Movement science and its relevance to physical therapy.

Movement Science and Its Relevance to Physical Therapy The purpose for a special series of articles in Physical Therapy devoted to movement science is threefold. First, physical therapists will be exposed to current research in this broad behavioral domain. This may have important implications for the discipline and profession of physical therapy. Second, physical therapists will have access to a body of knowledge that may have been overlooked because it was not seen as immediately relevant to clinical practice. Third, the series could serve as a basis for curriculum development and study in physical therapy education programs. By providing this exposure in Physical Therapy, unjustified barriers to particular research questions, methodologies, and related literatures may be overcome.

Two concepts are presented that provide a framework for the 23 contributions to the movement science special series. The first deals with the diversity of topics within the scope of movement science, and the second deals with the need for interdisciplinary interactions. The first concept, diversity of topics, is revealed from an examination of the contents. There are topics such as the use of animal models to provide insights into motor development (see article by Bradley in this issue) and the importance of psychosocial factors with respect to motivation governing involvement in physical activity (see article by Lewthwaite in this issue). These topics span a broad spectrum and seem to be only casually related and perhaps disconnected. A careful look at the fundamental questions raised by these and the other contributing authors reveals an important commonality among the topics. The common ground shared by our contributors is that their work is motivated by the desire to understand the nature of human movement behavior. This commonality may be seen as the major theme of the special series.

How does the scope of movement science relate to the contents of this special series? There is no single discipline of movement science per se. Instead, scientists from multiple disciplines have converged to piece together theoretical perspectives and methodologies necessary to deal with such multifaceted and complex questions as how an organism coordinates a multiple-degree-of-freedom system to produce functional movements or how practice repetitions affect the learning and retention of skilled actions. The amalgamation of diverse viewpoints is clearly evident by noting the academic departments in which our contributors hold appointments. These include human kinetics, human movement studies, kinesiology, neurology, neurophysiology, physical education, physical therapy, and rehabilitation medicine. The fields represented in the special series most certainly do not comprise all of the relevant movement science subdisciplines. The subdisciplines of exercise, physiology, and biomechanics, for example, are not formally represented.

You might ask, "What then is movement science?" The origin of the phrase is unknown; however, terms such as "human movement studies" have been used at least since the early 1970s, primarily by those in physical education, to delineate a field of study. [1] Recently, some individuals [2] have declared that movement science should be the foundation for physical therapy, particularly for rehabilitation.

Movement science, or "biological movement," was the underlying theme of a recent scientific conference held in Collingwood, Ontario, Canada. In describing the mixture of participants and speakers, Meijer and Whiting [3] captured the dilemma of defining movement science:

Drawing the lines between levels of analysis, it could be said that those arriving in Collingwood came mainly from Psychology (behavior), Physiology (mechanisms), and Physics (constraints), but recent years have witnessed a complete blurring of such level-restricted boundaries. Robotics, for example, would not fit into such a classification ... indeed, the very emergence of neuroscience reveals a tendency to cluster around fields of study rather than levels of analysis. Such, apparently, is the case with the Science of Movement. [7](p163)

Movement science is clearly a multi-disciplinary field of study. This was the prevailing sentiment in Collingwood and is reflected in the contents of this special series. Without a doubt, parent disciplines of biology, computer science, physics, physiology, and psychology contribute to the science of human movement. The particular field from which each contributor to this special series comes is, in most cases, apparent. Even more apparent is that each article is exemplary of the science of movement. Beyond discipline boundaries, the invited articles fall into three general areas of movement science research. These are concerned primarily with development, control, or learning. This December issue, which has the largest number of articles, contains contributions from all these major areas to set the stage for the articles that follow in subsequent issues. Those special series articles in the January 1991 issue will be concerned primarily with disorders of movement control, whereas those in the February issue will be devoted to issues in motor learning. The special series articles in the March issue will focus on developmental and pediatric concerns.

