Biomechanics Commons^™

The Effect Of Cardiorespiratory Fitness On The Assessment Of The Physical Working Capacity At The Fatigue Threshold, Brittney M. Mikkelsen, Jorge Zuniga, William K. Herron, Frances E. Frauso, Anne N. Pulliam

Journal Articles

Purpose: The purpose of this study was to determine if different cardiorespiratory fitness levels (maximal oxygen uptake or VO2max) affect neuromuscular fatigue as measured by the physical working capacity at the fatigue threshold (PWCFT). Methods: Fourteen adults (14 men; mean ± SD; age = 20.79 ± 0.89 years; body weight = 80.7 ± 10.91 kg; height = 178.4 ± 5.29 cm) volunteered to participate in the investigation. Each participant performed an incremental cycle ergometry test to fatigue while electromyographic (EMG) signals were measured from the vastus lateralis (VL) muscle. Mean, standard deviation, and range values were calculated for …

A Complete Kinematic, Kinetic, And Electromyographical Analysis Of The Football Throw In Collegiate Quarterbacks, Kyle R. Bohnert

Theses and Dissertations--Kinesiology and Health Promotion

The biomechanics of the overhead throw has been extensively studied in regards to baseball pitching. However, an understanding of the proper mechanics needed to successfully throw a football has not previously been investigated. Thus, the purpose of this study was to investigate the kinematics, kinetics, and electromyography of the football throws in elite quarterbacks. Three collegiate quarterbacks were evaluated using a multi-camera motion capture system and electromyography electrodes. The results of this study are able to give a breakdown in the types of mechanics needed in each of the phases of the throw. This study demonstrated that during the early …

Central And Peripheral Weight Gain Affect Trunk Kinematics And Lower-Extremity Muscle Activation Differently During Sit-To-Stand, Michelle Christine Walaszek

Theses and Dissertations--Kinesiology and Health Promotion

Background: Obesity-induced alterations in biomechanics and muscle recruitment during activities of daily living, such as sit-to-stand (STS) are often attributed to increases in adipose tissue (AT) mass. Central or peripheral distribution of AT may differently affect biomechanics and muscle recruitment.

Methods: Fifteen healthy, normal weight (BMI 22.4 ± 1.9 kg/m², 24.1 ± 4.2 years) subjects volunteered. External loads equivalent to a 5 kg/m² BMI increase were applied in three conditions: unloaded (UN), centrally loaded (CL), and peripherally loaded (PL). Subjects completed three successful STS movements in a backless chair under each load condition in random order. Motion …

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 …

The Effect Of Posterior Foot Positions On Electromyography, Joint Kinetics And Energetics During A Sit-To-Stand In Young And Older Adults, Eric A. Pitman

Human Movement Studies & Special Education Theses & Dissertations

The sit-to-stand (STS) movement, defined as standing up from a chair to an upright posture, is a common task performed daily. The inability to accomplish this task may lead to dependence, institutionalization and even death in older adults. A common strategy change for the STS is positioning the feet posteriorly by increasing flexion at the knee joint. This reduces the displacement of the center of mass to the base of support while increasing the joint moment of force at the knee while decreasing it at the hip. The aims of this study were to: 1) examine the joint kinetics, joint …

Lower Extremity Biomechanics In Individuals With And Without Previous Hamstring Injury, Jessica A. Mutchler

Human Movement Studies & Special Education Theses & Dissertations

Primary risk factors for hamstrings strains such as fatigue, previous injury and strength deficits have been identified in the research, yet re-injury rates remain high among the physically active. Sub-acute analysis of the hip, knee and ankle biomechanics following a hamstrings strain have been largely overlooked and may provide additional insight into re-injury risks. It was the aim of this dissertation to explore long-term adaptations in walking and running tasks following a hamstrings strain, and to develop a hip endurance test that could be used in future studies.

Project one used a cross-sectional study with test-retest design to develop and …

The Effects Of Muscle Cross-Sectional Area On The Physical Working Capacity At The Fatigue Threshold, Meghan B. Barry, Jorge M. Zuniga, Makenna M. Brown, William M. Garnett, Zachary V. Hadden, Paul K. Nguyen, Geoffrey A. Supplee, Claire J. Svobada

Journal Articles

Purpose: The purpose of this study was to examine the effects of quadriceps cross-sectional area (CSA) of the dominant quadriceps muscle in the assessment of the physical working capacity at the fatigue threshold (PWCFT) during incremental cycle ergometry. Methods: Eighteen adults (9 men and 9 women; mean age ± SD = 20.5 ± 1.04 yr; mean body weight ± SD = 73.9 ± 18.2 kg; mean height ± SD = 172.3 ± 11.5 cm; mean dominant quadriceps CSA ± SD = 68.7 ± 14.5 cm2) performed an incremental cycle ergometry test to exhaustion while the electromyographic (EMG) signals …

Environmental Effects On The Biomechanics And Motor Physiology Of Elastically Powered Movements In Chameleons, Christopher Van Anderson

USF Tampa Graduate Theses and Dissertations

Environmental temperature exhibits profound effects on the activity and ecology of ectotherms through its impact on muscle contractile physiology. While the performance of locomotor behaviors powered by muscle contraction directly decreases by at least 33% over a 10°C drop in body temperature, chameleons are known to feed, presumably with high performance, at body temperatures where sympatric lizard species remain inactive. I propose that ballistic movements that are powered by the recoil of preloaded elastic and collagenous tissues are less thermally dependent than movements that rely on direct muscular power. Despite the reduced thermal sensitivity of the elastic-recoil powered movement, I …

