Kinesiology Commons^™

Effects Of Instability On Core Muscle Activation In A Side Bridge, Erin E. Kishman

Masters Theses

Training the musculature of the core continues to be perceived as an essential component of conditioning and rehabilitation settings (11). A popular way to train the core is with the use of instability devices, such as Swiss ball or suspension trainer. However, there is limited research on the effects of these devices on core muscle activity. The purpose of this study was to examine core muscle activity during side bridge variations with and without instability devices (Floor, Swiss Ball, and TRX) through electromyography (EMG) of the rectus abdominis, external oblique, erector spinae, and latissimus dorsi. 39 participants performed three variations …

Motor Affordance For Grasping A Safety Handle, Doug W. Mcdannald

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

Observation of objects in our environment can potentiate movement, a fact reflected by increased activity in motor cortical networks when participants simply view a graspable object. This suggests that specific areas in the motor cortex play an important role in processing visual information to rapidly determine an appropriate action. The present study was conducted to test if visual access to a wall-mounted safety handle results in activation of motor cortical networks. We hypothesized that the hand area of the primary motor cortex would be facilitated shortly after visual access to a safety handle versus when no handle was visible. To …

Intraindividual Variability And Validity In Smart Apparel Muscle Activity Measurements During Exercise In Men, Jonathan Aquino, Jenevieve L. Roper

International Journal of Exercise Science

International Journal of Exercise Science 11(7): 516-525, 2018. The purpose of the study was to compare smart apparel (SA) muscle activity measurements to surface electromyography (sEMG) muscle activity measurements during exercise, and determine if any systematic bias of the apparel exists. Thirty-five male participants (Ages 23.1±2.92 yrs, height 178±0.09 cm, mass 81.14±10.59 kg, body fat percentage 15.4±4.79%) provided informed consent for participation. During two separate exercise sessions, participants performed three sets of 12 bodyweight squats and pushups in both SA and sEMG. Conditions (sEMG or SA) were randomly counterbalanced. During sEMG, sensors were placed at selected anatomical locations on the …

The Effect Of Treadmill Vs. Nustep Recumbent Cross Trainer On Gait And Lower Extremity Electromyography After Chronic Stroke, Nicholas Joseph Siekirk

Wayne State University Dissertations

Pilot Part 1: The purpose was to investigate the effect of a perceived exertion based cadence on lower extremity muscle activation, as measured by surface electromyography (EMG) on a recumbent cross trainer. The purpose of this investigation was to study the EMG activity of 12 lower extremity muscles during five different stepping protocols; perceived exertion based self-selected (SS) cadence with level 1 resistance (SSL1), SS cadence with level 8 resistance (SSL8), +20% SS cadence (SS+20), -20% SS cadence (SS-20), and at a set 80 steps per minute at resistance level 1 (80L1). In order to determine SS cadence each participant …

Muscle Activation Analysis With Kinematic Comparison Between Wind-Up And Stretch Pitching With Respect To The Upper And Lower Extremities, Megan M. Smidebush

Theses and Dissertations--Kinesiology and Health Promotion

Introduction: Baseball pitching is considered one of the most intense aspects within the game of baseball, as well as the most complicated dynamic throwing task in all of sports. The biomechanics of pitching have been heavily investigated in an attempt to identify optimal pitching mechanics in terms of pitching performance. Previous quantified upper body kinetics research has concluded that improved muscle strength is needed in attempting to achieve adequate upper body kinetics and efficient pitching performances. Therefore, it is the purpose of this research study to compare the lower extremity muscle and upper extremity muscle activation patterns and kinematic variables …

Muscle Synergy During A Single Leg Standing Test In Ambulatory Children With Cerebral Palsy, Brennan L. Smith

Theses and Dissertations--Kinesiology and Health Promotion

INTRODUCTION: Cerebral Palsy (CP) is a sensorimotor disorder characterized by dysfunctional motor coordination, balance problems, and loss of selective motor control. Motor coordination exhibited as co-contraction, has been subjectively quantified using gait analysis, but recent studies have begun to objectively analyze the amount of co-contraction by collecting electromyography (EMG) data. Center of pressure excursion (COPE) measurements collected during a single leg standing test (SLST) have shown to be more valid measurements of balance in populations with motor disabilities than a SLST alone. A recent study has correlated increased COPE velocity with a lower fall risk as determined by reported fall …

Effect Of Seat Tube Angle And Exercise Intensity On Muscle Activity Patterns In Cyclists, Will Duggan, Bernard Donne, Neil Fleming

