Biomechanics Commons^™

Endurance Markers Are Related With Local Neuromuscular Response For The Intact But Not For The Acl Reconstructed Leg During High Intensity Running, Kostas Patras, Giorgos Ziogas, Stavros Ristanis, Elias Tsepis, Vasilis Tsiaras, Nikolaos Stergiou, Anastasios D. Georgoulis

Journal Articles

AIM: It has been demonstrated that the local neuromuscular response during high intensity exercise has a strong relationship with endurance markers. However, a diminished neuromuscular response has been reported for the operated leg in athletes having undergone anterior cruciate ligament reconstruction (ACLR). The purpose of the present study was to examine the relationships between endurance markers and the EMG response during high intensity running in ACLR athletes. METHODS: Fourteen ACLR soccer players underwent a GXT test to volitional exhaustion and a 10-min bout of high intensity running. During the 10-min bout, EMG data were recorded at the 3rd …

Computational Approaches To Understand Phenotypic Structure And Constitutive Mechanics Relationships Of Single Cells, Scott Wood

All Dissertations

The goal of this work is to better understand the relationship between the structure and function of biological cells by simulating their nonlinear mechanical behavior under static and dynamic loading using image structure-based finite element modeling (FEM). Vascular smooth muscle cells (VSMCs) are chosen for this study due to the strong correlation of the geometric arrangement of their structural components on their mechanical behavior and the implications of that behavior on diseases such as atherosclerosis.
VSMCs are modeled here using a linear elastic material model together with truss elements, which simulate the cytoskeletal fiber network that provides the cells with …

Human Movement Variability, Nonlinear Dynamics, And Pathology: Is There A Connection?, Nikolaos Stergiou, Leslie M. Decker

Journal Articles

Fields studying movement generation, including robotics, psychology, cognitive science, and neuroscience utilize concepts and tools related to the pervasiveness of variability in biological systems. The concept of variability and the measures for nonlinear dynamics used to evaluate this concept open new vistas for research in movement dysfunction of many types. This review describes innovations in the exploration of variability and their potential importance in understanding human movement. Far from being a source of error, evidence supports the presence of an optimal state of variability for healthy and functional movement. This variability has a particular organization and is characterized by a …

Is There A Relationship Between Fatigue Questionnaires And Gait Mechanics In Persons With Multiple Sclerosis?, Jessie M. Huisinga, Mary Filipi, Kendra K. Schmid, Nikolaos Stergiou

Journal Articles

Objective: To evaluate reported fatigue levels and gait deficits in patients with multiple sclerosis (MS) to determine the relationships that may exist between fatigue in patients with MS and alterations in gait mechanics.

Design: Cross-sectional.

Setting: Biomechanics laboratory.

Participants: Subjects with MS (n=32) and age- and sex-matched controls (n=30).

Interventions: None.

Main Outcome Measures: Fatigue Severity Scale (FSS), Modified Fatigue Index Scale (MFIS), and 36-Item Short Form Health Survey (SF-36) to assess fatigue and general health. Biomechanical gait analysis was performed to measure peak joint torques and powers in the sagittal plane at the ankle, knee, and hip. Correlations …

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 …

New Insights Into Anterior Cruciate Ligament Deficiency And Reconstruction Through The Assessment Of Knee Kinematic Variability In Terms Of Nonlinear Dynamics, Leslie M. Decker, Constantina O. Moraiti, Nikolaos Stergiou, Anastasios D. Georgoulis

Journal Articles

Purpose

Injuries to the anterior cruciate ligament (ACL) occur frequently, particularly in young adult athletes, and represent the majority of the lesions of knee ligaments. Recent investigations suggest that the assessment of kinematic variability using measures of nonlinear dynamics can provide with important insights with respect to physiological and pathological states. The purpose of the present article was to critically review and synthesize the literature addressing ACL deficiency and reconstruction from a nonlinear dynamics standpoint.

Methods

A literature search was carried out in the main medical databases for studies published between 1990 and 2010.

