means, standard deviation, range) were used to present subject demographics, accuracy of the kicking task for both directions, and clarity

6 v of imagery. A t-test was used to analyze the difference in clarity of images between the imagery and imagery plus practice conditions. In addition, a one-way Analysis of Variance (ANOVA) procedure was completed to determine overall group differences on task accuracy for both kicking directions. Results showed that the imagery plus practice condition had significantly (p <.05) greater clarity of images when compared to the imagery condition. Shooting accuracy to the left direction had a significant difference (p <.05) between means for the imagery plus practice and control conditions. Shooting accuracy to the right direction had no significant difference (p >.05) between any of the conditions. Only the control group and the imagery plus practice group differed significantly. The performance of the imagery and imagery plus practice group is inconsistent with current literature. These results suggest that internal imagery may not always be the optimal perspective for performance enhancement on the penalty kick in soccer. In the present study, the imagery training exposed the subjects to the psychological dimension of the game but the quality, quantity and realism of the exposure limited the success of the participants. Although the imagery conditions did not result in definite improvement of the penalty kick, it enhanced the participants overall knowledge of the components of soccer.

7 vi Table of Contents Page Signature Page Acknowledgements Abstract.. List of abbreviations.. List of tables.. List of figures ii iii iv ix x xi Chapter 1. Review of Literature.. 1 The first discussions of imagery 1 The experimental science of imagery 2 Details of mental imagery. 3 The connection between imagery and motor performance 3 Theories and thought explaining the use of mental imagery for motor performance. 4 Imagery rehearsal and its effects in a variety of tasks 6 Imagery rehearsal and its effects in soccer. 12 Interference effects of mental imagery on a motor task Introduction

8 vii Problem 18 Purpose Methods and Procedures.. 20 Study Participants Procedures Manipulation Check Statistical Analysis Results Image Clarity for imagery versus imagery plus practice.. 25 Penalty kick accuracy for all conditions: right and left directions 25 The analysis of overall penalty kick accuracy Discussion References. 32 Appendix A Procedures checklist for testing 43 Appendix B General information sheet Appendix C Information sheet for participants 49 Appendix D Imagery testing form 52 Appendix E Imagery plus practice testing form.. 54 Appendix F Practice testing form 56 Appendix G Control testing form. 58

9 Appendix H Consent form. 62 viii

10 ix List of Abbreviations (VMBR) - Visual Motor Behavior Rehearsal (ISM) - Triple Code Model of Imagery (ANS) - Autonomic Nervous System (PK) Penalty Kick (NCAA) National College Athletic Association (SDSU) South Dakota State University (CSAI-2D) - Competitive State Anxiety Inventory (A-DES) - Adolescent Dissociative Experience Scale (CPKT) - Crossman Penalty Kick Test

11 x List of Tables Page Table 1 Image clarity Table 2 Standard descriptive statistics for shooting accuracy both directions Table 3 Penalty kick accuracy.. 43

12 xi List of Figures Page Figure 1 Clarity for imagery versus imagery plus practice Figure 2 Shooting accuracy to the right direction for each condition. 37 Figure 3 Shooting accuracy to the left direction for each condition Figure 4 Shooting accuracy for each condition by total shots made and direction

13 1 CHAPTER I Review of Literature For ease of presentation the review of literature was divided into eight subsections: (a) the first discussions of imagery, (b) the experimental science of imagery, (c) details of mental imagery, (d) the connection between imagery and motor performance, (e) theories and thought explaining the use of mental imagery for motor performance, (f) imagery rehearsal and its effects in a variety of tasks, (g) imagery rehearsal and its effects in soccer, and (h) interference effects of mental imagery on a motor task. The First Discussions of Imagery The classical Greek philosophers set the stage for subsequent discussions of imagery. Plato speaks (metaphorically) of an inner artist painting pictures in the soul, and suggests that memory might be analogous to a block of wax into which our perceptions and thoughts stamp impressions (Theatatus 191c,d). Aristotle endorses this wax impression model of memory, and describes this impression as a sort of picture (De Memoria 450a,b). Aristotle introduced the notion of a mental faculty of imagination, allied to perception, and responsible for producing and recalling imagery (De Anima III.iii). Aristotle was the first systematic cognitive theorist, and gave imagery a central role in cognition. He asserts that "The soul never thinks without a mental image" (De Anima 431a 15-20), and maintains that the representational power of language is derived

