Biomechanics Commons^™

An Evaluation Of Kinematic Variables During Stance Phase Of A Training Endurance Run, Joshua Paul Bailey

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of the study was to evaluate kinematics of the lower extremity during the stance phase of an endurance training run. Fifteen participants (8 male, 7 female; 30.5 ± 8.4 years; 71.8 ± 11 kg; 1.73 ± 0.07 m) reported that they were currently signed up for, or planned on signing up for, an endurance race within the next six months of participation in the study (9 half marathon, 3 marathon, 1 triathlon, 2 21k trail run). All had a weekly running mileage greater than 20 miles (23.8 ±4.6 miles). Participants were required to complete the 15–kilometer training run …

Training Strategies And Movement Assessments In Athletes And Non-Athletes, Matthew David Lewis

Theses and Dissertations--Kinesiology and Health Promotion

This dissertation is composed of three manuscripts based on two studies related to training and assessment methods used to evaluate change and overall quality in measures of performance, postural control, and functional movement. Study one evaluated the effect of sand training on athletic performance and postural control. Study two investigated the effect of scoring strata of the deep squat (DS) component of the Functional Movement Screen (FMS) on the weight-bearing lunge test (WBLT), Star Excursion Balance Test (SEBT), and Lateral Flexion Test (LFT) in 101 male and female college students.

Study one results included significant overall improvements of the five …

Shoulder Impingement In Water Polo Players, Kelly A. Davis

Scripps Senior Theses

Water polo is a highly dynamic and physically demanding sport that has heretofore not inspired nearly as much research as other overhead sports such as baseball or swimming. As in almost all overhead sports, water polo puts its players at high risks for shoulder injuries since the motions required to perform the sport at an optimum level push the limits of normal shoulder function.

Human shoulders are inherently unstable as a tradeoff to their flexibility. Because of this instability, many structures are required to work concurrently to keep the shoulder in place. These structures include muscles, ligaments and cartilages. It …

Formulation To Predict Lower Limb Muscle Forces During Gait, Gil Serrancolí, Jonathan P. Walter, Allison Kinney, A. Barjau, Benjamin J. Fregly, Josep M. Font-Llagunes

Mechanical and Aerospace Engineering Faculty Publications

The human body has more muscles than Degrees of Freedom (DoF), and that leads to indeterminacy in the muscle force calculation. This study proposes the formulation of an optimization problem to estimate the lower-limb muscle forces during a gait cycle of a patient wearing an instrumented knee prosthesis. The originality of that formulation consists of simulating muscle excitations in a physiological way while muscle parameters are calibrated. Two approaches have been considered. In Approach A, measured contact forces are applied to the model and all inverse dynamics loads are matched in order to get a physiological calibration of muscle parameters. …

Optimization Problem Formulation For Predicting Knee Muscle And Contact Forces During Gait, Gil Serrancolí, Jonathan P. Walter, Allison Kinney, Benjamin J. Fregly, Josep M. Font-Llagunes

Mechanical and Aerospace Engineering Faculty Publications

The human body has more muscles than degrees of freedom (DOF), which leads to indeterminacy in the muscle force calculation. In this study, an optimization problem to estimate the lower-limb muscle forces during a gait cycle of a patient wearing an instrumented knee prosthesis is formulated. It consists of simulating muscle excitations in a physiological way while muscle parameters are calibrated.

Effects Of Ankle Immobilization On Lower Extremity Joint Coupling Variability, Kristin M. Gundy

Human Movement Studies & Special Education Theses & Dissertations

Human movement is a complex system that encompasses several factors within the body to create coordination. It is not fully understood how the many degrees of freedom (DOF) of the body organize to create movement. Both internal and external influence how the DOF problem works to produce varying movement goals.

