Kinesiology Commons^™

Temporal Structure Of Variability Reveals Similar Control Mechanisms During Lateral Stepping And Forward Walking, Shane R. Wurdeman, Nikolaos Stergiou

Journal Articles

Previous research exploring a lateral stepping gait utilized amount of variability (i.e. coefficient of variation) in the medial-lateral (ML) and anterior-posterior (AP) direction to propose that the central nervous system’s active control over gait in any direction is dependent on the direction of progression. This study sought to further explore this notion through the study of the temporal structure of variability which is reflective of the neuromuscular system’s organization of the movement over time. The largest Lyapunov exponent (LyE) of the reconstructed attractors for the foot’s movement in the AP and ML was calculated. Results revealed that despite the obvious …

Biomechanical Testing Of Salter-Harris Fractures Type I And Ii In The Distal Femur And Proximal Tibia, Margeaux Rogers

All Theses

Salter-Harris fractures of the proximal tibia and distal femur are common in pediatric patients that present to orthopedic surgeons. Salter-Harris type I fractures are characterized by breaks that extend only through the physis while Salter-Harris II fractures are the most common, accounting for 85% of Salter-Harris fractures, and extend past the growth plate, exiting through the metaphyseal bone1. Fixation of these fracture types can be accomplished using a variety of methods including the use of Kirschner wires, cannulated screws, and a combination of both materials. Stability of fracture fixation is of utmost importance as persistent motion at the fracture margin …

Humeral Torsion And Shoulder Biomechanics: Comparison Of A Novel Ultrasonographic Technique With The Computed Tomography Benchmark, Bryan Thurston

All Theses

The rotation angle between the proximal and distal axes of long bones is known as torsion, and it is thought to be indicative of the forces applied to the bone during growth. The humerus, for example, develops an internal twist or antetorsion, as daily activities are anterior to the body. However, the strong posterior stress induced by an overhead throwing motion may counteract this internal twist in young athletes and cause prominent bilateral dimorphism.
To measure torsion in these young athletes, a new technique using ultrasound has been developed and implemented in clinical practice. However, before widespread use in diverse …

An Analysis Of Firearms Training Performance Among Active Law Enforcement Officers, John Thomasson

Graduate Theses and Dissertations

Firearms proficiency is an implicit expectation, held by the public of police officers, due to presumption that the required firearm training is an adequate preparation for a deadly force encounter. However, anecdotal evidence and available data on police shootings suggest that conventional, unrealistic training methods are wholly inadequate. To present stress into firearms training, some departments have opted for exercises such as physical exertion and shoot-house training as a substitute for realistic simulation of force-on-force confrontations.

To determine whether such exercises are comparable, an observation of performance and heart rate levels was conducted on a group of eight police officers, …

Effects Of Fatigue On Pelvic And Scapular Stabilizers In Overhead Throwing, Julie Sherrill

Health, Human Performance and Recreation Undergraduate Honors Theses

Human movement is based on proximal to distal sequencing of the kinetic chain. Efficiency of the shoulder is dependent upon the stability and function of the pelvis and scapula. PURPOSE: To determine if pelvic and scapular muscle activations are altered in overhead throwing following fatigue. METHODS: Eleven [19.2 ± 1.0 years; 168.9 ± 6.6 cm; 68.9 + 8.7 kg] softball players volunteered. Surface electromyographic [sEMG] electrodes were placed on bilateral gluteus medius, throwing arm latissimus dorsi, lower trapezius [LT], middle trapezius [MT], and serratus anterior [SA]. Participants had to catch a simulated hit ball and perform their positional throw. Infielders …

Investigations Toward Tunability Of Mechanical, Thermal, And Impact Properties Of Thiol-Ene Networks For Novel High Energy Absorbing Materials, Olivia Devon Mcnair

Dissertations

The UV polymerization of thiols with electron rich alkenes is a highly resourceful reaction that has been utilized by scientists within various disciplines to produce an even more versatile display of applications. This dissertation focuses on a newer application, thiol-ene network (TEN) materials for energy absorption devices. TEN networks display a host of positive polymer properties such as low stress, high optical clarity and uniformity, but they also suffer from unfavorable mechanical properties such as low toughness and elongation at break. The poor mechanical properties demonstrated by TENs prohibit them as choice materials for applications requiring thicker material forms, including …

Effects Of Footstrike Pattern On Low Back Posture, Shock Attenuation, And Comfort During Running, Traci L. Delgado, Emilia Kubera-Shelton, Robert R. Robb

UNLV Theses, Dissertations, Professional Papers, and Capstones

Purpose: Barefoot running (BF) is popular in the running community. Biomechanical changes occur with BF, especially when initial contact changes from rearfoot strike (RFS) to forefoot strike (FFS). In addition, changes in lumbar spine range of motion (ROM), particularly involving lumbar lordosis, have been associated with increased low back pain (LBP). However it is not known how changing from RFS to FFS affects lumbar lordosis or LBP. Thus, the purpose of this study was to determine if a change from RFS to FFS would change lumbar lordosis, and/or decrease shock attenuation, and/or change comfort levels in healthy recreational/experienced runners.