14 2 from imagery, spoken words being the symbols of the inner images (De Interpretatione 16a; De Anima 420b). The Experimental Science of Imagery When psychology first began to emerge as an experimental science, in the philosophy departments of the German universities in the late 19th century, the central role of imagery in mental life was not in question. Wilhelm Wundt, acclaimed "the father of experimental psychology", established the first psychological research and teaching laboratory in the Leipzig Philosophy Department around 1876 (Fancher, 1996). He regarded his psychology as a branch of philosophy, an attempt to apply the experimental method of natural science to essentially philosophical problems concerning the nature of mind and its metaphysical status. This view of the subject persisted, in Germany, at least until the Nazi era. Wundt's research program aimed to investigate the "elements of consciousness," and the laws governing the combination of these elements (Wundt, 1912). Although his theoretical system made a place for emotional feelings as one class of element, in practice the main focus of Wundt's experimentally based research program was on the elements of sensation and their compounding into ideas. As has been the case in the philosophical tradition, these ideas were conceived as mental images. Indeed, Wundt insists that there is no fundamental difference in kind between the ideas arising directly from perception and "memory images" (Wundt, 1912). Thus, Wundtian experimental psychology was largely a study of cognitive processes and the mental image.

15 3 Details of Mental Imagery Mental imagery (sometimes colloquially called visualization, or "seeing in the mind's eye") is an experience that resembles perceptual experience, but which occurs in the absence of the appropriate stimuli for the relevant perception (cf. Finke, 1989; McKellar, 1957). Very often these experiences are understood by their subjects as echoes or reconstructions of actual perceptual experiences from their past; at other times they may seem to anticipate possible, often desired or feared, future experiences. Thus imagery has often been believed to play a very large, even pivotal, role in both memory (Yates, 1966; Paivio, 1986) and motivation (McMahon, 1973). Indeed, it has usually been regarded as crucial for all thought processes, although, during the 20th century in particular, this has been called into question. The Connection Between Imagery and Motor Performance Although there has been some doubt shed on the neuromuscular (or psychoneuromuscular) theory (Feltz & Landers, 1983), it is perhaps the most obvious and direct basis for understanding the connection between imagery and motor performance. Jacobson (1930, 1931, 1932; Hale, 1982) demonstrated that action potentials recorded from specific muscles changed during recall of movements. The finding that movement imagery produces impulses to perform the movement itself is called the "Carpenter Effect" (Ulich, 1967), named after the individual who proposed the "ideo-motor principle" (Carpenter, 1894).

16 4 The Carpenter Effect is split into a multitude of modes including, human action, reaction, and expression. It appears that under specific internal and external conditions, expressions of the entire personal situation change. This effects and is reflected on a person s motor level (Carpenter, 1894). Theories and Thought Explaining the Use of Mental Imagery for Motor Performance Sports psychologists have attempted to understand the exact mechanisms that cause mental imagery to work. Numerous theories exist, but sports psychology lacks a single theory which completely explains the effectiveness of mental imagery. Carpenter proposed the earliest theory in 1894 called the psychoneuromuscular theory. This theory maintains that imagery rehearsal duplicates the actual motor pattern that is being rehearsed. His view is that the motor patterns, which are generated during imagery practice, are the same as those used for physical practice. Another prominent theory is the symbolic learning theory. This differs from the previous theory that instead of imagery working due to muscle activation, mental imagery works from the opportunity to practice the symbolic elements of a motor task. Therefore, it is assumed that the learning obtained from imagery relates to cognitive learning (Fink, 1985). A third theory, called the arousal/activation theory, connotes that by practicing imagery, one will obtain a level of arousal that is optimal for the specific performance. The arousal functions as a way of "priming" the muscles which results in a lowering of

17 5 the sensory threshold of the performer to facilitate performance (Kosslyn, 1994). Peter Lang developed an information-processing model of imagery, which presumes that an image is a functionally organized, definite set of propositions stored by the brain. It is not simply a stimulus in a person s head to which one responds. This image has two main types of statements: response propositions and stimulus propositions. The latter describes the content of the scenario to be imagined. Response propositions, on the other hand, describe the imager s response to that scenario. Lang further states that an image contains a motor program which holds instructions for the imager on how to respond to the image. Hence, the image is a template for overt responding. So modifying either overt behavior or vivid imagery will result in a change in the other (Suinn, 1990). Another popular theory is Suinn s visual motor behavior rehearsal (VMBR) model which suggests that imagery should be a holistic process that includes a compete reintegration of experience. This includes visual, auditory, tactile, emotional, and kinesthetic cues. The study demonstrated that physiological responses can result from athlete s usage of mental imagery. Suinn s method is one of the few which has solid evidence to support its effectiveness. A more recent model, which also places importance on psychophysiology, goes even farther by including a specific meaning for an image. This model is known as Ahsen s Triple Code Model of Imagery (ISM) (Murphy, 1990). According to Ahsen there are three fundamental parts to an image. The first part is that the image itself must be a centrally arousing sensation so it is more like the real world. It has all the attributes