Results

Seven studies investigated knee kinematic …

From The W-Method To The Canonical-Dissipative Method For Studying Uni-Manual Rhythmic Behavior, Dobromir Dotov, Till D. Frank

Journal Articles

A novel method for the analysis of repetitive limb behavior oscillation is presented. It is based on a model used to account for self-sustained limit cycles that involve energy pumping compensating for dissipative processes. The experiment involved a uni-manual pendulum swinging task paced at five frequencies. The median frequency corresponded to the resonant one for the chosen pendulum and hand parameters. We applied the model-based analysis to explore the relationship between behavioral observables and model parameters not available from previous methods. Oscillation amplitude and energy, and motor variability were the behavioral observables we focused on while energy pumping, attractor strength, …

Gait Variability Of Patients With Intermittent Claudication Is Similar Before And After The Onset Of Claudication Pain, Sara A. Myers, Iraklis Pipinos, Jason Johanning, Nikolaos Stergiou

Journal Articles

Background

Recent research demonstrated that intermittent claudication patients have increased gait variability prior to the onset of claudication. However, it is unknown if these patients experience additional gait adaptations after the onset of claudication. Thus, we sought to determine how gait variability is affected by claudication in an effort to contribute to improved clinical management.

Methods

Twenty-six intermittent claudication patients and 20 controls walked on a treadmill at self-selected speed; intermittent claudication patients were tested before (pain free) and after (pain) the onset of claudication. Variability of the ankle, knee, and hip joint angles was assessed using the largest Lyapunov …

Knee Braces Can Decrease Tibial Rotation During Pivoting That Occurs In High Demanding Activities, Dimitrios Giotis, Vasilios Tsiaras, Stavros Ristanis, Franceska Zampeli, Grigoris Mitsionis, Nikolaos Stergiou, Anastasios D. Georgoulis

Journal Articles

Purpose

The purpose of this study was to investigate whether knee braces could effectively decrease tibial rotation during high demanding activities.

Methods

Using an in vivo three-dimensional kinematic analysis, 21 physically active, healthy, male subjects were evaluated. Each subject performed two tasks that were used extensively in the literature because they combine increased rotational and translational loads on the knee, (1) descending from a stair and subsequent pivoting and (2) landing from a platform and subsequent pivoting under three conditions: (A) wearing a prophylactic brace (braced), (B) wearing a patellofemoral brace (sleeved), and (C) unbraced condition.

Results

In the first …

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 …

An Exploratory Biomechanical Analysis Of The Side-To-Side Swing Patterns Of Three Skilled Switch Hitters, Francesca Marie Castellucci

Master's Theses

The ability to successfully switch hit, or hit a baseball from both sides of the plate, requires a great amount of practice and coordination bilaterally. This study used three-dimensional kinematic and kinetic data to examine the swing patterns of skilled switch hitters in baseball. Three male minor league and division I collegiate switch hitters participated. Subjects stood on force plates and hit baseballs off a tee while their swings were recorded with a three-dimensional optical motion capture system. Each subject performed twenty total swings, ten from the right and ten from the left. The swings were digitally analyzed and the …

Complexity, Coordination, And Health: Avoiding Pitfalls And Erroneous Interpretations In Fractal Analyses, Vivien Marmelat, Didier Delignières

Journal Articles

Background and Objective. The analysis of fractal fluctuation has become very popular because of the close relationships between health, adaptability, and long-range correlations. 1/f noise is considered a “magical” threshold, characterizing optimal functioning, and a decrease or conversely and increase of serial correlations, with respect to 1/f noise, is supposed to sign a kind of disadaptation of the system. Empirical results, however, should be interpreted with caution. In experimental series, serial correlations often present a complex pattern, resulting from the combination of long-range and short-term correlated processes. We show, in the present paper, that an increase in serial correlations …

Systematically Controlling For The Influence Of Age, Sex, Hertz And Time Post-Whole-Body Vibration Exposure On Four Measures Of Physical Performance In Community-Dwelling Older Adults: A Randomized Cross-Over Study, Harold L. Merriman, C. Jayne Brahler, Kurt Jackson

Physical Therapy Faculty Publications

Though popular, there is little agreement on what whole-body vibration (WBV) parameters will optimize performance. This study aimed to clarify the effects of age, sex, hertz, and time on four physical function indicators in community-dwelling older adults (N = 32). Participants were exposed to 2 minutes WBV per session at either 2 Hz or 26 Hz, and outcome measures were recorded at 2-, 20-, and 40-minute post-WBV. Timed get-up-and-go and chair sit-and-reach performances improved post-WBV for both sexes, were significantly different between 2 Hz and 26 Hz treatments (P ≤ 0.05), and showed statistically significant interactions between age and gender …

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.

