Digital Commons Network^™

Effect Of Amputation On Muscle Structure Properties In A Rabbit Model, Roy Caleb Stubbs

Masters Theses

After amputation, muscles in the residual limb are detached from their insertion points and no longer span the missing joints. Our objective was to quantify the effect of amputation-induced disuse on residual muscle structure, an indirect indicator of muscle force-generating capacity. One hind paw was surgically removed at the ankle joint of ten rabbits. At two weeks (n=5) and 4 weeks (n=5) post-amputation and for select muscles (gastrocnemius, soleus, tibialis cranialis, extensor digitorum, and flexor digitorum superficialis), we measured and computed several muscle structure properties. Additionally, we qualitatively assessed the muscle fiber appearance of histological samples at each timepoint. At …

The Effects Of Footwear Longitudinal Bending Stiffness On The Energetics And Biomechanics Of Uphill Running, Justin Angelo Ortega

Masters Theses

There has been a prevalence of long-distance running footwear incorporating carbon-fiber plates within their midsoles, effectively increasing their longitudinal bending stiffness (LBS). This modification of modern racing footwear has occurred concurrently with large improvements in running times (Bermon et al., 2021), putting into question how these footwear components affect performance (Muniz-Pardos et al., 2021). The current literature has investigated this at level running, but with the increasing popularity of trail running, it is of interest to investigate whether the benefits found during level running translate to graded running. Therefore, the overall aim of this study was to investigate the effects …

Therapeutic Intervention Or Rider Influence On The Electromyographic Activity And Kinematics Of Horses, Karen L. Shaw

Masters Theses

Core strengthening and postural stability are desired outcomes of certain therapeutic exercises performed in horses. This study aimed to quantify changes in muscle activation at a walk and trot in horses traveling over eight consecutive ground poles evenly spaced (at 30 inches for walk and 48 inches for trot) in parallel fashion in a straight line, and with hindquarter and abdominal elastic resistance bands applied at 25% stretch. Surface electromyography (sEMG) data were collected for the longissimus dorsi and rectus abdominus muscles in six horses. A 2x2 repeated measures ANOVA was performed for each muscle to test for significant differences …

Visuomotor Adaptation During Asymmetric Walking, Charles Napoli

Masters Theses

Necessary for effective ambulation, head stability affords optimal conditions for the perception of visual information during dynamic tasks. This maintenance of head-in-space equilibrium is achieved, in part, by the attenuation of the high frequency impact shock resulting from ground contact. While a great deal of experimentation has been done on the matter during steady state locomotion, little is known about how head stability or dynamic visual acuity is maintained during asymmetric walking.

In this study, fifteen participants were instructed to walk on a split-belt treadmill for ten minutes while verbally reporting the orientation of a randomized Landolt-C optotype that was …

Impact Of Parity On Gait Biomechanics, Bekah P. Stein

Masters Theses

Background: Symptomatic knee osteoarthritis (OA) is an incurable condition that affects nearly 50% of adults, and women are twice as likely as men to develop OA. Throughout pregnancy, women experience large changes in morphology and gait mechanics, as well as changes in joint loading. It is possible these adaptations could cause lasting changes postpartum, which may potentially contribute to initiation of OA, thereby increasing the overall risk of OA for women.

Purpose: This exploratory study looked to identify differences between lower limb gait mechanics of healthy nulliparous women and healthy parous women.

Methods: 28 healthy female participants (14 parous, 14 …

Archery's Lasting Mark: A Biomechanical Analysis Of Archery, Tabitha Dorshorst

Masters Theses

The physical demands of archery involve strenuous movements that place repetitive mechanical loads on the upper body. Given that bone remodels in response to mechanical loading (Ruff, 2008), it is reasonable to assume that repetitive bow and arrow use impacts upper limb bone morphology in predictable ways. The introduction and increased use of archery have been suggested to impact bilateral humeral asymmetry (Rhodes and Knüsel, 2005; Thomas, 2014). However, this claim is yet to be tested in vivo. This project aims to use kinematic and electromyographic approaches to validate claims inferring that, 1. archery places mechanical loading on the non-dominant …

The Effects Of An Overhead Goal And Movement Anticipation On Lower Extremity Biomechanics And Muscle Activation Patterns, Michael O'Dwyer