18 6 of a sensation; the only difference is that it is internal. This image provides the imager with so much realism that it can enable him or her to interact with the image as if it were the real world. Secondly, there exists a somatic response. Therefore, the very act of imaging results in psychophysiological changes in the body. Finally, the third part of the image is the actual meaning of the image. Every image has a significant meaning and that specific meaning can imply something different to each individual. Since every person has a unique background and upbringing, the actual internal image can be quite different for each individual, even though the set of imagery instructions are the same (Murphy, 1990). Imagery Rehearsal and its Effects in a Variety of Tasks A study by Vandell, Davis, and Clugston (1943) first introduced the hypothesis that mental rehearsal is effective in developing skilled motor performance. The study attempted to determine the function of mental practice in the acquisition of dart throwing and basketball shooting skills. The results stated that a lack of definite physical practice of a motor skill resulted in no improvement in later performance of that motor skill, and that daily physical practice of a motor skill resulted in definite improvement in the performances of that motor skill. Conclusions were also made that daily mental practice of a motor skill resulted in improvement in the later physical performance of that particular motor skill to such an extent that mental practice appeared to be almost as effective as actual practice.

19 7 During the 60 s and 70 s, the studies conducted on mental imagery were rather inconsistent due to different confounds such as lack of subjects and reliable controls. In addition, researchers used a variety of skills because they were not exactly sure what the subjects should do when they engaged in mental practice. However, now there is sufficient reliable evidence that suggests imagery rehearsal can sometimes improve motor performance in a variety of sports (Paivio, 1985; Isaac, 1992; Roure, 1998; Martin, 1995; Pie, 1996; Baron, 2000; Light, 2000; Crossman, 1992). Feltz and Landers (1983) conducted a meta-analysis to examine 60 studies in which mental practice was compared to control conditions. The analysis suggested that mental imagery practice influences performance more than no practice, but is consistently less effective than physical practice. On average, the effect sizes were larger with the studies that used cognitive tasks. Overall, the cognitive rehearsal conditions showed a better performance, about one-half of a standard deviation unit (Paivio, 1985). In 1992, Isaac conducted a study which examined the influence of mental practice on sports skills. While most of the previous studies on this topic showed positive effects of mental rehearsal, the studies were not performed in actual field context using subjects who learned actual sport skills rather than just novel motor tasks (Isaac, 1992). Isaac (1992) eliminated this problem in the experiment. The hypothesis of whether people who have better images and control over their images result in better performances was tested. Isaac (1992) tested 78 subjects and classified them as novice or experienced trampolinists. The study then further divided the two groups into an experimental and

20 8 control group. The study classified the subjects as either high or low imagers based on initial skill level. Both the high imagers and low imagers were trained in three skills over a sixweek period. In order to prevent confounds, the imagery group was unknown to the experimenter until afterwards. The experimental group physically practiced the skill for 2.5 minutes, which was then followed by 5 minutes of mental practice. Lastly, an additional 2.5 minutes of physical practice followed the mental practice. Meanwhile, the control group physically worked on the skill for 2.5 minutes, which was then followed by 5 minutes of a session trying a mental task of an abstract nature, such as math problems, puzzles, and deleting vowels. Then, 2.5 more minutes were spent physically working on the skill again. The outcome of the experiment was as followed: there existed a significant difference in the improvement of the high and low imagers. Where the initial skill ability was similar, the high imagery groups showed significantly more improvement than the low imagery group. Furthermore, there was a significant difference between the experimental and control groups. Not surprisingly, the experimental group had significantly more improvement than the control group. This study suggests that despite the level of skill (beginner or experienced) visual imagery proves effective (Isaac, 1992). In a recent experiment conducted by Roure et al (1998), results found six specific autonomic nervous system (ANS) responses that correlated with mental rehearsal, thereby improving sports performance. The subjects were placed into an imagery group and a control group. The task measured in each group was based on their ability to pass

