Medicine and Health Sciences Commons^™

The Association Of Dorsiflexion Flexibility On Knee Kinematics And Kinetics During A Drop Vertical Jump In Healthy Female Athletes, Philip Malloy, Alexander Morgan, Carolyn M. Meinerz, Christopher Geiser, Kristof Kipp

Exercise Science Faculty Research and Publications

Purpose

While previous studies have examined the association between ankle dorsiflexion flexibility and deleterious landing postures, it is not currently known how landing kinetics are influenced by ankle dorsiflexion flexibility. The purpose of this study was to examine whether ankle dorsiflexion flexibility was associated with landing kinematics and kinetics that have been shown to increase the risk of anterior cruciate ligament (ACL) injury in female athletes.

Methods

Twenty-three female collegiate soccer players participated in a preseason screening that included the assessment of ankle dorsiflexion flexibility and lower-body kinematics and kinetics during a drop vertical jump task.

Results

The results demonstrated …

Biomechanical Investigation Of Elite Place-Kicking, Chase M. Pfeifer

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Many studies aim to understand the fundamentals of kicking commonly displayed by soccer players [4,6,10,16,17,18,24,25,28,29,30,34,36,38,40]. Of those studies, most are limited to a two-dimensional (2D) analysis using high-speed cameras for position tracking or utilizing electromyography to observe the activity of select muscles [4,6,18,25,29,36]. The few studies that investigate kicking using a three-dimensional (3D) model are limited in their position tracking capabilities and focus mainly on joint flexion potentials and foot speed.

This dissertation is a comprehensive biomechanical analysis (kinematic and EMG) of the field-goal place-kicking techniques of four elite kickers in American football. Data were compared and contrasted with ball …

Walking Pattern In Children With And Without Down Syndrome Via A Force-Driven Harmonic Oscillator Model, Jianhua Wu, Matthew Beerse, Toyin Ajisafe, Huaqing Liang

Physical Therapy Faculty Research

Children with Down syndrome (DS) display poorer kinematic and kinetic patterns of walking than typically developing ( TD) children. However, little is known on neuromuscular control in children with DS during locomotion. A force driven harmonic oscillator (FDHO) model sheds light on general muscular activation with respect to the gravitational load of the thigh-shank-foot system. The K/G ratio derived from this model represents a scaling between the elastic restoring torque from muscles and soft tissues and the gravitational torque from the weight of the leg during walking. The K/G ratio has shown different muscular function in infant walkers and children …

Changes In Sprint Kinetics Or Kinematics Following Static Or Dynamic Stretching, Kristyne Bartel

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to determine the effects of static or dynamic stretching on hip kinematics and kinetics during intermittent sprinting. To achieve this aim, intermittent sprint athletes were asked to complete either a static or dynamic stretch, followed by a repeated-sprint protocol. Hip joint kinematics and performance measures were evaluated during the sprint, including changes that occurred in these variables over the course of the sprint protocol. In addition, hip flexion torque was measured with an isokinetic dynamometer. Ten male (age = 25±2.3 years, 175±3.2 cm, 76.2±2.7 kg) and female (age = 20±1 years, 166±1.3 cm, 60±1.1 …

Reliability Of A Multisegment Foot Model In Shod Running, Austin Coupe

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to determine kinematic and marker placement reliability of the Leardini multisegment foot model (LMFM) for tracking foot kinematics during barefoot and shod running without alteration of footwear. Eleven participants, five males (25.6±5 yrs, 73±15.8 kg, 1.75±0.05m) and six females (22.5±2.9 yrs, 66.6±7.2 kg, 1.71±0.05 m) granted institutionally approved written consent to participate. Three-dimensional motion capture (10 Vicon T40-S cameras) was used to capture kinematic data at 200Hz. Kinetic data was captured with an in-ground force platform (Kistler Instruments AG, Switzerland Model 9281B 60x40cm, 2000Hz). Participants were instructed to run at 3.5m/s ±5%. Velocity was …

The Reliability And Validity Of Physiotherapist Visual Rating Of Dynamic Pelvis And Knee Alignment In Young Athletes, C. Whatman, Patricia Hume, Wayne Hing