Electromechanics Of Biological Systems Studied By Scanning Probe Microscopy, Gary Thompson

All Dissertations

The functional role of piezoelectricity and of other modes of electromechanical coupling across the hierarchical structures of biological materials garnered interest many years ago. Many biological materials have been described as exhibiting piezoelectric behavior, from wool fibers to wood planks and even to living mammalian cells, but efforts are on-going towards understanding how electromechanical coupling in biological systems transcends from the molecular to tissue levels.
In pursuit of high-resolution measurements of such hierarchical electromechanical coupling, scanning probe microscopy-based techniques are considered. Piezoresponse force microscopy (PFM) becomes the specific focus of this work, and the nascent development of PFM is reviewed …

Walk-Run Transition Speed And The Relevance Of Loading, Muscular Fatigue, And Human Kinematics: A Comparison Of Human Gait Patterns, Callie Elizabeth Gunderson

Boise State University Theses and Dissertations

INTRODUCTION: The walk-to-run transition (WRT) typically occurs at a preferred transition speed (PTS) of 1.9-2.1ms^-1. Previous research has focused on potential triggers for this transition such as leg length, muscular fatigue, loading rates (LR), and vertical ground reaction forces (VGRFs). Rather than focus on mechanisms responsible for the transition, the purpose of the current study was to determine if basic anthropometrics or gait characteristics are predictive of the WRT. METHODS: Thirty participants were recruited for the current study (n = 13 male, 17 female; n = 11 normal weight, n = 10 overweight, n = …

Comparative Forelimb Muscle Function In Turtles: Tests Of Environmental Variation And Neuromotor Conservation, Angela Rivera

All Dissertations

Novel locomotor functions in animals may evolve through changes in morphology, muscle activity, or a combination of both. The idea that new functions or behaviors can arise solely through changes in structure, without concurrent changes in the patterns of muscle activity that control movement of those structures, has been formalized as the `neuromotor conservation hypothesis'. In vertebrate locomotor systems, evidence for neuromotor conservation is found across transitions in terrestrial species and into fliers, but transitions in aquatic species have received little comparable study to determine if changes in morphology and muscle function were coordinated through the evolution of new locomotor …

The Effects Of A Lumbopelvic Hip Complex Conditioning Program On Dynamic Knee Valgus In Female Tennis Players, Katelyn Marie Roling

Graduate Theses and Dissertations

Female athletes have a four-to-six times greater risk of sustaining a lower extremity injury than their male counterparts (Hewett, 2000). One explanation for the discrepancy in injury rates is increased dynamic knee valgus angles caused by neuromuscular imbalances of the lumbopelvic hip complex (LPHC). The purpose of this study was to determine if implementing a LPHC conditioning program improved neuromuscular deficiencies. Seven female collegiate tennis players competitive at the NCAA Division I level volunteered for the study (19.7 + .95 years, 167.3 + 7.4 cm, and 60.72 kg + 6.71 kg). The subjects participated in a 16 week LPHC conditioning …

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 …

Kinematic And Electromyographic Description Of Baseball And Softball Catching, Hillary Ann Plummer

Graduate Theses and Dissertations

The catcher is actively involved, defensively, in every pitch that is thrown during the duration of a baseball or softball game. Because catchers play such an active role, the outcome of the game can be decided on their ability to keep base runners from stealing and advancing into scoring position. The ability to throw out a stealing runner is a necessary skill that catchers must possess in order to be successful at their position. To keep a base runner from stealing catchers have the option of throwing down to second base from either their stance or their knees. Despite the …

A Biomechanical Analysis Of The Weight Training Squat Using Dartfish Motion Analysis Software, Wesley Kephart

Undergraduate Research Conference

Biomechanical analysis of Weight Training Squat to ensure proper technique to avoid injury. This study used the Dartfish Motion Analysis Software to monitor two subjects form and technique during the lift.

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 …

Sensory Information Utilization And Time Delays Characterize Motor Developmental Pathology In Infant Sitting Postural Control, Joan E. Deffeyes, Regina T. Harbourne, Wayne A. Stuberg, Nikolaos Stergiou

Journal Articles

Sitting is one of the first developmental milestones that an infant achieves. Thus measurements of sitting posture present an opportunity to assess sensorimotor development at a young age. Sitting postural sway data were collected using a force plate, and the data were used to train a neural network controller of a model of sitting posture. The trained networks were then probed for sensitivity to position, velocity, and acceleration information at various time delays. Infants with typical development developed a higher reliance on velocity information in control in the anterior-posterior axis, and used more types of information in control in the …

