The rebound accuracy of tennis impacts was studied by measuring the vertical angles of approach and rebound of tennis balls projected in a vertical plane at a clamped racket. Three identical oversized tennis rackets were strung with nylon at 200, 267, and 334 N of tension. Ten impacts were filmed at 200 Hz for each string tension with the ball impacting the strings centrally and 8 cm off-center. A two-way ANOVA revealed significant (p < .01) main effects for string tension, impact location, and the interaction of string tension and impact location. Treatment-Contrast Interactions demonstrated one significant (p < .01) difference: The decrease in rebound accuracy from a string tension of 200 to 334 N was significantly different for central versus off-center impacts.
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Effect of String Tension and Impact Location on Ball Rebound Accuracy in Static Tennis Impacts
Duane Knudson
A Classification of Instructional Programs (CIP) Primer for Kinesiology Leaders
Duane Knudson
Classification of Instructional Programs (CIP) codes were designed to report outcomes in higher education by specific disciplines and professions, however, universities, states, and accreditation bodies also use these codes in other ways. This paper describes CIP-2010 usage in higher education and how these codes are used in funding public universities in Texas, and summarizes the American Kinesiology Association/National Academy of Kinesiology recommendations to the National Center for Education Statistics on updating kinesiology-related CIP codes. Kinesiology leaders should be knowledgeable about how CIP codes are often used behind the scenes in a variety of ways that affect our faculty, programs, and the field. Greater use of the term kinesiology in many future CIP codes would benefit the field and individual departments seeking alignment with institutional priorities.
Judicious Use of Bibliometrics to Supplement Peer Evaluations of Research in Kinesiology
Duane Knudson
Peer evaluation of scholarly publications and faculty research agendas is an important responsibility of kinesiology faculty and administrators. These expert disciplinary judgments can be supplemented by the careful use of relevant publication- and scholar-specific bibliometric data. This paper summarizes the misuse of journal-level bibliometrics and the research on more relevant publication- or scholar-specific bibliometrics. Recommendations and examples are presented for use of publication- and scholar-specific metrics as supplementary data for peer evaluation of research in kinesiology. Faculty who are knowledgeable about the meaning and limitations of bibliometrics may effectively use these tools to support judgments and check for potential bias in peer evaluations of research for appointment, tenure, promotion, and awards.
Intrasubject Variability of Upper Extremity Angular Kinematics in the Tennis Forehand Drive
Duane V. Knudson
The intra subject variability of the angular kinematics of the wrist and elbow joints in the tennis forehand drive were studied. Two varsity tennis players were filmed as they performed flat forehand drives. The DLT method of 3-D reconstruction was used to measure the angular motion of the upper extremity for eight strokes to assess the intra subject variability of selected kinematic variables. Curves were synchronized to impact and averaged. Wrist and elbow angular position data were quite consistent, with curve coefficients of variation (CV) less than 5.9%. The consistent angular positions during the forward stroke did not result from highly consistent patterns of angular velocities or accelerations. For both the wrist and elbow joints, intra subject variability increased for the angular velocity (CV = 90.6%) and angular acceleration (CV = 129.5%) curves. Biomechanical studies comparing derivatives or kinetic variables across subjects may have to be interpreted with reference to intra subject variability.
Forces on the Hand in the Tennis One-Handed Backhand
Duane V. Knudson
This study examined the pattern of forces and peak loads on the hands of six advanced and six intermediate level male tennis players as they performed one-handed backhand drives. Two miniature load cells were mounted on a midsized graphite racket. The force on the thenar and hypothenar eminences of the hand were sampled at 1000 Hz. Forces on the thenar eminence in preparation for impact were significantly larger and less variable for the advanced subjects. Postimpact peak forces did not differ across skill level and were smaller than the loads reported for forehand drives. The significantly lower thenar forces the intermediate subjects used in preparation for impact may provide less resistance to the acceleration of the racket created by ball impact. A large impact acceleration may be related to a rapid stretch of the wrist extensors, which has been hypothesized to be the cause of tennis elbow.