The purpose of this study was to better understand the organization patterns of the body by eliminating a DOF. The ankle joint was immobilized to determine if there were differences at the hip and knee joint couplings. It was hypothesized that there would be an increase in movement variability at …

Effect Of A Lateral Wedge Insole Over A One Week Period In A Healthy Population, Sarah E. Sudheimer

Human Movement Studies & Special Education Theses & Dissertations

Medial knee osteoarthritis is a disease that is projected to affect approximately 45% of the U.S. population and is associated with significant morbidity, chronic pain, and limited activity. Laterally wedged insoles are used as an intervention to laterally shift the mechanical axis of the limb and decrease the external knee adduction moment, possibly indicating a shift in load distribution to the lateral compartment of the knee. The aim of this study was to examine the acute effects of a laterally wedged insole in those with valgus and normally aligned knees and to determine prolonged effects after the insole was worn …

Effect Of Racing Flats On Running Economy In Male Adolescent Runners, Paul Hafen

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to investigate whether running economy differs in racing flats versus standard running shoes in high school cross-country runners. In order to measure running economy the oxygen cost of running (mL O₂∙kg^-1∙min^-1) was measured in 20 male adolescent runners (mean age = 16.25 ± 0.97 years, 5 km best time = 17.52 ± 0.78 min) when running two separate trials at a controlled speed. The speed was determined by estimating treadmill running speed at 85% of each runner's VO_2max. Each trial required the participants to run while …

Effects Of Footstrike On Low Back Posture, Shock Attenuation, And Comfort In Running, Traci L. Delgado, Emilia Kubera-Shelton, Robert R. Robb, Robbin Hickman, Harvey Wallmann, Janet Dufek

Interdisciplinary Research Scholarship Day

To determine if a change from rearfoot strike (RFS) to forefoot strike (FFS) would change lumbar lordosis, influence shock attenuation, or change comfort levels in healthy recreational/experienced runners.

Effects Of Shoe Outsole Design And Incline On Walking Biomechanics, Sarah Horsch, Janet Dufek

Interdisciplinary Research Scholarship Day

The purpose of the study was to examine the effects of incline at foot contact of treadmill walking between rounded outsole (ROS) and traditional outsole (TOS) shoes. A rounded outsole shoe (ROS) is specifically designed with a fulcrum under the sole so that when the mass of the body is over it, the foot is forced to roll anteriorly. Traditional ROS studies have included analyses on bipedal stance single leg standing, muscle
activity during treadmill walking, kinetics during over ground walking, and kinematics after a 6-week accommodation period. Presently, there is no research comparing a ROS and a TOS at …

The Examination Of Ankle Joint Motion Between Barefoot And Minimalist Running Shoes On Various Inclines, Stephanie Lloyd

Undergraduate Review

Recently various sports footwear companies have produced different types of minimalist running shoes to mimic barefoot walking or running such as Vibram FiveFingers and Nike Free Run shoes. The purpose of this study was to examine the range of dorsiflexion and plantarflexion movements at the foot in barefoot conditions in comparison to Vibram FiveFingers and Nike Free Run minimalist shoes to evaluate if the minimalist footwear would affect ankle joint motion on both flat and inclined surfaces. Five elite female runners were chosen to run on a treadmill for 30s at the speed of 3 m/s on an incline of …

Role Of Satellite Cells In Long Term Fiber Type Shifts, Honglu Liu

Lewis Honors College Capstone Collection

Muscle fiber type shifts in respect to satellite cells, muscle stem cells, are not well understood currently. The Peterson Lab has generated a mouse model (PAX7-DTA) that ablates satellite cells to determine if these muscle stem cells contribute to mouse muscle fiber type changes over an eight week period. In the study, control and satellite-cell-ablated mouse groups were split into control and overload groups (via synergist ablation surgery) and placed under similar environmental conditions. Eight weeks post-experiment, muscles were dissected to obtain the plantaris muscles of animals from all groups. Muscle cross-sections obtained were immunohistochemically stained, imaged, quantified by fiber …

Changes In In Vivo Knee Contact Forces Through Gait Modification, Allison Kinney, Thor F. Besier, Amy Slider, Scott L. Delp, Darryl D. D'Lima, Benjamin J. Fregly

Mechanical and Aerospace Engineering Faculty Publications

Gait modification represents a non-invasive method for reducing knee joint loading in patients with knee osteoarthritis. Previous studies have shown that a variety of gait modifications are effective in reducing the external knee adduction moment. The external knee adduction moment is often used as a surrogate measure of medial compartment force. However, a recent study showed that reductions in the external knee adduction moment do not guarantee reductions in medial compartment loads. Therefore, direct measurement of changes in knee contact force is important for determining the effectiveness of gait modifications. A previous study found that medial thrust gait and walking …

An Eccentric Intervention Of The Flexor-Pronator Mass To Impact Overhead Throwing Distance And Velocity, Ricker Stanton Adkins

Online Theses and Dissertations

This study focused on the pronator-flexor mass of the elbow and its role in the overhead throwing motion. This specific muscle group is responsible for primary pronation and flexion at the elbow joint, while also reducing valgus stress from compromising the ulnar collateral ligament.

