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Guillaume Mornieux, Elmar Weltin, Monika Pauls, Franz Rott and Albert Gollhofer

Lateral movements with changes of direction are common in many team sports such as soccer or handball. During cutting maneuvers, the athlete performs a complex dynamic task by quickly changing their direction of movement while securing their balance. Knee joint control is an essential requirement

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Logan A. Lucas, Benjamin S. England, Travis W. Mason, Christopher R. Lanning, Taylor M. Miller, Alexander M. Morgan and Thomas Gus Almonroeder

Sports participation has physical, social, and psychological benefits. 1 , 2 Unfortunately, lower-extremity musculoskeletal injuries are common, especially in sports that involve high-impact maneuvers such as landing and cutting (eg, soccer, basketball). 3 , 4 Although the severity of these

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Shelby A. Peel, Lauren E. Schroeder, Zachary A. Sievert and Joshua T. Weinhandl

Noncontact anterior cruciate ligament (ACL) injuries are traumatic injuries that often occur in sports where running, landing, and cutting are primary movements. 1 Nearly 70% of all ACL injuries are classified as noncontact ACL injuries, 2 meaning there is no direct contact to the knee at the

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Kadhiresan R. Murugappan, Michael N. Cocchi, Somnath Bose, Sara E. Neves, Charles H. Cook, Todd Sarge, Shahzad Shaefi and Akiva Leibowitz

Rapid weight loss or “weight cutting” has become commonplace among athletes competing in wrestling, boxing, and martial arts. Mixed martial artists, like other combat sport athletes, are required to adhere to strict weight classifications designed to promote fair play among competitors. Intent

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Xingda Qu, Jianxin Jiang and Xinyao Hu

completely understood. 10 Given that subsensory noise is able to enhance the sensitivity of the human proprioception, it is of interest to examine how subsensory noise affects ACL injury risk in a fatigued state. Landing and cross-over cutting during sports activities impose high additional loads on the

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Kristian M. O’Connor, Sarika K. Monteiro and Ian A. Hoelker

The purpose of this study was to compare the knee joint dynamics for males and females performing constrained cutting tasks to an unanticipated running and cutting maneuver. Sixteen male and 17 female recreational athletes were recruited to perform four cutting tasks; unanticipated run and cut (CUT), stride land and cut (SLC), far box-land and cut (FLC), and close box-land and cut (CLC). Three-dimensional knee joint kinematics and kinetics were recorded. Data were compared across gender and task with a 2 × 4 ANOVA (p < .05), and a factor analysis was performed to examine task relationships. There were significant group mean differences between the tasks and across genders. The factor analysis revealed high correlations between the three constrained tasks, but for variables typically associated with ACL injury risk there was a poor relationship to the CUT task. This was particularly true for the frontal plane variables. The constrained tasks were only moderately useful in predicting cutting mechanics.

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Mark Ludwig and Christoph Bertling

Though visual features such as slow motion, camera angle, or the cutting rate are considered to have great importance for professional media presentation of sports broadcasts and their influence on viewers, there has as yet been little research on the effects of fundamental visual parameters on viewer perception in the field of sport communication. In its primary step, this study researches the effect cutting rates have on the liking of live soccer broadcasts. To this end, an experiment (between-subjects design) with three groups (N = 92) was conducted. All participants received an identical excerpt of a soccer match; however, the number of cuts was systematically altered. A MANCOVA revealed significant effects—for example, a lower cutting rate leads the consumer to perceive less aesthetic appeal and the influences of effects are moderated by fandom. Implications are discussed.

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Dwight E. Waddell, Craig Wyvill and Robert J. Gregor

A field study was performed using a new data collection system looking at upper extremity kinetics during two different cutting tasks, wing vs. tender cuts, in three poultry plants. The Ergonomic Work Assessment System (EWAS) was designed to simultaneously record knife forces (Fx, Fy, and Fz), electromyographic (EMG) activity (forearm flexors/extensors), and goniometric data (wrist flexion/extension), all of which may represent risk factors associated with cumulative trauma disorders, specifically carpal tunnel syndrome (CTS). The objective of this study was to monitor workers in an unencumbered fashion as they performed two different poultry cutting tasks. It was assumed that the variables measured by EWAS would be able to discriminate between the two cuts and quantify possible differences between the two. The results confirmed that EWAS successfully showed significant differences in knife forces between the wing and tender cuts. Knife force differences were also observed between plants for the same cut. Differences in the two cuts were also identified in the EMG and wrist angles. EWAS successfully quantified variables that may represent risk factors associated with CTS in three poultry plants. Knowledge of a better quantitatively described external work environment may enable plants to better design rotation schedules for their deboners.

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Christine D. Pollard, Bryan C. Heiderscheit, Richard E.A. van Emmerik and Joseph Hamill

The purpose of this study was to determine if gender differences exist in the variability of various lower extremity (LE) segment and joint couplings during an unanticipated cutting maneuver. 3-D kinematics were collected on 24 college soccer players (12 M, 12 F) while each performed the cutting maneuver. The following intralimb couplings were studied: thigh rotation (rot)/leg rot; thigh abduction-adduction/leg abd-add; hip abd-add/knee rot; hip rot/knee abd-add; knee flexion-extension/knee rot; knee flx-ext/hip rot. A vector-coding technique applied to angle-angle plots was used to quantify the coordination of each coupling. The average between-trial standard deviation of the coordination pattern during the initial 40% of stance was used to indicate the coordination variability. One-tailed t-tests were used to determine differences between genders in coordination variability for each coupling. Women had decreased variability in four couplings: 32% less thigh rot/leg rot variability; 40% less thigh abd-add/leg abd-add variability; 46% less knee flx-ext/knee rot variability; and 44% less knee flx-ext/hip rot variability. These gender differences in LE coordination variability may be associated with the increased incidence of ACL injury in women. If women exhibit less flexible coordination patterns during competition, they may be less able to adapt to the environmental perturbations experienced during sports. These perturbations applied to a less flexible system may result in ligament injury.

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Michael A. Samaan, Matthew C. Hoch, Stacie I. Ringleb, Sebastian Bawab and Joshua T. Weinhandl

The aim of this study was to determine the effects of hamstrings fatigue on lower extremity joint coordination variability during a sidestep cutting maneuver. Twenty female recreational athletes performed five successful trials of a sidestep cutting task preand postfatigue. Each participant completed an isolated hamstrings fatigue protocol consisting of isokinetic maximum effort knee flexion and passive extension contractions. Vector coding was used to examine hip and knee joint couplings (consisting of various planar motions) during the impact and weight acceptance phases of the sidestep cut stance phase. Paired t tests were used to analyze differences of each phase as an effect of fatigue, where alpha was set a priori at .05. The hip rotation/knee rotation coupling exhibited a significant decrease in coordination variability as a function of fatigue in both the impact (P = .015) and weight acceptance phases (P = .043). Similarly, the hip adduction-abduction/knee rotation coupling exhibited a significant decrease in coordination variability in the weight acceptance phase (P = .038). Hamstrings fatigue significantly decreased coordination variability within specific lower extremity joint couplings that included knee rotation. Future studies should be conducted to determine if this decrease in coordination variability is related to lower extremity injury mechanisms.