21 9 an opponent s serve to a given teammate, in the sport of volleyball. The experimenters measured the variations of the ANS during the motor skill and during the mental rehearsing sessions. The ANS parameters tested included: skin potential and resistance, skin temperature and heat clearance, instantaneous heart rate, and respiratory frequency. The results of the test revealed a strong correlation between the response in the actual physical tasks (both pre- and post-test volleyball) and during the mental imagery sessions. There existed a difference in the skills between the imagery and the control group, the former being the better. In addition, no clear difference was present between the pre- and post- tests in the control group. This study showed that mental imagery induces a specific pattern of autonomic response. These include: decreased amplitude, shorter duration and negative skin potentials when compared to the control group. As a consequence of the ANS, the imagery group was associated with better performance. In light of this experiment, Roure et al suggested that metal imagery might help in the construction of schema that can be reproduced, without thinking, in actual practice (Roure et al, 1998). Not only does mental imagery seem to enhance athletic performance, but it has been shown to enhance intrinsic motivation as well. A study in 1995 tested who would spend more time practicing a golf-putting task and who would result in having higher self-efficacy. Thirty-nine beginner golfers were grouped into an imagery or control group. For three sessions, both groups were taught how to hit golf balls. The imagery group practiced in an imagery training session designed for this specific golf skill. As a result, the imagery group spent significantly more time practicing the golf-putting task

22 10 than the control group. In addition, the subjects in the imagery group had more realistic self-expectation, set higher goals to achieve, and adhered more to their training programs outside the experimental setting (Martin & Hall, 1995). A study determining the impact of imagery on throwing balls into a basket conducted by Pie (1996), further studied the relationship of imagery to a motor skill. Two studies were used. In both studies participants used relaxation and imagery to experience and feel the movement of shooting a ball. Four basketball free throw trials were held once a week in the first study, and twice a week in the second. The results varied, suggesting that the imagery was effective only if the individual had mastered the task. The conclusions suggest that practicing imagery of a skill, which is not yet mastered by the subjects, will result in two possible outcomes. Study one indicated that physical performance may increase as a result of improving acquaintance with the task. Study two indicated that physical performance was sustained at the same level through the tasks indicating an improved acquaintance with imagery does not affect the task (Pie, 1996). Evidence from a 1986 study concludes that athletes should perhaps use different imagery perspectives depending on the type of sport or skill they are trying to enhance, and depending on their level of experience with that skill. This study found that different tasks might show differential benefits from different imagery perspectives (Finke, 1986). Additionally, a study conducted by Smith et al in 2001 determined whether imagery interventions based on bio-informational theory was more effective in enhancing

23 11 motor skill performance, namely the field hockey penalty flick, than those based solely on stimulus proposition-based scripts. These results provide strong support for the effectiveness of imagery as a means of enhancing the hockey penalty flick performance of beginners. The stimulus and response proposition-based intervention produced significantly greater improvements than the stimulus proposition-only intervention, providing clear support for the prediction of bio-informational theory. This study suggests the need to personalize imagery scripts based not only by the relative performances of the two experimental groups, but also by the responses given by the participants when interviewed following the pre-test. All the participants reported differing physiological responses when performing the hockey flick. No two answers were identical, indicating that, if sport psychologists use generic scripts rather than personalized ones, some athletes may have difficulty relating to them, and therefore the imagery is likely to be less effective (Smith, Whitemore, Collins & Davenport; 2001). Feltz and Landers conducted a meta-analysis indicating that, in general, performance on cognitive tasks shows greater improvements from visual imagery compared to performance of either motor or strength tasks (1983). Similarly, another study conducted by Hird, Landers, Thomas, and Horan (1991) found better performance with physical practice for both a motor task and a cognitive task, but a larger effect size for the cognitive (ES = 1.06) than motor (ES =.50) task.

24 12 Imagery Rehearsal and its Effects in Soccer Specific studies on the use of imagery in soccer were examined. One study assessed the potential for absorptive capacity to serve as a mediating factor in the efficacy of imagery training for youth soccer players. The study featured a quasi-experimental design incorporating two groups, pre and post-tested, and employing a time series intervention. Participants were male and female youth soccer players participating in a suburban Philadelphia travel soccer program. Participants ranged from 9 to 16 years of age. The two groups were determined randomly prior to all testing. Pre-testing included a demographic profile, assessment of non-dominant leg kick distance, and completion of the Adolescent Dissociative Experience Scale (A-DES) (Baron, 2000). The treatment consisted of participant use of three audiotaped imagery-training sessions. At the completion of each week, over a period of three weeks, a tape was returned along with a compliance card. Post-testing for all participants included a re-test of kick distance and the A-DES (Baron, 2000). The analysis began with an examination of the distributional properties of the variables. Skewed variable distributions were transformed using natural logarithms. For the complex hypotheses contrasting the effects of an imagery intervention on change in athletic performance, a repeated-measures multivariate analysis was employed. Pearson product moment correlations were employed for the simple associations (p <.05). One hypothesis was found to be statistically significant, the interaction of time with group membership were not found to mediate this effect. Age and sex were not found to correlate with absorptive capacity. As for sex differences in absorptive scores, the

