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Articles 1 - 30 of 88
Full-Text Articles in Medicine and Health Sciences
A Comparison Of Ground Reaction Forces And Muscle Activity Of The Tsunami Bar® Against A Rigid Barbell During Back Squat Phases, John Carver Middleton
A Comparison Of Ground Reaction Forces And Muscle Activity Of The Tsunami Bar® Against A Rigid Barbell During Back Squat Phases, John Carver Middleton
Theses and Dissertations
An Institutional Review Board (IRB)-approved study was conducted to investigate the effects of the Tsunami Bar® (TB), a flexible barbell, on ground reaction force (GRF) production and muscle activity in the quadricep, hamstring, and gluteal muscle groups during phases of the squat exercise and compare the effects to the effects to using a rigid barbell (RB). A two-by-two repeated measures Analysis of Variance (ANOVA) test was used to compare the results. Descriptive statistics showed significantly higher GRFs for the TB during the unweighting phase, significant differences in GRFs between speeds for each phase, significantly higher forces on average with the …
Measuring The Effects Of Pre-Exhaust Training Using Electromyography, Zephaniah S. Pratt
Measuring The Effects Of Pre-Exhaust Training Using Electromyography, Zephaniah S. Pratt
Undergraduate Theses, Professional Papers, and Capstone Artifacts
This review is an examination of pre-exhaust electromyography studies, their cumulative results, and a discussion of specific shortcomings they exhibit. It concludes with a discussion on improvements future studies in the field can incorporate. Specifically, this review addresses the lack of understanding in regards to the current primary uses of PE (pre-exhaust), and EMG’s (electromyography) drawbacks when used to measure PE effectiveness. Current practices of PE focus on advanced weight training athletes attempting to improve the stimulus to fatigue ratio of their lifting sessions, and reduce their risk of injury. Research thus far has mainly focused on cross sectional studies …
Hip Muscle Function In Individuals With Chronic Ankle Instability, Lindsay Carroll
Hip Muscle Function In Individuals With Chronic Ankle Instability, Lindsay Carroll
Electronic Theses and Dissertations
Purpose: Hip muscle function has been reported to be altered in individuals with chronic ankle instability (CAI). The purpose of this study was (1) to determine whether the single leg squat test (SLST) could be used to detect differences in proximal muscle activation between individuals with and without CAI and (2) to determine if there was a difference in maximum isometric body weight normalized torque output of the hip lateral rotators, extensors, and abductors between individuals with and without CAI.
Subjects: Forty-eight subjects (14 males, 34 females; median age = 22.00 years, interquartile range (IQR) = 1.00; median height = …
Therapeutic Intervention Or Rider Influence On The Electromyographic Activity And Kinematics Of Horses, Karen L. Shaw
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 …
The Effect Of An On Body Personal Lift Assist Device (Jaipur Belt) On Trunk Muscle Fatiguability During A Repetitive Lifting Task In Manual Material Handlers – A Non-Randomized Single-Group Trial., Betty Thomas
Kasturba Medical College, Mangalore Theses and Dissertations
No abstract provided.
Difference In Proximal Femur Loading Due To Muscle Activity During Partial Weight Bearing And Nwb Standing- A Cross-Sectional Study., Smital Kshirsagar
Difference In Proximal Femur Loading Due To Muscle Activity During Partial Weight Bearing And Nwb Standing- A Cross-Sectional Study., Smital Kshirsagar
Kasturba Medical College, Mangalore Theses and Dissertations
No abstract provided.
Muscle Fatigue Response Of Rotator Cuff Muscles In Sitting And Standing Postures, Lisanne Aranha
Muscle Fatigue Response Of Rotator Cuff Muscles In Sitting And Standing Postures, Lisanne Aranha
Kasturba Medical College, Mangalore Theses and Dissertations
No abstract provided.
Electromyographic Analysis Of Shoulder Girdle Muscles During Sitting Pivot Transfer In Individuals With Paraplegia, Suchita Sunder
Electromyographic Analysis Of Shoulder Girdle Muscles During Sitting Pivot Transfer In Individuals With Paraplegia, Suchita Sunder
Manipal College of Health Professions, Manipal Theses and Dissertations
No abstract provided.