The diverse perspectives represented in the special series reflect a particular subset of work, primarily within the behavioral areas of movement science. The authors have attempted to provide a theoretical foundation for their work and to relate this perspective to the concerns of physical therapy. Recently, Tammivaara and Shepard [4] stated that theory in physical therapy research is all too often missing. Such theories would provide explanations for why certain practices are most effective rather than how one should perform those practices. Moreover, certain research areas, although relatively unknown to the physical therapy community, were thought by the guest editors to have important theoretical and practical implications to the developing knowledge base of physical therapy.

Nearly 50% of our contributors, though not themselves physical therapists, have interacted with physical therapy professionals as mentors, colleagues, or research collaborators. The overwhelmingly positive response from these people to contribute to the flagship journal of our profession is one indication that these scientific interactions have been perceived favorably, with perhaps mutually beneficial effects.

The second point focuses on the need for enhancement rather than restriction of scientific interactions for professional growth. Kroll captured the essence of this issue with regard to developing disciplines:

Concern that a discipline cannot be born unless it can possess a unique body of knowledge is not a critical issue.... Overlapping of disciplines reflects only the multiple efforts required in the pursuit of knowledge and disciplines have long functioned in symbiotic harmony. Territorial rights are less important than territorial development. [5](p109)

In inviting our colleagues from related disciplines to contribute, this special series of articles on movement science in physical therapy represents a move to the recognition that we are one among many scientific communities dedicated to understanding the nature of movement and its disorders. This is not to imply redundancy. Indeed, the way in which research questions among the different scientific communities are posed differs considerably. For example, the experimental psychologist asks, "What is the role of feedback in motor learning?" This entails comprehension of the relation between feedback and motor learning. Although this comprehension is of direct importance to physical therapy, the physical therapist who seeks to use feedback to control or manipulate motor learning for the benefit of the patient asks a different question. This might be, "How can feedback be used to enhance motor learning?" Each is concerned with issues fundamental to feedback and motor performance, but the ultimate aim for gaining that knowledge differs considerably.

Fifteen years ago, Hislop [6] declared that physical therapy was a profession in search of an identity. Over the years, as we attempted to define the boundaries of our profession, it appeared that we either consciously or unconsciously adopted a rather insular approach. Only 5 years ago, Mulder, [7] an experimental psychologist in the Netherlands and a contributor to this special series, bemoaned the communication gap between the physical therapist and the movement psychologist. In Mulder's view, the movement psychologist, through laboratory experimentation, is concerned with determining the fundamental principles governing motor control; the movement clinician (eg, physical therapist) is concerned with the development of treatment approaches to restore motor control. He argued that communication between those in the laboratory and those in the clinic would be mutually beneficial. For example, an understanding of the motor control deficits associated with specific neuropathologies can contribute to the development of basic principles of motor control (see, for example, articles by Corcos and by Stelmach and Phillips in the January issue). Conversely, theoretical concepts such as those associated with feedback, generalized motor programs, and functional synergies may have implications for the development of treatment procedures for the retraining of motor control (see, for example, articles by Scholz in this issue and by Mulder and Winstein in the February issue). In retrospect, the communication gap seemed to have been a necessary and important part of our growth. As our profession and discipline mature, it has become time to foster dialogue with our colleagues in related fields and to recognize areas of mutual interest.

Movement Science and Its

Relation to the Profession

and Discipline of Physical

Therapy

The importance of knowledge from the related field of movement science to the profession and discipline of physical therapy is clearly related in the profession's obligation to keep abreast of scientific advances pertinent to its practice. In particular, a profession has an inherent responsibility to improve and expand the scope of its services to society. This often involves the incorporation of new knowledge obtained from related disciplines. The knowledge obtained from related disciplines is often not directly or obviously translatable into practice. The profession thus may assume a research role to obtain the directly relevant knowledge for development of its practices. If the profession chooses to produce new knowledge itself, an interesting shift in orientation ensues. That shift implies a role change from profession to discipline. The line between profession and discipline may become blurred. While the development of new knowledge that affects practice is considered a necessary service to society that earmarks a profession, the acquisition of knowledge for fundamental understanding (ie, to advance science) characterizes the orientation of scholar-researchers within an academic discipline.