25 13 variances of absorption scores between males and females failed to pass Levene's test for Equality of Variances. The results support the efficacy of imagery training for this population. Based on this study, absorption did not mediate this effect (Baron, 2000). The aim of Light s 2000 study was to determine the effects of an eight week imagery intervention based on the motivation general arousal element of Pavio's (1985) analytical framework of imagery effects in: (a) modifying perceptions of anxiety from negative to positive, and (b), improving performance of the penalty kick. Using a treatment (imagery) and no treatment (no imagery) design, two male and two female representative youth soccer teams completed a modified version of the Competitive State Anxiety Inventory (CSAI-2D) five minutes before taking five penalty kicks. Participants who reported debilitative state anxiety as indicated by the CSAI-2D were then allocated to imagery and no imagery groups. Following the eight-week intervention participants were again assessed on penalty kick performance. The imagery sessions were concluded to minimize anxiety and improve motor performance (Light, 2000). The purpose of Crossman s 1992 study was to investigate the effect of three practice methods on the learning of a soccer penalty kick. Thirty varsity level soccer players at Covenant College were tested at the beginning, midway and at the end of the practice sessions on the Crossman Penalty Kick Test (CPKT). The subjects were put into three practice groups based on their pre-test scores. Each group was subjected to a different practice treatment for eight days. The three practice methods included: (1) internal imagery, (2) slow-motion mental practice, and (3) no practice (control). The VAX 3900 system with MINITAB 7 at the Covenant College Information

26 14 Processing Center was used to analyze the data. T-tests were used to measure the mean difference in each group for: (1) mean change #1 to mean change #2, and (2) mean change #3. A t-test was also used to measure change between low and high ability groups for mean change #3. A two-way Analysis of Variance was utilized to compare mean differences between ability levels from mean change #1 and mean change #2. The results of the study showed: (1) significant differences for mean gain #3 for the internal imagery and slow-motion mental practice groups, (2) no significant differences for mean gain #3 for the control group and ability level groups, (3) significant difference from mean gain #1 to mean gain #2 for the internal imagery group, (4) no significant differences from mean gain #1 to mean gain #2 for the control and slowmotion mental practice groups, and (5) no significant difference was found between the low and high level ability groups when comparing mean gain #1 to mean gain #2. In conclusion, internal imagery and slow-motion mental practice proved to be effective in learning a soccer penalty kick. Also, mental practice was of more benefit early in the motor skill learning process (Crossman, 1992). Salamon, Hall & Haslam (1994) investigated the motivational and cognitive use of imagery by 362 national, provincial, and non-elite (local) soccer players aged years. The Imagery Use Questionnaire for Soccer Players examined when players use imagery and whether or not it is used to assist with game strategies, individual skills, motivation levels, and goal-oriented responses. Results indicated that soccer players tendrd to use imagery more in conjunction with competition than with training. The study also reported that soccer players used

27 15 imagery more for its motivation function than its cognitive function. In general, the elite athletes reported using more imagery than non-elite athletes regardless of the function imagery served (Salmon et al, 1994). Interference Effects of Mental Imagery on a Motor Task It can be argued that imagery and physical practice are functionally similar. Evidence in support of this hypothesis comes from several experiments demonstrating that interference effects from imagery in motor learning and motor memory are similar in both direction and size to those resulting from physical practice. The purpose of a 1995 study was to provide additional support for this finding using a retroactive interference paradigm. Sixty participants were required to practice performing a simple motor task. They then were randomly assigned to one of six groups. These groups differed in the amount and type of interpolated practice they experienced. One physical practice group attended one session of interpolated activity involving physical practice of another motor task. The other physical practice group participated in two such sessions. One imagery group attended a single session entailing imaginary practice of the same interpolated motor task, while the other imagery group had two such sessions. A fifth group experienced a combination of physical practice and rest periods for two interpolated sessions. A control group did not experience any interpolated activity sessions (Hall, Bernoties & Schmidt; 1995). Following the interpolated activity sessions, all groups were given a retention/reacquisition test on the original motor task. Imagery and physical practice

28 16 during the interpolated activity sessions caused similar interference effects on retention/reacquisition. All groups showed greater deviation from the criterion movement during the retention test than the control group (Hall, Bernoties, & Schmidt, 1995).