Twenty-three participants were put through a short throwing progression that was focused on their velocity and overall distance thrown from a standing position. After baseline testing was completed participants underwent a short intervention to determine if the intervention would impact all dependent variables. Experimental and non-experimental groups were compared using a repeated measures ANOVA which found …

Effectiveness Of Group Kickboxing As A Means To Improve Gait And Balance In Individuals With Ms, Kurt Jackson, Kimberly Edginton Bigelow, Christina Cooper, Harold L. Merriman

Mechanical and Aerospace Engineering Faculty Publications

In recent years, there has been a particular emphasis on identifying and delivering appropriate therapeutic interventions that address the significant balance and gait impairments that affect individuals with multiple sclerosis (MS). Group interventions implemented in community settings have been especially of interest, including tai chi classes. Recently, the authors conducted a preliminary study to examine whether group kick-boxing, which requires more vigorous movements, might be a feasible intervention. Initial findings showed promise and led the authors to pursue a more rigorous follow-up study, with the objective of determining whether a 5-week group kickboxing class improved clinical measures of balance and …

Athletic Training Students' Ability To Identify Scapular Dyskinesis, Priscilla M. Dwelly

Graduate Theses and Dissertations

Scapular dyskinesis refers to abnormal movement patterns of the scapula, which have been associated with injury. Previous investigations have validated the scapular dyskinesis test as a visual assessment method using physicians, physical therapists, and certified athletic trainers. Through educational programs, athletic training students should be taught what scapular dyskinesis is and how to identify it. Therefore, the purpose of this investigation was to (a) evaluate entry-level graduate athletic training students' ability to identify scapular dyskinesis, (b) assess their reliability, and (c) determine if they were able to correctly identify the muscles involved in rehabilitating an individual with scapular dyskinesis. Follow-up …

Muscle Contributions To Frontal And Transverse Plane Whole-Body Angular Momentum, Richard R. Neptune, Craig P. Mcgowan, Allison Kinney

Mechanical and Aerospace Engineering Faculty Publications

The purpose of this study was to build upon previous work by analyzing how gravity and individual muscles contribute to frontal and traverse plane whole-body angular momentum. Identifying which muscles are responsible for generating angular momentum has important implications for the diagnosis and treatment of movement disorders.

Agonist And Stabilizer Muscle Activity During A Push Up On Unstable Surfaces, Anthony J. Dyrek

UNLV Theses, Dissertations, Professional Papers, and Capstones

A recent trend among fitness professionals is to have clients perform resistance exercises on unstable equipment. Anecdotally, this is done with the intent that stabilizing and agonist muscles are more active while doing certain exercises on unstable surfaces. However, there are limited data as to whether or not this is the case and no studies have investigated muscle activity while doing the same exercise on surfaces that offer different levels of stability. Therefore, the purpose of this study is to measure electromyography (EMG) during push up exercise performed on unstable surfaces as well as on the ground. Surface EMG was …

The Effect Of Maturation On Hip And Knee Kinetics And Kinematics During An Unanticipated Sidestep Cutting Task In Male Youth Lacrosse Players, Crystal M. Sullivan

Human Movement Studies & Special Education Theses & Dissertations

The incidence of noncontact anterior cruciate ligament (ACL) knee injuries has been studied extensively and has been reported as one of the highest injuries amongst high school and collegiate athletes. Little research has been focused on maturational changes in relation to the risk factors of such an injury. The purpose of this study is to determine if there is a difference between pre-pubescent (PRE), pubescent (MID) and postpubescent (POST) male lacrosse athletes indicated by knee and hip kinetics and kinematics during an unanticipated sidestep cutting task (SS). Thirty-one male participants between the ages of nine and fourteen were recruited and …

Fatigue Effects In Lower Extremity Biomechanics During Unanticipated Sidestep Cutting In Young Adolescent Lacrosse Athletes, Julie Ann Bamberg