Methods: …

Integrating Biomechanics And Cell Physiology To Understanding Ivd Nutrition And Cell Homeostasis, Yongren Wu

All Dissertations

Back pain associated with degeneration of the intervertebral disc (IVD) is a major public health problem in Western industrialized societies. Degeneration of the IVD changes the osmotic and nutrient environment in the extracellular matrix (ECM) which affects cell behaviors, including: cell proliferation, cell energy metabolism, and matrix synthesis. In addition, a thin layer of hyaline cartilaginous end-plate (CEP) at the superior/inferior disc-vertebral interface was found to play an important role in nutrient supply as well as load distribution in the IVD. Therefore, our general hypothesis is that the CEP regulates the ECM osmotic and nutrient environment which further affects IVD …

The Effects Of Arch Taping On Shock Attenuation During Landing, Shun Jinnouchi

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to investigate the effects of two different arch taping techniques on shock attenuation during landing. Each subject (n=12, age 25.5 ± 3.37 years, height 1.73 ± 0.04 m, mass 82.06 ± 16.23) was instrumented with accelerometers at the leg and forehead (sample rate = 1000 Hz). Subjects performed landings from a 30 cm box under three taping conditions: no tape, Low Dye, and Weave. For each condition, subjects completed 5 landing trials. Rest was provided between each trial and order of conditions was counterbalanced. During each landing, accelerations were recorded at 1000 Hz for …

Effect Of Step Rate On Foot Strike Pattern And Running Economy In Novice Runners, Janae Lynn Richardson

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Purpose—The objective was to examine if step rates ±5% or ±10% of a novice runner's preferred step rate (SR) is sufficient enough to shift a novice runner’s foot strike pattern (FSP) (rear-foot, mid-foot, forefoot) and whether these SR changes produce changes in the rate of submaximal oxygen consumption (VO2). Methods—Foot strike angle (FSA) was recorded using sagittal plane video images and VO2 was measured for novice runners while running on a treadmill at a constant speed during increased and decreased (±5% and ±10%) SR conditions. Foot strike angle was used to predict strike index (SI) (predicted strike index = [FSA …

The Effect Of Implementing A Weight Loss Program On Participant Attendance, Club Usage, And Gym Membership Attrition, Stephanie Bonkemeyer Haymond

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The purpose of this research study was to evaluate the effect of a weight loss program on individual participant attendance, total club usage and membership attrition. This retrospective study involved a fitness gym located in Utah County, Utah with a total membership of 1,100. The number of clients participating in the weight loss program between December 2011 and May 2012 was 36 (32 females and 4 males). A total of 11 clients were analyzed for the individual attendance data as this analysis was limited to only those clients who were gym members one year prior to the implementation of the …

Oxidative Stress For An Acute Bout Of Bikram Yoga In Healthy, Trained Adults, Kimberly Anne Trocio

UNLV Theses, Dissertations, Professional Papers, and Capstones

BACKGROUND:Generation of free radicals resulting in oxidative damage has been linked to cellular damage, aging, and human disease. Many studies have reported that physical exercise can contribute to oxidative stress. Further, exercise in a hyperthermic environment can promote additional oxidative stress. It is important to consider that practices in yoga may be beneficial in reducing oxidative stress according to some studies. The compound effects of exercise and hyperthermic exposure are experienced in the practice of Bikram yoga, the original "hot" yoga. Because Bikram yoga and other hot exercise classes are an increasingly growing fitness trend, it is necessary to investigate …

Effect Of Dehydration On Concomitant Measures Of Cognitive Function And Balance, Stephanie Marie Watson