29 17 CHAPTER II Introduction Imagery is not only associated with fantasy and imagination, but also with cognitive functions such as memory, perception, and thought. Although imagery occurs in all sensory modes, most work in philosophy, psychology, and cognitive science has concentrated upon visual imagery. Visual imagery is a basic form of cognition and plays a central role in many human activities ranging from navigation, to memory, and creative problem solving (Aristotle, 1936). Mental imagery, also called visualization and mental rehearsal, is defined as experience that resembles perceptual experience, but which occurs in the absence of the appropriate stimuli for the relevant perception. Whenever a person imagines herself performing an action in the absence of physical practice, she is said to be using imagery. While most discussions of imagery focus on the visual mode, there exist other modes of experience such as auditory and kinesthetic. These are just as important; however, for the purposes of this study, only visual imagery will be discussed as it is the most relevant mode concerning athletic performance (Fancher, 1996). The positive effects of mental practice are well documented (Corbin, 1972; Richardson, 1965a, 1965b; Weinberg, 1982; Feltz & Landers, 1983; Feltz, Landers & Becker, 1988; Hinshaw, 1991), but due to variability across studies it has been difficult to determine which specific aspects of mental practice yield the greatest improvement in performance (Murphy, 1990). Based on published research, internal visual imagery

30 18 seems promising and beneficial for athletes (Paivio, 1985; Isaac, 1992; Roure et al, 1998; Martin & Hall, 1995). Although it seems to not be as beneficial as physical practice, visual imagery fairs better than no practice at all (Pie, 1996; Baron, 2000; Light, 2000; Crossman, 1992). Hence, a study designed to examine the performance of soccer players who participate in a program that combines physical practice with mental training, could be beneficial to athletes and coaches. Many studies show that mental training improves motor skills (Paivio, 1985; Isaac, 1992; Roure, 1998; Martin, 1995; Pie, 1996; Baron, 2000; Light, 2000; Crossman, 1992). More recently, some studies suggest that visual imagery can improve various skills, enhance motivation, develop mental toughness, and instill confidence; all which will help elevate a player s level of play (Martin, 1995; Light, 2000; Roure, 1998). In an extensive review of mental practice research, Murphy (1990) identified several weaknesses in the current research literature that may explain some of the inconsistencies. Experimental control was identified as a major problem and advocated the use of post-experimental questions to exclude subjects who did not or could not follow the required experimental procedures. In the past decade there has been much interest in the use of imagery to enhance sport performance. Likewise, several ways in which athletes use imagery have been identified. The purpose of this study was to examine the practice of internal visual imagery and validate assumptions that imagery, along with physical practice, can enhance performance in shooting a penalty kick in soccer.

31 19 The purpose of this study was to determine whether or not, in certain situations such as penalty kick shootouts, a player with effective visualization training will be at an advantage. This can prepare players for the pressure of the kick by creating disciplined performance routines. Thus, while preparing for their turn, they can be mentally rehearsing their technique (already mastered through training and visualization) that can help keep their confidence and remove any distractions such as crowd noise.

32 20 CHAPTER III Methods and Procedures For ease of presentation the methods and procedure will be divided into four subsections: (a) study participants, (b) procedures, (c) manipulation check, and (d) statistical analysis. Study Participants The participants were 32 skilled soccer players. The skilled soccer players were all varsity level female college soccer players. All participants were females ages The 32 volunteers who met the criteria were asked to fill out an information sheet and a consent form. The consent form was previously approved by the Human Subjects Committee at South Dakota State University. Subjects were recruited by a convenience sample through personal contact with subjects from the South Dakota State University Women s Soccer Program and college level soccer players attending the United States Soccer Federation coaching course in Tampa, Florida. This study was conducted at South Dakota State University soccer practice fields and at the University of South Florida soccer practice fields in Tampa, Florida. The study examined specifically the differences in accuracy between a control group, a physical practice only group, an internal visual imagery group, and an internal visual imagery plus physical practice group.

33 21 Procedures The penalty kick task was conducted on an outdoor soccer field to maintain high ecological validity, with the penalty kick mark being regulation distance from a regulation height and width goal. The regulation distance of the penalty kick mark is 12 yards. The regulation goal dimensions are eight foot tall by eight yards wide. A regulation, size five soccer ball was used. Two orange disc cones were placed 1.5 feet from each goalpost creating a gate on each side of the goal. The participants were initially informed about the penalty kick competition and were reminded that the aim of each shot was to place the ball through the gate between the disc cone and the goal post. After this introduction, the participants completed four practice shots, two to each side. Participants were allowed to use either foot to complete the task. The main aim of this practice was to familiarize the participants with the task and minimize any practice effects. After this practice period, the participants were randomly allocated to the group in which they would perform the imagery conditions. The randomization procedure was as follows: Participants were numbered as a one, two, three, or four based on the order in which they arrived to complete the task. The ones were the imagery group, the twos were the imagery plus physical practice group, the threes were the practice group, and the fours were the control group. The groups and imagery conditions were as follows: The imagery group was asked to abide by the following instructions: Close your eyes, now get as clear and vivid an image as possible of the ball from the point when it leaves your foot, rolling away from you along the desired line, at the