Therapeutic Exercise Influences On Activity Of The Multifidus Muscles In Horses, Tena L. Ursini
Therapeutic Exercise Influences On Activity Of The Multifidus Muscles In Horses, Tena L. Ursini
Doctoral Dissertations
Back pain is a worldwide debilitating condition that affects humans and animals alike. Lower back pain in humans can be caused by a myriad of conditions, including idiopathic origin. Spinal stability is compromised during disease, and a lack of stability also contributes to pathologic spinal conditions. Regardless of species, the stability of the spine depends on bones, ligaments, tendons and muscles. Muscles provide the only active component that can counteract various loads applied to the body. There are several muscle groups that contribute to spinal mechanics. The erector spinae group are large superficial muscles the lie along each side of …
Lower Extremity Muscle Recruitment Pattern During Sit To Stand Transfer In Children With Cerebral Palsy As Compared To Typically Developing Children- A Cross Sectional Study., Kiran P. Nadgauda
Kasturba Medical College, Mangalore Theses and Dissertations
No abstract provided.
Ankle Muscle Activation And Mechanics During The Ebbet's Foot Drills, Quentin Adam Archuleta
Ankle Muscle Activation And Mechanics During The Ebbet's Foot Drills, Quentin Adam Archuleta
Theses, Dissertations and Capstones
Introduction: The ankle is a complex structure of three joints that allow multiplanar motion (Brockett & Chapman, 2016). Lateral ankle sprains (LAS) are the most common injury seen today in both the general and athletic populations and have a high recurrence rate. When left untreated or mistreated, it often leads to developing chronic ankle instability or osteoarthritis, which a lower quality of life. Dr. Russ Ebbets created a set of foot drills with the claim that they can strengthen the muscles of the lower leg, lessen lower leg aliments, and the chances of a severe ankle sprain (Ebbets, 2011a). …
Electromyographic And Mechanomyogrpahic Signal Changes With Fatigue In Adults, Rehana Koilpillai
Electromyographic And Mechanomyogrpahic Signal Changes With Fatigue In Adults, Rehana Koilpillai
Honors Undergraduate Theses
Surface electromyography (sEMG) and mechanomyography (MMG) are well-studied signals that can reveal information about the physiological behavior of muscles during contraction. The purpose of this study was to quantify, characterize, and analyze the electrical and mechanical muscle responses to submaximal, isometric contractions in the rectus femoris in adults. Previous studies have investigated the use of EMG to monitor muscle fatigue. However, more information appears to be needed about the use of MMG to measure muscle fatigue during submaximal isometric contraction in the rectus femoris. In this study, the utility of MMG as a measure of muscle fatigue or muscle state …
Examination Of Sex- And Intensity-Specific Fatigue During Bilateral Leg Extension Exercise, Taylor Kayln Dinyer
Examination Of Sex- And Intensity-Specific Fatigue During Bilateral Leg Extension Exercise, Taylor Kayln Dinyer
Theses and Dissertations--Kinesiology and Health Promotion
The purposes of this study were to: 1) examine sex-related differences in the performance of repetitions to failure below (CL-10%, CL-20%) and above (50%, 60%, 70%, and 80% 1RM) the critical load (CL) to make inferences regarding the mechanisms responsible for variability in the performance of repetitions to failure at varying loads; 2) examine the time course of neuromuscular and muscle oxygen saturation responses during the performance of repetitions to failure below and above the CL; 3) to make inferences regarding motor unit activation strategies used to maintain force during the completion of repetitions below and …
Assessment Of Intrinsic Hand Neuromuscular Physiology, Philemon Tsang
Assessment Of Intrinsic Hand Neuromuscular Physiology, Philemon Tsang
Electronic Thesis and Dissertation Repository
Alterations to the peripheral nervous system and neuromuscular physiology may impact hand function in a typical or clinical population, such as individuals with ulnar neuropathy. The mechanisms that influence these positive and negative changes are still not well understood. The three studies within my thesis aim to validate the reliability of decomposition-based quantitative electromyography (DQEMG) measurements and explore the changes in intrinsic hand neuromuscular physiology in a typical aging population and individuals recovering from a surgical intervention for severe ulnar neuropathy.