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 …

Electromechanical Delay Of The Knee Flexor Muscles After Harvesting The Hamstrings For Anterior Cruciate Ligament Reconstruction, Stavros Ristanis, Elias Tsepis, Dimitrios Giotis, Franceska Zampeli, Nikolaos Stergiou, Anastasios D. Georgoulis

Journal Articles

Objective: To investigate if harvesting of semitendinosus (ST) and gracilis for anterior cruciate ligament (ACL) reconstruction will have an effect in coordinative firing pattern of the hamstrings under fatigue. We hypothesized that fatigue will increase the electromechanical delay (EMD) of the hamstrings on the harvested site and impair the synchronization between the medial and lateral hamstrings, in terms of muscle activity onsets.

Design: Prospective nonrandomized study. Setting: Institutional. Patients: Twelve ACL reconstructed patients with hamstrings, 2 years postoperatively.

Interventions: The patients performed a fatigue protocol with 25 continuous maximal isometric voluntary contractions of 8-second duration with 2-second …

The Effect Of Music On Robot-Assisted Laparoscopic Surgical Performance, Ka-Chun Siu, I. H. Suh, Mukul Mukherjee, D. Oleynikov, Nikolaos Stergiou

Journal Articles

Music is often played in the operating room to increase the surgeon’s concentration and to mask noise. It could have a beneficial effect on surgical performance. Ten participants with limited experience with the da Vinci robotic surgical system were recruited to perform two surgical tasks: suture tying and mesh alignment when classical, jazz, hip-hop, and Jamaican music were presented. Kinematics of the instrument tips of the surgical robot and surface electromyography of the subjects were recorded. Results revealed that a significant music effect was found for both tasks with decreased time to task completion (P = .005) and total …

Differences In Muscle Activation In The Lower Extremities While Performing Traditional Squats And Non-Traditional Squats, Christopher M. Scotten

Boise State University Theses and Dissertations

Purpose: To determine if muscle activation in the lower back and lower extremities differ when performing traditional squats compared to non-traditional (forward center of pressure on foot) squats. The erector spinae, hamstrings, quadriceps, adductor longus, gastrocnemius, and gluteus maximus muscles were monitored for differences in this study. There are several variations of the back squat and each variation may possibly target muscles differently. Determining if non-traditional squats leads to larger erector spinae muscle activation, which in turn may lead to more lower back fatigue and possible lower back injury is a major aim of this study. Participants: Thirteen healthy males …

Electromyographic Response Is Altered During Robotic Surgical Training With Augmented Feedback, Timothy N. Judkins, D. Oleynikov, Nikolaos Stergiou

Journal Articles

There is a growing prevalence of robotic systems for surgical laparoscopy. We previously developed quantitative measures to assess robotic surgical proficiency, and used augmented feedback to enhance training to reduce applied grip force and increase speed. However, there is also a need to understand the physiological demands of the surgeon during robotic surgery, and if training can reduce these demands. Therefore, the goal of this study was to use clinical biomechanical techniques via electromyography (EMG) to investigate the effects of real-time augmented visual feedback during short-term training on muscular activation and fatigue. Twenty novices were trained in three inanimate surgical …

Robotic Surgery And Training: Electromyographic Correlates Of Robotic Laparoscopic Training, Timothy N. Judkins, D. Oleynikov, N. Karazaki, Nikolaos Stergiou

Journal Articles

Background: Robotic laparoscopic surgery has been shown to decrease task completion time, reduce errors, and decrease training time when compared to manual laparoscopic surgery. However, current literature has not addressed physiological effects, in particular muscle responses, to training with a robotic surgical system. We seek to determine the frequency response of electromyographic (EMG) signals of specific arm and hand muscles with training using the da Vinci Surgical System (dVSS).

Methods: Seven right-handed medical students were trained in three tasks with da Vinci Surgical System over four weeks. These subjects, along with eight controls, were tested before and after …

Robotic Surgery Training And Performance, Kenji Narazaki, D. Oleynikov, Nikolaos Stergiou

Journal Articles

Background: To understand the process of skill acquisition in robotic surgery and to allow useful real-time feedback to surgeons and trainees in future generations of robotic surgical systems, robotic surgical skills should be determined with objective variables. The aim of this study was to assess skill acquisition through a training protocol, and to identify variables for the quantification of proficiency.

Methods: Seven novice users of the da Vinci Surgical System engaged in 4 weeks of training that involved practicing three bimanual tasks with the system. Seven variables were determined for assessing speed of performance, bimanual coordination, and muscular activation. These …

A Motor And A Brake: Two Leg Extensor Muscles Acting At The Same Joint Manage Energy Differently In A Running Insect, Anna N. Ahn, Robert J. Full

All HMC Faculty Publications and Research

The individual muscles of a multiple muscle group at a given joint are often assumed to function synergistically to share the load during locomotion. We examined two leg extensors of a running cockroach to test the hypothesis that leg muscles within an anatomical muscle group necessarily manage (i.e. produce, store, transmit or absorb) energy similarly during running. Using electromyographic and video motion-analysis techniques, we determined that muscles 177c and 179 are both active during the first half of the stance period during muscle shortening. Using the in vivo strain and stimulation patterns determined during running, we measured muscle power output. …