34 22 desired speed, towards the gate, and rolling right through the center of the gate and into the corner of the goal. They were asked to visualize ten shots, five to each side. The imagery plus practice group completed the above imagery. Following the imagery they took one practice shot. Again they completed the imagery and took another practice shot. There were a total of ten visualization shots and ten practice shots, five to each side. The practice group was allowed to complete ten practice shots, five to each side. The control group did not participate in practice or imagery. Following the appropriate conditions, all participants took ten penalty kicks, five to each side. Only balls that went through the gate between the disc cone and the goalpost were considered as having scored. A ball that missed the gate, hit the cone, or hit the post was considered as having not scored. Manipulation Check The trials were done with one participant at a time on the field to avoid distraction. The participant first took the four practice shots, two to each side, to familiarize themselves with the task. Following the familiarization session, the participant performed the condition in which they had been assigned. After the condition, the participant took the ten penalty kicks, five to each side and the scores were recorded. Throughout all trials, the participants were reminded after every shot that the aim of the task was to put the ball through the gate. After every imagery condition, the

35 23 participants were asked if they were managing to maintain a clear and controlled image of the appropriate outcome. When a participant indicated that they could not maintain a clear image, they were advised to take their time and concentrate on the desired outcome image. At the end of the imagery conditions, the participants were asked to indicate on a scale of 1-9 how clear the outcome images were that they imagined throughout the condition (with 1 indicating that every image was unclear and 9 indicating that every image was clear and vivid). After the completion of all conditions, the participants were also asked if they had used any additional strategies throughout the trials. For example if the control group was using positive outcome imagery under the control conditions they were to be excluded from the analysis. Statistical Analyses Standard descriptive statistics (means, standard deviation, range) were used to present subject demographics, accuracy of the kicking task for both directions, and clarity of imagery. A t-test was used to analyze the difference in clarity of images between the imagery and imagery plus practice conditions. In addition, a one-way Analysis of Variance (ANOVA) procedure was completed to determine overall group differences on task accuracy for both kicking directions. If the one-way ANOVA demonstrated overall group differences, a Tukey s HSD post-hoc test was run to determine significant pairwise differences between groups. The GraphPad Prism statistic package (GraphPad Software, Inc., San Diego, CA., version

36 24 3.0) was used to analyze the data. Alpha level was set at.05 to determine significant differences for all analyses.

37 25 CHAPTER IV Results For ease of presentation the results will be divided into three subsections: (a) Image clarity for imagery versus imagery plus practice, (b) Penalty kick accuracy for all conditions: right and left direction and (c) Overall penalty kick accuracy. Image clarity for imagery versus imagery plus practice Clarity between the imagery condition and the imagery plus practice condition are presented in Figure 1. It was found that there was a significant difference in means (p <.05) between the imagery condition and the imagery plus practice condition. This concludes that the imagery plus practice condition had significantly greater clarity of images when compared to the imagery condition. The total number of values for clarity of the imagery condition was eight. The minimum was 6.0, the maximum was 8.0 and the mean was 7.0. The total number of values for clarity of the imagery plus practice condition was also eight. The minimum was 7.0, the maximum was 9.0 and the mean was 7.9. See Table 1 for descriptive statistics. Penalty kick accuracy for all conditions: right and left direction The total numbers of shots made to the right direction (out of 40) were as follows: The imagery condition made 21 shots, 52.5%; the imagery plus practice condition made 24 shots, 60%; the practice condition made 31 shots, 77.5%; and the control group made

38 26 26 shots, 65%. The total numbers of shots made to the left direction (out of 40) were as follows: The imagery condition made 19 shots, 47.5%; the imagery plus practice condition made 18 shots, 45%; the practice condition made 28 shots, 70%; and the control group made 30 shots, 75%. Shooting accuracy to the right direction is presented in Figure 2. After completing an ANOVA there was no significant difference (p >.05) between the imagery condition and the imagery plus practice condition, the imagery condition and the practice condition, the imagery condition and the control condition, the imagery plus practice condition and the practice condition, the imagery plus practice condition and the control condition or the practice condition and the control condition. The means and standard deviations for each condition were as follows: The imagery condition had a mean of 2.6 and a standard deviation of 0.74, the imagery plus practice condition had a mean of 3.0 and a standard deviation of 1.4 the practice condition had a mean of 3.9 and a standard deviation of 0.83, and the control group had a mean of 3.3 and a standard deviation of 1.5. Shooting accuracy to the left direction is presented in Figure 3. After completing an ANOVA there was no significant difference (p >.05) between the imagery and imagery plus practice conditions, the imagery and practice conditions, the imagery and control conditions, the imagery plus practice and practice conditions, or the practice and the control conditions. However, there was a significant difference (p <.05) between means for the imagery plus practice and control conditions. The imagery condition had a mean of 2.4 and a standard deviation of 1.4, the imagery plus practice condition had a