The purpose of the first study was to determine the test-retest reliability of near-fibre (NF) jiggle, a measure of …
Inter-Rater Reliability And Intra-Rater Reliability Of Synchronous Ultrasound Imaging And Electromyography Measure Of The Lumbopelvic-Hip Muscle Complex, Courtney Caputo
Inter-Rater Reliability And Intra-Rater Reliability Of Synchronous Ultrasound Imaging And Electromyography Measure Of The Lumbopelvic-Hip Muscle Complex, Courtney Caputo
Honors Undergraduate Theses
Objective: The purpose of this study was to determine inter-rater and intra-rater reliability of synchronous ultrasound imaging and electromyography measures of lumbopelvic-hip muscle activity performed by a novice and an experienced investigator in healthy individuals. Electromyography (EMG) has served as the gold standard for quantification of onset of muscle activation; however, ultrasound imaging can visualize muscle activity when collected simultaneously. Methods: A novice and experienced investigator collected a series of 3 ultrasound images at rest and 3 M-mode clips during contraction of each muscle while EMG electrodes collected muscle activity. Muscles collected included: external oblique, erector spinae, rectus abdominis, gluteus …
Effects Of Relative Inertial Load On Performance Measures And Quadriceps Electromyography During Flywheel Resistance Training Squats, Jason Todd Brantley Jr.
Effects Of Relative Inertial Load On Performance Measures And Quadriceps Electromyography During Flywheel Resistance Training Squats, Jason Todd Brantley Jr.
Theses and Dissertations--Kinesiology and Health Promotion
Flywheel resistance training (FRT) has become an increasingly popular modality for exercising due to its unique application of providing external resistance. Little is known about how changes in relative inertial loads affects performance and electromyography (EMG) activity. The purpose of this study was to examine how performance metrics and quadriceps EMG activity are affected by relative inertial load during FRT-based squats. Fifteen resistance trained individuals completed five sets of five repetitions of squats with varying relative inertial loads in random order. Peak Eccentric Power (PEP), Peak Concentric Power (PCP), average force, total work, and repetition time were measured. Surface level …
An Investigation Of The Biomechanics Of Kinesiology Tape, Jessa Ward
An Investigation Of The Biomechanics Of Kinesiology Tape, Jessa Ward
Graduate Theses - Biology & Biomedical Engineering
Kinesiology tape has grown in popularity since its widespread use at the 2012 and 2016 Olympic Games. Manufacturers of these colorful tapes have advertised biomechanical benefits for athletes, including pain relief and muscle support, without much quantitative evidence to support these claims. The purpose of this research study was to evaluate the biomechanical aspects of kinesiology tape and how it affects subjects’ muscle activity. This research study evaluated the muscle activity of subjects’ low back before and after tape application during targeted, bodyweight exercises. Each subject’s muscle activity, measured through electromyography (EMG), was normalized and assessed using nonparametric statistical techniques. …
Emg Analysis Of Latissimus Dorsi, Middle Trapezius, And Erector Spinae Muscle Activity During Spinal Rotation: A Pilot Study, Alyssa Wagner, Brandon Forister, Zachary Huot
Emg Analysis Of Latissimus Dorsi, Middle Trapezius, And Erector Spinae Muscle Activity During Spinal Rotation: A Pilot Study, Alyssa Wagner, Brandon Forister, Zachary Huot
Physical Therapy Scholarly Projects
Purpose/Hypothesis: Rotation of the spine is a common movement used to complete daily activities and participate in sports. As a contributing factor to back injuries, the performance of spinal rotation is an important consideration for the rehabilitation of current and prevention of future back injuries. Muscles involved in spinal rotation have been researched, though limited findings exist for one of the largest back muscles, the Latissimus Dorsi (LD). The LD muscle contributes to many movements of the trunk and limbs given its multiple attachment sites including the pelvis, ribs, scapula, and humerus. Influence of the LD on spinal rotation has …
Electromyographic (Emg) Activity Of The Gluteus Medius During Various Hip Exercises, Kalie Maiden, Mitchell Karbo, Taylor Doeden, Analise Richtsmeier
Electromyographic (Emg) Activity Of The Gluteus Medius During Various Hip Exercises, Kalie Maiden, Mitchell Karbo, Taylor Doeden, Analise Richtsmeier
Physical Therapy Scholarly Projects
Background and Purpose. The purpose of the study was to record and analyze muscle recruitment patterns of the gluteus medius and gluteus maximus muscles when performing a side lying abduction exercise requiring consistent force to roll a ball up and down the wall using the dominant lower extremity. Comparisons were made between the use of either a small, medium or large ball. The subjects performed a standing abduction exercises with theraband around both ankles as well.