International Journal of Exercise Science

International Journal of Exercise Science 10(8): 1145-1156, 2017. Previous studies have reported improved efficiency at steeper seat tube angle (STA) during ergometer cycling; however, neuromuscular mechanisms have yet to be fully determined. The current study investigated effects of STA on lower limb EMG activity at varying exercise intensities. Cyclists (n=11) were tested at 2 workloads; 160W and an individualised workload (IWL) equivalent to lactate threshold (T_Lac) minus 10%δ (derived from maximal incremental data), using 3 STA (70, 75 and 80°). Electromyographic data from Vastus Medialis (VM), Rectus Femoris (RF), Vastus Lateralis (VL) and Biceps Femoris (BF) were assessed. …

The Effects Of A Short-Term Endurance Training Program With Blood Flow Restriction Cuffs Versus Acsm Recommended Endurance Training On Arterial Compliance And Muscular Adaptations In Recreationally Active Males, Brittany N. Esparza

Theses and Dissertations

RESULTS: Significant time and group interaction found in cardiac ejection time (p<.05). Significant condition difference between blood flow restriction (BFR) and control for heart rate (HR) max (p=.05) and maximum oxygen consumption (VO2) (p<.05). Significant time difference found in pulse wave velocity femoral to distal (p<.05). Significant repetition main effect (p<.01) for root mean square (RMS) and median frequency (MDF) of Thorstensson. Significant time and group interaction in vastus lateralis of MDF (p<.01). Significant repetition main effect for RMS and MDF ratio (p<.01) Significant time and repetition interaction in vastus lateralis of RMS ratio (p<.03)

CONCLUSION: The BFR session showed improvement in both post HR max and post VO2 in comparison to the control group. This may have been caused by increased tolerance to pain/metabolic by-products for HR and increased efficiency at extracting oxygen for VO2

Neuromuscular And Arterial Compliance Responses To Different Resistance Training Frequencies And Protocols, Patrick Murphy

Theses and Dissertations

PURPOSE: The purpose of this study was to determine the impact of blood flow restriction and resistance training on arterial elasticity, EMG activity, and strength indices among sedentary to recreationally active females who completed 6 weeks of resistance training.

RESULTS: Significant time*condition interactions occurred in LE-1RM (p

CONCLUSION: The research group(s), 1–2 days/week with and without blood flow restriction, may increase training adaptations and responses parallel to the control group (3 days/week). There appears to be no differences in arterial compliance between groups.

Recovery Of Hip And Back Muscle Fatigue Following A Back Extension Endurance Test, Sharon Wang-Price, Mohammad Almadan, Carissa Stoddard, Dustin Moore

International Journal of Exercise Science

International Journal of Exercise Science 10(2): 213-224, 2017 Literature has not shown the minimum time required to recover from muscle fatigue after a prolonged trunk isometric contraction. The purpose of this study was to determine if the lumbar multifidus (LM) and gluteus maximus (GM) muscles would recover from fatigue after three different rest periods following performance of a back extension endurance test. Endurance time and electromyographic (EMG) activity of bilateral LM and GM muscles were collected from 12 healthy adults during a modified Biering-Sørensen test. On three separate visits, each participant performed two modified Biering-Sørensen tests, one before and one …

Differences In The Muscle Activity For Baseball Hitters Of Varying Skill, Ethan M. Stewart

Theses and Dissertations--Kinesiology and Health Promotion

INTRODUCTION: Muscle activity and timing of the swing phases may contribute to the differences we see in athletes at different skill levels. The purpose of this study is to analyze the differences between mean muscle activity, peak muscle active and time to peak muscle activity for select muscles in the lower extremity as well as the differences between start times for swing phases and bat velocity prior to impact for a skilled and recreational group. METHODS: Twelve healthy subjects were split into two groups based on competitive level and analyzed hitting off of a tee. RESULTS: No significant differences were …

Exercise-Induced Glycogen Reduction Increases Muscle Activity, Matthew S. Tenan, J. Troy Blackburn, Robert G. Mcmurray

International Journal of Exercise Science

International Journal of Exercise Science 9(3): 336-346, 2016. Intramuscular glycogen stores are an important energy source during extended bouts of strenuous exercise. A substantial reduction in glycogen could influence neural muscular drive and result in a decreasing quality of exercise performance and potentially increased injury rates. The aim of this study was to examine the effect of glycogen reduction on motor drive as determined by the surface electromyogram (EMG) amplitude and median frequency during a cycling graded exercise test. Eight trained cyclists performed a discontinuous cycling graded exercise test to exhaustion under both normal and glycogen reduced conditions. EMG …