Masters Theses

Noncontact anterior cruciate ligament (ACL) injury is becoming more common among sport-related injuries. Several "high-risk" movements such as landings and cutting have been associated with ACL injury along with several biomechanical risk factors. These risk factors, specifically at the hip, knee, and neuromuscular abnormalities (unbalanced quadriceps-hamstrings activation ratios) have also been identified as possible causes that lead to ACL injury. Females are nearly 2.5 times more likely to experience an ACL injury while playing volleyball when compared to their male counterparts. While research continues to investigate the reasoning for this injury, the results may not be accurate to what athlete's …

Effects Of Increased Step Width On Knee Biomechanics In Healthy-Weight And Obese Populations During Inclined And Declined Walking, Daniel Sample

Masters Theses

The purpose of this study was to investigate effects of preferred step width and increased step width modification on knee biomechanics, specifically peak knee abduction and extension moments, of obese and healthy-weight participants during incline and decline walking. Seven healthy weight participants and six obese participants categorized by BMI values performed five walking trials on level ground and a 10° inclined and declined instrumented ramp system. Two AMTI force platform(s) were used to collect GRF data (1200 Hz, AMTI,). 3D kinematic data were collected a motion capture system (240 Hz, Vicon). All data were imported into 3D data analysis software, …

Microenvironment Regulates Fusion Of Breast Cancer Cells, Peiran Zhu

Masters Theses

Fusion of cancer cells has been observed in tumors for more than a century and is thought to contribute to tumor development and drug resistance. The low frequency of cell fusion events and the instability of fused cells have hindered our ability to understand the molecular mechanisms that govern cell fusion. We have developed a patterned gel system that can isolate cell fusion events and we demonstrate that several breast cancer cell lines can fuse into multinucleated giant cells in vitro, and the initiation and longevity of fused cells can be regulated solely by biophysical factors. Dynamically tuning the adhesive …

Testing The Arousal Hypothesis: The Effect Of Music On Arousal As Measured By Electrodermal Activity During Verbal Processing, Meghan E. Feeman

Masters Theses

The purpose of this thesis project is to assess the arousal hypothesis by implementing an auditory stimulus (music) at various times during a task (Verbal Processing section of the GRE) to analyze changes in arousal, as measured by electrodermal activity (EDA). Testing is administered for one hour with music implemented before testing and twice during testing. EDA levels are used to measure physiological response and are collected over the one hour testing period. For analysis, testing material is broken into different time blocks to assess arousal levels through mean slope, mean skin conductance level (SCL), mean skin conductance response (xSCR), …

The Effect Of Good Form Running Gait Retraining On Lower Extremity Kinematics And Ground Reaction Forces, Alyssa Schaefbauer

Masters Theses

Running is a popular activity for those trying to get in shape, stay fit, and improve overall health. As running has increased in popularity over the past couple of decades, so has the number of running related injuries. (Higginson, 2009; Statistics and Research, 2016). Interest in running gait research has also increased to address and understand the running related injuries. In addition to reducing injuries, the search for an optimal running form that will improve efficiency is being pursued (Davis, 2005). Good Form Running has become an increasingly popular school of running that seeks to fulfill these needs, but its …

Effects Of Synthetic Turf Systems With And Without A Shock Pad On Lower Extremity Biomechanics During A 90° Cutting Movement With Differing Approach Velocities, Thomas Kenneth Elvidge

Masters Theses

The purpose of this study was to examine differences in lower extremity kinematics and kinetics on two different synthetic turf systems (turf only and turf with a shock pad) for two approach velocities (3.0 and 4.0 m/s) during a 90° cutting movement. Twelve recreational male American football and soccer players were recruited to perform five trials for each of the four conditions. A three-dimensional motion analysis system synchronized to a force platform was used to collect marker coordinate and ground reaction force (GRF) data respectively. A 2 x 2 (surface x approach velocity) ANOVA was used to analyze kinematic and …

Kinematic Analysis Of Trunk Coordination Throughout The Rowing Stroke Sequence, Mcdaragh Rose Minnock

Masters Theses

Rowing at the elite level requires proper sequencing of the rowing stroke so that the rower is able to produce an efficient stroke while protecting oneself from potential injuries. The cyclic motion of the rowing stroke sequence at low loads often results in overuse injuries, specifically in the lower back. Kinematic data of rower’s pelvis-lumbar-thoracic spine were collected using inertial measurement sensors. An incremental step-test was conducted to observe the influence of increasing intensities on the lumbar-pelvis and lumbar-thoracic segments coordination and coordination variability. This study provides a new way of quantifying rowing kinematics using vector coding. The vector coding …