Wayne Hing

Purpose: To investigate visual rating of pelvis and knee position in young athletes during lower extremity functional tests. Methods: Pelvis and knee alignment, in 23 athletes, was visually rated by 66 physiotherapists. Peak two-dimensional (2D) and three-dimensional (3D) kinematics were also quantified. Ratings were compared to consensus visual ratings of an expert panel. The consensus ratings were also compared to peak kinematics. Reliability was determined using percentage agreement (PA) and the first order agreement coefficient (AC1). Sensitivity, specificity, diagnostic odds ratio (DOR) and differences in kinematics between groups based on the expert visual ratings were calculated to assess rating validity. …

Kinematics During Lower Extremity Functional Screening Tests In Young Athletes - Are They Reliable And Valid?, Patricia Hume, Wayne Hing, C. Whatman

Wayne Hing

Objective: To determine if lower extremity functional tests are reliable and valid screening tests of lower extremity dynamic alignment in healthy young athletes. Design: Quantitative experimental testere-test. Methods: Peak three-dimensional pelvis and lower extremity kinematics were quantified in 23 uninjured young athletes (11 1 years) during three lower extremity functional tests (Small Knee Bend [SKB], Single Leg SKB and Drop Jump) and Running. A nine camera motion analysis system captured three trials of all tests. All functional tests were repeated by 10 young athletes eight to ten weeks later. Visual 3D and Labview were used to process all data. Intraclass …

Upper Limb Ambidexterity In The Wrestling Snap Down Technique, Nicholas A. Decastro

Undergraduate Review

The sport of wrestling dates back as far as recorded history. Folk style is a subdivision of that ancient sport, considered the most popular form of wrestling in U.S high schools and universities. An important skill used by Folk style wrestlers is the snap down technique. However, there is a lack of scientific literature that examines the kinematic motions of the snap down technique bilaterally. Understanding athletic ambidexterity is an important factor in athletic performance and injury prevention, particularly in wrestling. Therefore, the purpose of the research study was to bilaterally examine the kinematic motions of the upper extremity in …

Biomechanical Analysis Of Race Walking Compared To Normal Walking And Running Gait, Jaclyn D. Norberg

Theses and Dissertations--Kinesiology and Health Promotion

Human locomotion is phenomenon that is extraordinarily complex. It is evident that a complete description of locomotion involves consideration of kinematics, kinetics, and muscle activity of the extremities in all of their various movements. Race walking (RW) is a form of upright locomotion that differs from normal walking and running by its form dictated by the International Amateur Athletics Federation (IAAF). Despite the similarities to both normal walking (NW) and running (RU), RW has not been the subject of equally intensive investigations.

This study explores the comprehensive biomechanics of race walking and how it compares to NW and RU. A …

Weight-Bearing Dorsiflexion Range Of Motion And Landing Biomechanics In Individuals With Chronic Ankle Instablity, Matthew C. Hoch, Kelley E. Farwell, Stacey L. Gaven, Joshua T. Weinhandl

Rehabilitation Sciences Faculty Publications

Context: People with chronic ankle instability (CAI) exhibit less weight-bearing dorsiflexion range of motion (ROM) and less knee flexion during landing than people with stable ankles. Examining the relationship between dorsiflexion ROM and landing biomechanics may identify a modifiable factor associated with altered kinematics and kinetics during landing tasks.

Objective: To examine the relationship between weight-bearing dorsiflexion ROM and single-legged landing biomechanics in persons with CAI.

Design: Cross-sectional study.

Setting: Laboratory.

Patients or Other Participants: Fifteen physically active persons with CAI (5 men, 10 women; age = 21.9 ± 2.1 years, height = 168.7 ± 9.0 cm, mass = 69.4 …

Examination Of Lower Extremity Mechanics During Three Landing Tasks And Injury Prediction Ability Of Those Models As Compared To A Functional Test, Timothy G. Coffey

Theses and Dissertations

Anterior cruciate ligament (ACL) ruptures are one of the most common knee ligament injuries suffered by both male and female athletes. These injuries are severe in nature and also have long-term impacts on activities of daily living. Significant research has been conducted utilizing a drop landing task to attempt to better understand the mechanics behind the injury and to help identify at-risk athletes for targeted intervention. However, there have not been any published standards for the height of the drop landing activity, and previous researchers have also raised some concerns about the ability of a drop landing task to replicate …