Time Course Of Changes In Neuromuscular Parameters During Fatiguing High-Load And Low-Load Concentric Dynamic Constant External Resistance Leg Extension Muscle Actions, Cory M. Smith

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

The purpose of this study was to simultaneously assess electromyographic (EMG) and mechanomyographic (MMG) signals to examine the time course of changes in EMG amplitude, EMG frequency, MMG amplitude, and MMG frequency from the vastus lateralis (VL), vastus medialis (VM), and rectus femoris (RF) muscles during high-load (70%1 repetitions maximum; 1-RM) and low-load (30% 1-RM) concentric, dynamic constant external resistance (DCER) leg extension muscle actions to failure. Twelve men performed two randomized visits consisting of either 30 or 70% 1-RM DCER leg extension muscle actions to failure. Maximal voluntary isometric contractions (MVIC) and 1-RM measurements were performed before and after …

Electromyography Study Of Muscle Fatigue During Isometric Exercises In Swimmers And Non-Swimmers, Tiffany Aeling

Theses, Dissertations and Capstones

The use of electromyography (EMG) techniques offer strong evaluation of musculature fatigue during activity in different exercises. Studies show that EMG can be used to monitor fatigue patterns in muscles composing the upper extremities and thoracic areas of the human body by analyzing median frequency values. Advances in muscle fatigue research have been critical for improving rehabilitation programs for patients with musculoskeletal conditions. Despite these developments, many collegiate athletes are still at high risk for muscle injury on and off the playing field. Therefore, in order to help reduce injury numbers, it is important that current research focus on the …

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 …

Static Stretching And Preconditioning Exercise Augments Power Output In Recreational Athletes, Mark R. Mason

Theses and Dissertations--Kinesiology and Health Promotion

The purpose of this study was to determine the independent and combined effects of performing a preconditioning exercise and antagonist stretching on vertical jump (VJ) performance. Twenty club rugby players performed a VJ in four conditions: control condition, following static stretching, following a preconditioning exercise, and following the combined treatment of static stretching and a preconditioning exercise. Electromyographic (EMG) activity was measured in the gluteus maximus, vastus lateralis, gastrocnemius medialis, and tibialis anterior during the VJ trials. Repeated measures ANOVA were used to compare VJ and EMG outcomes across conditions. A Bonferroni correction was used to account for multiple post-hoc …

Neural Recovery Rates Of Knee Extensors Following A Resistance Exercise Protocol, Darren Michael Polk

LSU Master's Theses

Fatigue can manifest in the human body in a multitude of ways, one of these is neural-based fatigue. Neural-based fatigue occurs when the nerve fails to activate a muscle (Brooks et al., 2005). The purpose of this research is to investigate rates of neural recovery following a resistance exercise protocol. A pre-test consisting of a 5-second maximum voluntary isometric knee extension was performed. Next, each subject performed a resistance exercise protocol consisting of 5 sets of 10 repetitions of isokinetic knee extensions. Post-tests following the resistance exercise protocol consisted of 5-second maximum voluntary isometric knee extensions after 1, 5, 10, …

Relationship Between Metabolic By-Products And Nervous System Failure/Fatigue, Tyler Mitchell Farney

LSU Doctoral Dissertations

Fatigue has generally been defined as an acute impairment of exercise/sport performance that includes both an increase in the perceived effort necessary to exert a desired force or power output, and the inability to produce the desired force or power output. The majority of research to date looking at fatigue has focused upon substrate utilization, however, what is relatively unknown is the contribution the nervous system has upon fatigue. Therefore, the purpose of this dissertation was to investigate potential mechanisms that relate to neural fatigue. An additional purpose was to determine if there were any relationships between metabolic by-products and …

Individual Responses For Muscle Activation, Repetitions, And Volume During Three Sets To Failure Of High- (80% 1rm) Versus Low-Load (30% 1rm) Forearm Flexion Resistance Exercise, Nathaniel D. M. Jenkins, Terry J. Housh, Samuel L. Buckner, Haley C. Bergstrom, Kristen C. Cochrane, Cory M. Smith, Ethan C. Hill, Richard J. Schmidt, Joel T. Cramer