UNLV Theses, Dissertations, Professional Papers, and Capstones

During activities of daily living, there are demands placed on the body both cognitively and physically. These demands are multiplied when performing an athletic endeavor. Many studies have demonstrated the negative impact dehydration has on cognitive and muscle functions, independently. The purpose of this study is to investigate the effect of dehydration on central nervous system and peripheral nervous system fatigue as expressed through concomitant factors of cognitive function and balance. Subjects were to consist of 20 participates aged 18-35 years old who reported running a minimum of 45 minutes per exercise bout at least 3 times per week. The …

The Acute Effect Of Two Hip External Rotator Stretches On Range Of Motion, Cody Brian Bremner

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to evaluate the acute effect of two commonly used static stretches on hip internal rotation passive range of motion (HIR-PROM). Participants (n=30, 15 male, 15 female; 22±1.8 yrs.; 173.5±8.5cm; 73.8±12.7 kg) were randomly assigned (with gender controlled) to one of three groups: control (C), figure 4 stretch (F4), and modified lunge stretch (ML). Pre and post-test HIR-PROM was measured on each participant's non-dominant hip (28 left, 2 right). HIR-PROM was measured from the prone position; the knee was flexed to 90° and the hip was passively internally rotated. After the pretest, each participant completed …

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 …

Biomechanical Comparison Of A Rounded Outsole Shoe And Traditional Outsole Shoe, Sarah Horsch

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of the study was to determine the effects of shoe outsole design on maximum vertical acceleration and select kinematic parameters during level and uphill walking across phases of stance. Twelve participants, 7 males (75.1±9.3 kg, 173.6±3.6 cm, 22.9±3.5 yrs) and 5 females (56.5±5.1 kg, 158.3±4.5 cm, 25.4±11.1 yrs) granted written consent and preferred walking speed was determined. An accelerometer (480 Hz) was attached to the distal leg to measure maximum leg acceleration (Aleg) and an electrogoniometer (480 Hz) was placed on the back to measure sagittal lumbar motion (LumbarROM). Sagittal video capture (60 Hz) included thigh range of …

Examination Of Lower Extremity Muscle Activity During An Overhand Lacrosse Shot In Females, Brianna Millard

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study intends to provide a basic biomechanical understanding of a specific movement within the sport of lacrosse, an overhand goal shot. Its purpose is to identify the different muscles of the lower extremity and the roles they perform during each phase of the lacrosse shot. Specifically, the study will compare how active muscles are between phases as well as between two different shot speeds. This research provides insight into the importance of timing muscle contractions that lead to a more accurate and faster shot.

Subjects (n=5 females, age: 21.8 ± 2 years, height: 162.56 ± 15.24cm, mass: 63.68 ± …

Predicting Chest Press Strength From A 4rm Triceps Brachii Exercise In Trained Women, Krystina Nadia Moschella

UNLV Theses, Dissertations, Professional Papers, and Capstones

Determining maximal strength is important when developing a resistance exercise program for trained athletes. The most frequent strength procedure used to evaluate maximum strength is the 1RM test. However, risk of injury from a 1RM test increases for the athletes, therefore a 4RM test is used in the following study. The purpose of the study is to test whether there is a linear relationship between the bench press and the triceps rope extension exercise. A secondary purpose is the development of a prediction equation for the purpose of prescribing bench press exercise loads from triceps brachii loads using a 4RM …

Additive Effects Of An External Focus And Enhanced Expectancy In Learning A Motor Skill, Luigi Antonio Pascua

UNLV Theses, Dissertations, Professional Papers, and Capstones

An external focus of attention in has been shown to produce better performance in practice and retention of a motor skill when compared to an internal focus or control conditions in which no attentional focus cues are given to the learner (for a review, see Wulf, 2012). Enhancing learner expectancy (e.g., via positive feedback) has also been shown to improve learning (e.g., Lewthwaite & Wulf, 2010). This study sought to investigate whether combining the positive effects of an external focus of attention with an enhanced learner expectancy (through positive social-comparative feedback) would enhance learning relative to either variable alone or …

Firefighter Fitness-For-Duty Medical Screening: A Peer Review Quality Improvement Pilot, Julie Collings Rochefort

UNLV Theses, Dissertations, Professional Papers, and Capstones

Despite the overwhelming evidence that sudden cardiac death is the most frequent cause of firefighter fatalities, many fire departments do not have a program to measure or maintain basic firefighter fitness and health. This project evaluated and compared medical screening outcomes of four industrial fire brigades within a multinational oil and gas corporation and introduced a quality improvement plan. The goal of this project was to apply the evidence and measure outcomes to determine the most effective way to ensure that firefighters in a corporate setting are healthy. This was accomplished by utilizing established guidelines in developing an educational program …