Henry defined an academic discipline as

an organized body of knowledge collectively embraced in a formal course of learning. The acquisition of such knowledge is assumed to be an adequate and worthy objective as such, without any demonstration or requirement for practical application. [8]

Movement science can be viewed as an academic discipline in the sense of Henry's definition. The acquisition of the knowledge in the academic discipline of physical therapy is assumed to be a requirement necessary for application of its professional practices and for the improvement of its professional services.

Over the last 10 years, the physical therapy profession has developed an academic discipline that is considered in some colleges and universities worthy of postprofessional graduate training and graduate degrees that are considered scholarly in orientation. In 1975, in her Mary McMillan Lecture, Hislop [6] authored the seminal concept implicating pathokinesiology as the "distinguishing clinical science of physical therapy." Hislop argued that pathokinesiology (ie, the study of movement dysfunction) embodied the fundamental and unique concepts of the "discipline" of physical therapy. Ten years after Hislop's proposal, academicians and clinicians debated the advantages and disadvantages of adopting "movement dysfunction" as the academic domain of the physical therapy profession. [9-15] It seems clear that the debate continues. Despite definitional disputes related to the collective scope of a physical therapy discipline, however, postprofessional academic programs have been developed throughout the United States, Canada, and Australia. In some cases, scholarly degrees related to the physical therapy discipline are offered in exercise science and physical education, rehabilitation science, and most recently movement science. These programs can be easily characterized as contributing to and drawing upon the broader domain of movement science.

It can be argued that the scientific foundation of our clinical practice can be supported by the emerging and broader science of movement. Carr et al's recent textbook entitled Movement Science: Foundations for Physical Therapy in Rehabilitation [2] argues for the potential usefulness to physical therapy of the research emerging from movement science. More importantly, and beyond its impact on physical therapy, there is the potential to contribute to the knowledge base of movement science. This potential for a mutually beneficial relationship has only recently been recognized by scientists working with clinicians. [7] The relationship between physical therapy and movement science must be cultivated slowly, with vision and care.

The partnership of physical therapy and movement science should be guided with objectives to develop both the practice and the science of physical therapy. This is clearly a gradual process, but one that will ultimately lead to more refined and superior practices, based upon appropriate theoretical underpinnings that are needed for any developing science. [4]

Is Immediate Application

Necessary for Relevance?

A narrow view holds that any research that is not done in a clinical setting, with patients as subjects, is useless to the practice of physical therapy. This view is perhaps more prevalent in our profession than we suspect. Is movement science research relevant to physical therapy only if it has an obvious, direct, and immediate application to clinical practice? If physical therapists view themselves as technicians or craftspersons who allow someone else to tell them that "this technique works best for this disability," [16] then nonclinically based research in movement science is definitely useless to physical therapy.

Physical therapy, however, is not a craft; it is a profession and a discipline. With this recognition comes the inherent responsibility to integrate knowledge from related research into clinical practice. All physical therapists should be proficient consumers of knowledge. This requirement entails the capability to evaluate and apply new information to professional practices. [17] Integration and application of new knowledge may not be straight-forward, particularly if the knowledge comes from nonclinical research. It is the physical therapist, however, who is best suited to take research, refine it to allow proper integration, and apply it, if appropriate, to clinical practice. Much of the research presented in this series of articles on movement science will provide an opportunity for this process and potential for important new growth.

