greater reductions in anterior cruciate ligament (ACL) injury risk compared with those that do not include feedback. 1 Various modes of feedback, including expert-provided feedback and self-analysis feedback, have been used to specifically reduce vertical ground reaction force and increase knee
Hayley M. Ericksen, Brian Pietrosimone, Phillip A. Gribble and Abbey C. Thomas
Hai-Jung Steffi Shih, Danielle N. Jarvis, Pamela Mikkelsen and Kornelia Kulig
central nervous system often controls movement variability based on task relevance. For example, expert dancers exhibit greater trunk coordination variability right before landing of bipedal jumps, possibly a combined effect of feedback control from each unique flight characteristic and feedforward
Kristoffer Henriksen, Louise Kamuk Storm, Natalia Stambulova, Nicklas Pyrdol and Carsten Hvid Larsen
. Based on interviews with expert sport psychology practitioners (SPPs), the present study investigates successful and less successful intervention experiences in two main contexts: competitive youth and elite senior sport. Successful sport psychology interventions are sensitized in the sense that they
Erik A. Wikstrom, Cole Mueller and Mary Spencer Cain
LAS. However, there are numerous published expert opinion papers on RTS within the literature. Establishing agreement among such opinions could help to further clinical practice and research into this important area. Objective To determine if there was consensus among published expert opinions that
James Onate, Nelson Cortes, Cailee Welch and Bonnie Van Lunen
A clinical assessment tool that would allow for efficient large-group screening is needed to identify individuals potentially at risk for anterior cruciate ligament (ACL) injury.
To assess the criterion validity of a jumplanding assessment tool compared with 3-dimensional (3D) motion analysis and evaluate interrater reliability across an expert vs novice rater using the Landing Error Scoring System (LESS).
Nineteen female (age 19.58 ± .84 y, height 1.67 ± .05 m, mass 63.66 ± 10.11 kg) college soccer athletes volunteered.
Main Outcome Measurement:
Interrater reliability between expert rater (5 y LESS experience) vs novice rater (no LESS experience). LESS scores across 13 items and total score. 3D lower extremity kinematics were reduced to dichotomous values to match LESS items.
Participants performed drop-box landings from a 30-cm height with standard video-camera and 3D kinematic assessment.
Intrarater item reliability, assessed by kappa correlation, between novice and experienced LESS raters ranged from moderate to excellent (κ = .459–.875). Overall LESS score, assessed by intraclass correlation coefficient, was excellent (ICC2,1 = .835, P < .001). Statistically significant phi correlation (P < .05) was found between rater and 3D scores for knee-valgus range of motion; however, percent agreement between expert rater and 3D scores revealed excellent agreement (range of 84–100%) for ankle flexion at initial contact, knee-flexion range of motion, trunk flexion at maximum knee flexion, and foot position at initial contact for both external and internal rotation of tibia. Moderate agreement was found between rater and 3D scores for trunk flexion at initial contact, stance width less than shoulder width, knee valgus at initial contact, and knee-valgus range of motion.
Our findings support moderate to excellent validity and excellent expert vs novice interrater reliability of the LESS to accurately assess 3D kinematic motion patterns. Future research should evaluate the efficacy of the LESS to assess individuals at risk for ACL injury.
Nahoko Sato, Hiroyuki Nunome and Yasuo Ikegami
In hip-hop dance contests, a procedure for evaluating performances has not been clearly defined, and objective criteria for evaluation are necessary. It is assumed that most hip-hop dance techniques have common motion characteristics by which judges determine the dancer’s skill level. This study aimed to extract motion characteristics that may be linked to higher evaluations by judges. Ten expert and 12 nonexpert dancers performed basic rhythmic movements at a rate of 100 beats per minute. Their movements were captured using a motion capture system, and eight judges evaluated the performances. Four kinematic parameters, including the amplitude of the body motions and the phase delay, which indicates the phase difference between two joint angles, were calculated. The two groups showed no significant differences in terms of the amplitudes of the body motions. In contrast, the phase delay between the head motion and the other body parts’ motions of expert dancers who received higher scores from the judges, which was approximately a quarter cycle, produced a loop-shaped motion of the head. It is suggested that this slight phase delay was related to the judges’ evaluations and that these findings may help in constructing an objective evaluation system.
Masato Hirano, Shinji Kubota, Takuya Morishita, Kazumasa Uehara, Shusaku Fujimoto and Kozo Funase
The aim of this study was to investigate the plasticity of M1 innervating the tibialis anterior muscle (TA) induced by the long-term practice of football juggling using a transcranial magnetic stimulation (TMS) technique. Ten football juggling experts and ten novices participated in this study. Motor evoked potentials (MEP) and the H-reflex were recorded from the right TA during isometric dorsiflexion at 10% of maximum voluntary contraction. The MEP input-output curve of the experts was steeper than that of the novices, and reduced short-interval intracortical inhibition and long-interval intracortical inhibition were observed in the experts. In contrast, the ratio of Hmax to Mmax did not differ between the groups. Our results show that football juggling experts displayed enhanced excitability in the M1 innervating the TA, which was induced by the long-term practice of the ankle movements required to perform football juggling well.
Andrea Bundon, Barry S. Mason and Victoria L. Goosey-Tolfrey
This paper demonstrates how a qualitative methodology can be used to gain novel insights into the demands of wheelchair racing and the impact of particular racing chair configurations on optimal sport performance via engagement with expert users (wheelchair racers, coaches, and manufacturers). We specifically explore how expert users understand how wheels, tires, and bearings impact sport performance and how they engage, implement, or reject evidence-based research pertaining to these components. We identify areas where participants perceive there to be an immediate need for more research especially pertaining to the ability to make individualized recommendations for athletes. The findings from this project speak to the value of a qualitative research design for capturing the embodied knowledge of expert users and also make suggestions for “next step” projects pertaining to wheels, tires, and bearings drawn directly from the comments of participants.
Jeremiah Tate, Hanna True, Barry Dale and Carrie Baker
The high rate of ACL injury has led to the need for large-scale injury risk screening to aid in prevention. Cost and time alternatives to three-dimensional assessments of knee injury risk factors are necessary for largescale, clinical use. The purpose of this study was to determine the expert versus novice interrater reliability and test-retest reliability of the frontal plane projection angle (FPPA) during the single-leg squat (SLS) test. Excellent interrater reliability was demonstrated for session 1 and session 2. Excellent intrarater (i.e., test-retest) reliability was demonstrated for both the novice and expert. The minimal training requirements and excellent reliability of the FPPA during the SLS test make it a key screening tool for large-scale assessment of injury risk.
Melinda A. Solmon and Amelia M. Lee
This study explored the cognitive responses of adapted physical education teachers during lesson planning. The focus was to determine whether expert (n=4) and novice (n=4) teachers varying in experience and expertise differ in the information they need to plan a lesson and how they conceptualize a lesson. Subjects were given information about a fictional class of handicapped students and were asked to plan a lesson. After writing a lesson plan, they were asked to explain it to the experimenter. The results provided clear evidence of the experienced teachers’ superior knowledge base and repertoire of teaching strategies. Their responses were filled with contingency plans based on the actions and abilities exhibited by the students. In contrast, the novices generated plans that were unidirectional and failed to accommodate the range of ability levels in the class.