Promoting Active-Learning Instruction and Research (PALIR) in Kinesiology Departments
Duane Knudson and Karen Meaney
This article describes the implementation and evaluation of an initiative to promote active learning through facility renovation and faculty training. Twenty faculty representing a variety of academic areas from 2 departments participated in a 3-part active-learning professional development workshop series. Department of Health and Human Performance faculty (N = 14) teaching 19 courses and 416 of the students in the new active classroom were surveyed on their attitudes on the facilities, room design, professional development, and active-learning instruction. Consistent with previous active-learning research, there were subtle differences between student and faculty perceptions of the importance of renovation features, active-learning exercises, and philosophy of the learning process. The initiative was effective in helping predisposed faculty to implement active-learning experiences in their classes and engaging in more scholarship of teaching and learning, as well as enhancing the visibility of the department as a leader in active learning and the scholarship of teaching and learning at the university.
Measuring Learning and Promoting Academic Integrity in Online Instruction
Duane Knudson and Melissa Bopp
The COVID-19 pandemic shifted kinesiology courses into more hybrid and online delivery, creating new challenges and opportunities for evaluating learning and online testing. Research using the Biomechanics Concept Inventory indicates that both high-tech and low-tech active learning experiences implemented in hybrid and online formats in biomechanics courses improve student learning above levels for lecture alone. However, online pre- and posttesting using concept inventories or major exams are vulnerable to cheating. Experience and research on proctoring online testing indicate only partial success in detecting cheating absent substantial faculty commitment to investigate suspicious behavior. These difficulties with online testing provide an opportunity for kinesiology faculty to implement more authentic, holistic assessments that are less vulnerable to violations of academic integrity. The importance of well-designed, rigorous assessment methods that uphold academic integrity standards will continue to evolve as kinesiology departments expand online learning.
Kinesiology Review’s Scholarly Influence: An Audit of Its First Decade
Duane Knudson
This study documented the scholarly influence of the first 10 years (2012–2021) of Kinesiology Review (KR). Publication, indexing, and citation data were collected from Google Scholar, the KR editor and website, and two open services using Scopus bibliometric data. KR published 356 articles with recent acceptance rates and median initial review times of 30%–55% and 63–85 days, respectively. KR is indexed in five databases, with searches of Google Scholar indicating 92% have received citations by April 5, 2023. The top 36 (10%) cited articles received a total of 2,533 Google Scholar citations. Top cited KR articles had medians of 50 citations and eight citations/per year over 8 years since their publication, as well as 2021 SCImago Journal Rank and SNIP (source-normalized impact per paper) values similar to many kinesiology journals. There was broad subdisciplinary representation with top cited articles from Behavioral/Social Sciences, Biomedical Sciences, Interdisciplinary/Other, and Humanities. KR makes influential contributions synthesizing kinesiology’s interdisciplinarity knowledge.
Forces on the Hand in the Tennis Forehand Drive: Application of Force Sensing Resistors
Duane V. Knudson and Scott C. White
Two force sensing resistor force transducers were utilized to measure the forces on the hand of seven skilled tennis players performing the tennis forehand drive. Repeatable gripping force patterns were recorded for the subjects given the experimental protocol used for the study. The magnitude of the peak postimpact force on the hand was highly variable, ranging from 4 to 309 N, and was found to be related to high-frequency vibrations of the racket. There was less variability in the magnitude of preimpact gripping forces, indicating that the subjects utilized a consistent gripping pattern in preparation for impact. The large within- and between-subject variability of postimpact forces warrant further study in order to establish the range of loadings in tennis play that may be related to overuse injuries.
Citation of Evidence for Research and Application in Kinesiology
Duane Knudson, Bruce Elliott, and Tim Ackland
Applied research in kinesiology that can truly inform professional practice places high demands on researchers. Clear citation of research evidence is required to design meaningful research and is particularly important in the interpretation of evidence in proposing how the new results may be applied in sport, exercise, or physical activity. This paper summarizes principles for accurate citation of research evidence in justifying and designing applied research in kinesiology; it also proposes an evidence-based practice approach for interpreting the strength of evidence for the application potential of research results. Improved application of kinesiology research is important to advance recognition of the field and support for kinesiology professions.