Gait Changes During Exhaustive Running, Nathaniel I. Smith

Masters Theses

Runners adopt altered gait patterns as they fatigue which may increase energy expenditure and susceptibility to certain overuse injuries. Previous investigations have described changes in muscle performance and kinematic gait variables resulting from running fatigue. The purpose of this investigation was to characterize changes in joint moment patterns that develop as runners fatigue in order to better understand the kinetic bases for kinematic fatigue effects. It was hypothesized that when fatigued, runners would demonstrate increases in stance time, peak stance phase knee flexion angle, peak knee extension moment, peak swing phase hip flexion moment, and hip extension and plantarflexion angular …

Does Footfall Pattern In Forefoot Runners Change Over A Prolonged Run?, Carl W. Jewell

Masters Theses

There has been much debate on the benefits of a forefoot versus rearfoot strike pattern in distance running in terms of performance and injury prevalence. Shock attenuation occurs more prominently in soft tissues at impact in forefoot runners compared to the passive skeletal loading in rearfoot runners. Recent studies indicate that a forefoot strike pattern may not be maintainable over long distance efforts. Therefore, this study tested the hypothesis that habitual forefoot runners could not maintain their strike pattern throughout a prolonged, intensive run.

Fourteen forefoot runners ran to voluntary exhaustion on an instrumented force treadmill (average run duration: 15.4±2.2 …

Kinetic Asymmetries During Submaximal And Maximal Speed Running, Devon H. Frayne

Masters Theses

An important issue for sports scientists, coaches and athletes is an understanding of the factors within a running stride that can enhance or limit maximal running speed. Previous research has identified many sprint-related parameters as potential kinetic limiters of maximal Center of Mass velocity (Chapman and Caldwell, 1983b; Weyand et al., 2001). Bilateral asymmetry is present for many of these parameters during running; however the degree to which such asymmetries change as running speed increases is unknown. It was hypothesized that asymmetries in key sprinting parameters would be larger at maximal speed than all other tested speeds. Kinematics and kinetics …

Biomechanical Differences Of Two Common Football Movement Tasks In Studded And Non-Studded Shoe Conditions On Infilled Synthetic Turf, Elizabeth Anne Brock

Masters Theses

The purpose of this study was to examine kinematic and kinetic differences in three shoe conditions (traditional football shoes with natural and synthetic turf studs and a neutral running shoe) during two common football movements (a 180° cut and a land-cut movement) on infilled synthetic turf. Fourteen recreational male football players performed five trials in all three shoe conditions for a 180° cut as well as a land-cut maneuver. The kinematic and kinetic variables were analyzed with a 3 x 2 (shoe x movement) repeated measures analysis of variance (ANOVA, p<0.05). Peak free moment was significantly greater for the land-cut trials (p<0.001). Vertical GRFs were significantly greater for the land-cut trials (p<0.001). A cleat x movement interaction was seen for time to vertical impact GRF (p=0.048). A cleat main effect was found for time to vertical impact between natural turf cleat and synthetic turf cleat (p=0.019). Vertical loading rate was significantly greater in land-cut trials. Peak medial GRFs showed a significant cleat x movement interaction (p=0.002). The results from this study suggest that land-cut movement elicit greater vertical GRF and vertical impact loadings rates. The running shoe had significantly less dorsiflexion range of motion (ROM) than the synthetic turf studs. A significant cleat main effect was found for peak eversion velocity (p=0.005). Post hoc comparisons showed that it was significantly smaller in shoe than that natural turf stud (p=0.016) and synthetic turf stud (p=0.002). In general, there was a lack of differences between the shoe conditions for GRFs and kinematic variables. For the 180° cut movement, natural turf studs produced lowest peak medial GRF compared to the synthetic turf studs and the shoe. The results from this study suggest that land-cut movement elicit greater vertical GRF and vertical impact loadings rates. In general, there was a lack of differences of GRFs and kinematic variables between the shoe conditions. For the 180° cut movement, natural turf studs produced lowest peak medial GRF compared to the synthetic turf studs and the shoe. Overall, increased GRFs, especially in combination with rapid change of direction and deceleration may increase the chance of injury.