Human Movement Studies & Special Education Theses & Dissertations

Over the past decade, youth lacrosse participation has substantially increased across the United States. As well, fatigue has been shown to have a detrimental effect on lower extremity biomechanics, potentially increasing the risk for injury. Yet, the effects of fatigue on lower extremity biomechanics in the young adolescent athletic population have not been addressed. The purpose of this study was to assess the effects of a fatigue protocol [Slow Linear Oxidative Fatigue Protocol (SLO-FP)] on lower extremity biomechanics during a side-step cutting task (SCT) in adolescent male lacrosse athletes. This quasi-experimental design was conducted in a controlled laboratory with 24 …

Pre-Swing Deficits In Forward Propulsion, Swing Initiation And Power Generation By Individual Muscles In Hemiparetic Walking, Carrie L. Peterson, Allison Kinney, Steven A. Kautz, Richard R. Neptune

Mechanical and Aerospace Engineering Faculty Publications

Clinical studies of hemiparetic walking have shown pre-swing abnormalities in the paretic leg suggesting that paretic muscle contributions to important biomechanical walking subtasks are different than those of non-disabled individuals. Three-dimensional forward dynamics simulations of two representative hemiparetic subjects with different levels of walking function classified by self-selected walking speed (i.e., limited community=0.4–0.8 m/s and community walkers=>0.8 m/s) and a speed-matched control were generated to quantify individual muscle contributions to forward propulsion, swing initiation and power generation during the pre-swing phase (i.e., double support phase proceeding toe-off). Simulation analyses identified decreased paretic soleus and gastrocnemius contributions to forward propulsion …

Relationships Between Muscle Contributions To Walking Subtasks And Functional Walking Status In Persons With Post-Stroke Hemiparesis, Allison Kinney, Carrie L. Peterson, Steven A. Kautz, Richard R. Neptune

Mechanical and Aerospace Engineering Faculty Publications

Walking speed is commonly used to predict stroke severity and assess functional walking status (i.e., household, limited community and community walking status) post-stroke. The underlying mechanisms that limit walking speed (and functional walking status by extension) need to be understood to improve post-stroke rehabilitation. Previous experimental studies have shown correlations between paretic plantarflexor output during the pre-swing phase and walking speed and suggest that the paretic hip flexors can compensate in some hemiparetic subjects. Modeling and simulation studies of healthy walking have shown that the ankle plantarflexors, soleus (SOL) and gastrocnemius (GAS), and uniarticular hip flexors (IL) are essential contributors …

Neuromechanical Analysis Of Anterior Cruciate Ligament Risk Factors In Female Collegiate Soccer Athletes, Nelson Cortes

Human Movement Studies & Special Education Theses & Dissertations

The anterior cruciate ligament (ACL) acts in an essential role to prevent anterior tibial displacement when experiencing jump-landing forces that are applied to the lower extremity; more than 100,000 injuries per year in the United States in sport activities that often require landing, deceleration-acceleration, cutting and pivoting actions have been reported. The aim of this study was to examine the nature of any lower limb coupling differences between a drop-jump and a side-step cutting actions, assess kinematic and kinetic differences between three tasks, and evaluate the effects of two landing techniques in biomechanical risk factors while performing two unanticipated tasks. …

The Effects Of Two Different Fatigue Protocols On Lower Extremity Kinematics And Kinetics During An Unanticipated Running Stop-Jump, David L. Quammen

Human Movement Studies & Special Education Theses & Dissertations

Altered neuromuscular control strategies and biomechanical movement risk factors are most likely to contribute to the increased incidence of non-contact ACL injury for female athletes. Neuromuscular control strategies and movement patterns are further altered when the effects of fatigue are present. The purpose of this study was to determine neuromechanical differences between two fatigue protocols [Slow Linear Oxidative Fatigue Protocol (SLO-FP) and Functional Agility Short-Term Fatigue Protocol (FASTFP)] when performing a running stop-jump task (RS). A sample of convenience of fifteen Division I female soccer players (age= 19.2 ± 0.8 years; height= 1.67 ± 0.05 m; mass= 61.7 ± 8.1 …

The Effects Of Two Types Of Fatigue On An Unanticipated Side-Step Cutting Task As Measured By Kinematic And Kinetic Variables, Shawn E. Lucci