A recent 4-year citation analysis of Physical Therapy [18] claimed that during the period from June 1980 through May 1984 there were 67 different journals cited 10 or more times. Of these, nearly 50% of the citations were from only 6 different journals. Nearly 20% of the citations were from Physical Therapy alone. Surprisingly, movement science journals such as the Journal of Motor Behavior, the Journal of Human Movement Studies, Human Learning, and the Journal of Sport and Exercise Psychology were not among those cited 10 or more times. Probably, the cited journals were appropriate, given the subject matter of the articles that referenced this literature. It could be argued that the topics of these articles constituted only a portion of the relevant knowledge base. Perhaps most disturbing was the suggestion that this list of 67 journals may represent the journals "most relevant" to physical therapy. As the physical therapy community becomes more aware of the various facets of movement science through efforts such as this special series, we will begin to see more integration of these highly relevant literatures into our practices, our research, our libraries, and our education programs.

In this introduction, we argue that interaction between movement science and physical therapy could be mutually beneficial. In the series of articles that follow, physical therapists are exposed to the diversity and scope of movement science research. Many of the articles present concepts, theoretical perspectives, research methodologies, and terminology that may be unfamiliar, yet the challenge presented by these perspectives allows for both scientific and practical advances in physical therapy.

References

[1] Brooke JD, Whiting HTA, eds. Human Movement: A Field of Study. London, England: Henry Kimpton Publishers; 1973.

[2] Carr JH, Shepherd RA, Gordon J, et al, eds. Movement Science: Foundations for Physical Therapy in Rehabilitation. Rockville, Md: Aspen Publishers Inc; 1987.

[3] Meijer O, Whiting HTA. Report of the 1988 Motor Neuroscience Symposium, Collingwood, Ontario, Canada. Journal of Motor Behavior. 1989; 21:163-175.

[4] Tammivaara J, Shepard KF. Theory: the guide to clinical practice and research. Phys Ther. 1990; 70:578-582.

[5] Kroll WP. Perspectives in Physical Education. New York, NY: Academic Press Inc; 1971:109.

[6] Hislop HJ. Tenth Mary McMillan Lecture: the not-so-impossible dream. Phys Ther. 1975; 1069-1080.

[7] Mulder T. The Learning of Motor Control Following Brain Damage: Experimental and Clinical Studies. Berwyn, Pa: Swets North America; 1985.

[8] Henry FM. Physical education: an academic discipline. Journal of Health, Physical Education, and Recreation. 1964; 35:32-33.

[9] Rothstein JM. Pathokinesiology: a name for our times? Phys Ther. 1986; 66:364-365.

[10] Schlegel R. Is pathokinesiology synonymous with physical therapy? Phys Ther. 1986; 66:366-367.

[11] Zadai CC. Pathokinesiology: the clinical implications from a cardiopulmonary perspective. Phys Ther. 1986; 66:368-371.

[12] Purtilo RB. Definitional issues in pathokinesiology: a retrospective and look ahead. Phys Ther. 1986; 66:372-374.

[13] Smidt GL. Walking the trail of physical therapy research. Phys Ther. 1986; 66:375-378.

[14] Rose SJ. Description and classification: the cornerstones of pathokinesiological research. Phys Ther. 1986; 66:379-381.

[15] Walker JM. Research in pathokinesiology: what, why, and how. Phys Ther. 1986; 66:382-386.

[16] Cubelli MG. Bridging the research gap. Clinical Management in Physical Therapy. 1989; 9(3):7. Letters.

[17] Rothstein JM. Letters: Rothstein responds. Clinical Management in Physical Therapy. 1989; 9(4):7. Letters.

[18] Bohannon RW, Gibson DF. Citation analysis of Physical Therapy: a special communication. Phys Ther. 1986; 66:540-541.

CJ Winstein, PT, PhD, is Assistant Professor, Department of Physical Therapy, University of Southern California, 2025 Zonal Ave, CSA 208, Los Angeles, CA 90033 (USA).

HG Knecht, PT, EdD, is Director of Research, Orthosport Inc, 7736 W Madison St, Forest Park, IL 60130.