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 …

The Influence Of Visual Perception Of Self-Motion On Locomotor Adaptation To Unilateral Limb Loading, Mukul Mukherjee, K.-C. Siu, Dimitrios Kastavelis, Pierre B. Fayad, Nikolaos Stergiou

Journal Articles

Self-perception of motion through visual stimulation may be important for adapting to locomotor conditions. Unilateral limb loading is a locomotor condition that can improve stability and reduce abnormal limb movement. In the present study, the authors investigated the effect of self-perception of motion through virtual reality (VR) on adaptation to unilateral limb loading. Healthy young adults, assigned to either a VR or a non-VR group, walked on a treadmill in the following 3 locomotor task periods—no load, loaded, and load removed. Subjects in the VR group viewed a virtual corridor during treadmill walking. Exposure to VR reduced cadence and muscle …

Approximate Entropy Used To Assess Sitting Postural Sway Of Infants With Developmental Delay, Joan E. Deffeyes, Regina T. Harbourne, Wayne A. Stuberg, Nikolaos Stergiou

Journal Articles

Infant sitting postural sway provides a window into motor development at an early age. The approximate entropy, a measure of randomness, in the postural sway was used to assess developmental delay, as occurs in cerebral palsy. Parameters used for the calculation of approximate entropy were investigated, and approximate entropy of postural sway in early sitting was found to be lower for infants with developmental delay in the anterior–posterior axis, but not in the medial–lateral axis. Spectral analysis showed higher frequency features in the postural sway of early sitting of infants with typical development, suggesting a faster control mechanism is active …

Velocity At Lactate Threshold And Running Economy Must Also Be Considered Along With Maximal Oxygen Uptake When Testing Elite Soccer Players During Preseason, Giorgos Ziogas, Kostas Patras, Nikolaos Stergiou, Anastasios D. Georgoulis

Journal Articles

Velocity at lactate threshold and running economy must also be considered along with maximal oxygen uptake when testing elite soccer players during preseason. J Strength Cond Res 25(2): 414-419, 2011-Maximal oxygen uptake (V̇o₂max) has been traditionally used to explain physiologic differences among soccer teams of different ranking. However, other endurance markers may have greater discriminatory ability. The purpose of this study was to examine whether velocity at lactate threshold and running economy can be used to better discriminate endurance characteristics of soccer teams of different levels along with V̇o₂max during preseason testing. One hundred twenty-nine professional …

Multiple Sclerosis Affects The Frequency Content In The Vertical Ground Reaction Forces During Walking, Shane R. Wurdeman, Jessie M. Huisinga, Mary Filipi, Nikolaos Stergiou

Journal Articles

Background: Multiple sclerosis is a progressive neurological disease that results in a high incident of gait disturbance. Exploring the frequency content of the ground reaction forces generated during walking may provide additional insights to gait in patients with multiple sclerosis that could lead to specific tools for differential diagnosis. The purpose of this study was to investigate differences in the frequency content of these forces in an effort to contribute to improved clinical management of this disease.

Methods: Eighteen patients and eighteen healthy controls walked across a 10 meter long walkway. The anterior–posterior and vertical ground reaction forces generated …

Knee Range Of Motion: Reliability And Agreement Of 3 Measurement Methods, Paul G. Peters, Michael A. Herbenick, Philip A. Anloague, Ronald J. Markert, L. Joseph Rubino

Physical Therapy Faculty Publications

We conducted a study to compare 3 methods of measuring knee range of motion: visual estimation by physicians, hand goniometry by physical therapists, and radiographic goniometry. We hypothesized that reliability would be high within and across all techniques. We found intrarater and interrater reliability to be satisfactory for visual estimation, hand goniometry, and radiographic goniometry. Interrater reliability across methods did not agree satisfactorily. Between-methods differences in estimating knee range of motion may result from variations in technique among physicians and physical therapists.

A Comparison Of Two Pelvic Floor Muscle Training Programs In Females With Stress Urinary Incontinence: A Pilot Study, Betsy Donahoe-Fillmore, Wendy Chorny, C. Jayne Brahler, Ashley Ingley, Jennifer Kennedy, Valerie Osterfeld

Physical Therapy Faculty Publications

Background: Stress urinary incontinence (SUI) is a condition affecting millions of Americans. Few studies have assessed the benefits of different exercises involved in pelvic floor muscle training (PFMT). Purposte: The purpose of this study was to compare the effects of a traditional PFMT program to an assisted pelvic floor muscle training (APFMT) program that included contraction of hip musculature.