Kinesiology and Health Promotion Faculty Publications

This study compared electromyographic (EMG) amplitude, the number of repetitions completed, and exercise volume during three sets to failure of high- (80% 1RM) versus low-load (30% 1RM) forearm flexion resistance exercise on a subject-by-subject basis. Fifteen men were familiarized, completed forearm flexion 1RM testing. Forty-eight to 72 h later, the subjects completed three sets to failure of dumbbell forearm flexion resistance exercise with 80% (n = 8) or 30% (n = 7) 1RM. EMG amplitude was calculated for every repetition, and the number of repetitions performed and exercise volume were recorded. During sets 1, 2, and 3, one …

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 …

Lower Extremity Neuromechanics During A Forward-Side Jump Following Functional Fatigue In Patients With Ankle Instability, Hyun Kim

Theses and Dissertations

Ankle instability (AI) and fatigue impair neuromuscular control as well as dynamic joint stability of the lower extremity. No one has comprehensively examined the effects of AI and fatigue on neuromechanics of the lower extremity during a functional activity. Deficits associated with AI and fatigue could be additive in increasing the risk for injury in patients with AI. PURPOSE: To examine the interaction of AI and fatigue on lower extremity muscle activity, kinematic, and kinetic patterns during a forward-side jump. METHODS: 25 AI (23.3 ± 1.9 yrs, 176.5 ± 10.5 cm, 70.9 ± 11.4 kg), and 25 matched control subjects …

Investigating Single-Leg Landing Strategies And Movement Control Across Changes In Task Demands, Andrew D. Nordin

UNLV Theses, Dissertations, Professional Papers, and Capstones

Variability is an intrinsic characteristic of human movement, with hypothesized connections to neuromotor functioning and mechanisms of injury. The purpose of this study was to evaluate changes in movement variability among kinematic, kinetic, and electromyographic (EMG) variables following mechanical task demand manipulations during single-leg drop landings. Biomechanical outcome variables included 3 kinematic (sagittal, hip, knee, and ankle angles), 4 kinetic (sagittal hip, knee, ankle moments and vertical ground reaction force; GRFz), and 5 EMG variables (gluteus maximus, vastus medialis, biceps femoris, medial gastrocnemius, and tibialis anterior muscles). Mechanical task demands were altered using load and landing height manipulations, computed as …

The Effects Of Bag Style On Muscle Activity Of The Trapezius, Erector Spinae And Latissimus Dorsi During Walking In Female University Students, R. Hardie, R. Haskew, J. Harris, Gerwyn Hughes

Kinesiology (Formerly Exercise and Sport Science)

Back pain is common in adolescents which has been associated with carrying a bag. However, there is little research examining the effects of bag style in female adolescents. The aim of the study was to investigate the effects of different bag conditions on muscle activity of the trapezius, erector spinae and latissimus dorsi muscles in female university students during walking. Twelve female university students walked on a treadmill for 5 minutes at 1.1 m/s during five conditions; control, 1 strapped rucksack, 2 strapped rucksack, ipsilateral shoulder strap and contralateral shoulder strap, each containing 10% bodyweight. Electromyography for the trapezius, erector …

Acute Effects Of Dynamic Stretching On Flexibility And Agonist-Antagonist Muscle Activity, Lance T. Beisley

EWU Masters Thesis Collection

"Flexibility is an important determinant of health and important in sport performance. ADS and SPST are the methods most often used in training flexibility for sport. Although ADS appears to dominate SPST in measures of power and agility, the mechanisms are unclear. The purpose of this study was to delineate the effects of ADS on AROM and agonist-antagonist mean and peak EMG. The ADS protocol involved three sets of ten repetitions of leg kicks while in the supine position with the pelvis and contralateral limb fixed in extension. Participants moved the leg at the hip in a kicking motion to …

Active Versus Passive Control Of Arm Swing: Implication Of The Restriction Of Pelvis Rotation During Human Locomotion, Stephen Paul Canton

LSU Master's Theses

To date, it remains unclear how passive dynamics and active neural control contribute to arm swing during human locomotion. The passive hypothesis attributes arm swing to the passive transfer of energy from the legs to the arms via biomechanical linkages, while the active hypothesis states that arm swing is actively driven by muscles via neural mechanisms. The present study aims to investigate this phenomenon further by disrupting the biomechanical linkages, thereby directly challenging the passive hypothesis. Ten healthy individuals walked on a treadmill with and without an apparatus that constrained pelvis rotation at 3 different speeds (2 mph, 3 mph, …

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 …