39 27 mean of 2.3 and a standard deviation of 1.0, the practice condition had a mean of 3.5 and a standard deviation of 0.9, and the control group had a mean of 3.8 and a standard deviation of 0.7. (See Table 2). Overall penalty kick accuracy The overall penalty kick accuracy of the imagery condition was 40 shots, 50%. The imagery plus practice condition had 42 total shots made, 52.5%. The practice condition had 59 total shots made, 73.8%. The control group had 56 total shots made, 70%. Overall shooting accuracy is presented in Figure 4 and Table 3.

40 28 CHAPTER V Discussion This study determined whether or not internal visual imagery, internal visual imagery plus physical practice, physical practice, or no condition improved performance on the penalty kick in soccer. Only the control group and the imagery plus practice group differed significantly. Although the performance of the imagery and imagery plus practice group is inconsistent with the current literature, the explanations that have been proposed to explain this cannot easily account for the present results. The greater effects of internal imagery have usually been attributed to the muscle innervations occurring in the actual muscles during imagery (Hale, 1982). The penalty kick task in the present study involved very little muscle movement and the movements that did occur were trivial for the advanced level of the subjects. Evidence in this study concludes that soccer players should perhaps use different imagery techniques depending on the type of skill they are trying to enhance and depending on their level of experience with that skill. In the present study, the penalty kick task was very basic with little to no outside stimuli. The task was simplified to mimic an inside of the foot pass. In this study, the penalty kick was not performed under game-like conditions. This research suggests that imagery should be a holistic process that includes a complete reintegration of experience. This includes visual, auditory, tactile, emotional, and kinesthetic cues. If coaches cannot create a more game-like situation with stressors

41 29 such as crowd noise, pressure, and anxiety, then the penalty kick task becomes very basic and unrealistic. Also, if coaches use generic scripts rather than personalized ones, some athletes may have difficulty relating to them, and therefore the imagery is likely to be less effective. These results suggest that internal imagery may not always be the optimal perspective for performance enhancement on basic motor tasks. The present study finds some support for the symbolic learning imagery hypothesis for the early stages of learning motor tasks. In previous research, mental practice was of more benefit early in the motor skill learning process (Crossman 1992). Therefore, at this stage of learning the imagery conditions are not as beneficial. Previous theory also suggests that imagery training should include testing that identifies the participants imagery level. The imagery training should be a complex process that includes relaxation, mental training, motivation arousal, and daily practice. The limited success of the imagery of participants in the present study may have been due to the acute mental practice. The subjects mental imagery ability was not trained or measured in any way. Another interesting finding was the relationship between image clarity and penalty kick accuracy. This supports the hypothesis that people who have better images and control over their images will have better performance results (Isaac, 1992). Previous literature has indicated that soccer players tend to use imagery more in conjunction with competition than with training. This literature also reported that soccer

42 30 players use imagery more for its motivation function than its cognitive function (Salmon, 1994). A coach should create an environment for each level of player so that it challenges the player and instills a high level of excellence. The coach is an assistant to the game as a teacher, and an assistant to the players in understanding the game. The demand and realism of the imagery should replicate the game so that players, on game day, are not asked to execute the skills of the game that they have not experienced in imagery training. According to the United States Soccer Federation, one of the four components of coaching soccer is psychology. The priority of this component differs depending on the age and ability of the players. Therefore, a coach should be aware of the impact that psychology plays in the development of soccer players. Coaches should create an environment that supports cognitive and psychosocial development, as well as physical and motor skill development. According to the National Soccer Coaches Association of America, soccer is the player s game and the paramount concern of coaches is the holistic development, welfare, enjoyment, and safety of the players. Coaches bear the responsibility for teaching players to strive for success, and to present the players with the tools necessary to be successful. Players are generally exposed to all dimensions of the game during a training session. This includes tactical, technical, physical and psychological components. However, the quality and quantity of this exposure will directly affect personal performance levels. In the present study, the imagery training exposed the subjects to the