Human Movement Studies & Special Education Theses & Dissertations

Fatigue has been shown to alter the neuromechanics of lower extremity. To date, no study has examined the effects of two types of fatigue on kinetics and kinematics. To determine neuromechanical differences between two fatigue protocols [Slow Linear Oxidative Fatigue Protocol (SLO-FP) and Functional Agility Short-Term Fatigue Protocol (FAST-FP)] when performing an unanticipated sidestep cutting task. Fifteen female collegiate soccer players (age=19.2±0.8 years; height=l.67±0.05m; mass=61.7±8.lkg) participated in this study. Participants were free of lower extremity injury at time of participation, and performed five successful trials of a sidestep cutting (SS) task pre and post fatigue protocols. For the SLO-FP, a …

The Effects Of An Anterior Cruciate Ligament Prevention Program And Retention Period On Lower Extremity Biomechanics, Ryan S. Mccann

Human Movement Studies & Special Education Theses & Dissertations

Researchers have attempted to determine the effects of strength, flexibility, agility, and plyometric training, as well as expert feedback on biomechanical risk factors for anterior cruciate ligament (ACL) injuries. Currently, the literature lacks information regarding athletes' ability to retain adaptations made during programs designed to reduce biomechanical risk factors for ACL injuries. The purpose of this study was to determine the effects of a 10-week strength and agility program on lower extremity kinetics and kinematics of collegiate athletes immediately following training and after a 11-week retention period. Ten NCAA Division I female soccer players free of lower extremity injury, volunteered …

Trunk Rotation Movement In Tennis Backhand, Hsin-Chen Fanchiang

All-Inclusive List of Electronic Theses and Dissertations

This study analyzed the effects of gender, strike technique, power level, and trial factors on tennis athletes performing backhand strokes with the incoming ball launched by a serving-stand. Five male and five female college tennis athletes volunteered as subjects. Each subject had 25 data points including joint centers of right and left sides for the 5th metatarsal, lateral malleolus, knees, hips, shoulders, elbows, wrists and MP joints, chin, forehead, seven points on the racket (handle, head, neck, upper right and left rims, and lower right and left rims), and the ball were recorded by two video cameras (60Hz). Each of …

The Effect Of Instruction On Jump-Landing Kinematics In Collegiate Age Female Athletes Over Time, Jena Lynne Etnoyer

Human Movement Studies & Special Education Theses & Dissertations

The use of verbal and video instruction is a simple feedback tool that can be implemented into almost all clinical rehabilitative and prevention programs. The purpose of this study was to determine whether self or a combination of self and expert feedback will have a long term effect on box-drop jump (BDJ), running-stop jump (RS), and sidestep maneuver (SS) lower extremity kinematics (knee flexion, knee valgus, hip flexion, hip abduction) over time in healthy college age female athletes. A repeated measures design was used. Forty-three physically active females (age=21.47±1.55years; height=l.65±0.08m; weight=63.78±12kg) were randomly assigned to three groups; 15 self feedback(S), …

Effects Of Static And Dynamic Flexibility Protocols On Lower Extremity Range Of Motion, Samar K. Mccann

Human Movement Studies & Special Education Theses & Dissertations

The purpose of this study was to compare the effects of either a dynamic or static stretching protocol on range of motion during hip flexion, hip extension, and hip abduction, knee flexion and extension, and ankle dorsiflexion over time. Forty eight physically active participants, 18 males and 30 females (age=21.77±2.77 years, height=l66.60±1 l.70 cm, mass=75.08±16.99 kg) with no history of injury within the last month to the lower extremity, no previous surgery in the lower extremity in the past six months, and a previous experience with both types of stretching protocols volunteered for the study. Each subject performed both stretching …

Effects Of Knee Bracing On Vertical Jumping Performance In Healthy College Aged Males, Rebecca E. Rausch

All-Inclusive List of Electronic Theses and Dissertations

Knee bracing is used at all levels of athletics to prevent or support existing knee injuries; however, little research has been conducted on the effects of knee braces on athletic performance. Therefore, the purpose of this study was to examine how two different types of knee braces, semi-customizable braces and knee sleeves, affect vertical jumping performance. Subjects were nine college aged males who regularly participated in athletic activity. Subjects performed a task consisting of a drop jump from a height of 18 inches, landing in a squat position, followed immediately by a maximal vertical jump while wearing two different knee …