Case Description. Fifteen subjects were recruited from the University of North Dakota Department of Physical Therapy to perform the four different types of exercises. …
The Influence Of Patellofemoral Pain On Muscle Coordination, Segment Coordination, And Segment Coordination Variability In Runners, Carl Jewell
Doctoral Dissertations
Management of patellofemoral pain syndrome (PFPS) remains a significant challenge in clinical practice and there is a need to understand the mechanisms for altered gait and muscular function which may lead to poor patient outcomes. The overall aim of the three studies in this dissertation was to determine if runners with current PFPS adapt their gait and muscle activation as a result of long-term, daily pain and/or in response to an acute pain flare and exertion during a moderate intensity 21-minute treadmill run compared to healthy controls. In addition, a resolved, asymptomatic PFPS group was included to investigate potential mechanisms …
Individuals With Recurrent Low Back Pain Exhibit Significant Changes Of Paraspinal Muscle Performance After Lumbar Multifidus Intramuscular Fine Wire Electrode Insertion, Anthony Duong, Vincent Dinglasan, Russell Totten
Individuals With Recurrent Low Back Pain Exhibit Significant Changes Of Paraspinal Muscle Performance After Lumbar Multifidus Intramuscular Fine Wire Electrode Insertion, Anthony Duong, Vincent Dinglasan, Russell Totten
UNLV Theses, Dissertations, Professional Papers, and Capstones
STUDY DESIGN: Case control study. BACKGROUND: Recurrent low back pain (RLBP) is associated with paraspinal muscle dysfunction. Intramuscular electromyography (EMG) is a common tool for studying activation of the deep lumbar paraspinal muscles such as multifidi muscles, but it is currently currently unclear how muscle performance and activation are affected by the pain and micro-injury associated with intramuscular fine-wire electrode (IFWE) insertion and how it interacts with the presence of RLBP. OBJECTIVES: The purpose of this study was to examine how IFWE insertion into the lumbar multifidus affects paraspinal muscle strength and endurance in subjects with and without RLBP. METHODS: …
Functional Anatomy Of Palmar Musculature, Colin W. Moore
Functional Anatomy Of Palmar Musculature, Colin W. Moore
Electronic Thesis and Dissertation Repository
The palmaris longus (PL) and palmaris brevis (PB) are upper limb muscles considered atavistic remnants of those found in animal species. Despite their use in surgical grafting and tendon transfer procedures, the functional role of the PL and PB have not been investigated comprehensively in vivo. Using a multi-modal experimental approach consisting of indwelling fine wire electromyography (EMG), ultrasonography and immunohistochemical muscle staining techniques, the function of the PL and PB in the hand was evaluated both in in vivo and in situ.
The purpose of Study 1 was to determine whether the PL provides synergistic contributions to …
Neuromuscular Responses To Exhaustive Bouts Of Sprint Running In Non-Steady Speed Trials, Brandon C. Gruver, Matthew W. Bundle
Neuromuscular Responses To Exhaustive Bouts Of Sprint Running In Non-Steady Speed Trials, Brandon C. Gruver, Matthew W. Bundle
Graduate Student Theses, Dissertations, & Professional Papers
No abstract provided.
Muscle Synergy During A Single Leg Standing Test In Ambulatory Children With Cerebral Palsy, Brennan L. Smith
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 …
Electromyographic Activity Of Hamstrings And Quadriceps Muscle During Jumping And Landing: Pilot Study, Jayla Greene, Brecca Wahlund, Jay Mittlieder, Adam Lutz
Electromyographic Activity Of Hamstrings And Quadriceps Muscle During Jumping And Landing: Pilot Study, Jayla Greene, Brecca Wahlund, Jay Mittlieder, Adam Lutz
Physical Therapy Scholarly Projects
Background and Purpose. The purpose of this pilot study was to see if there was a difference in amount of electromyographic (EMG) activity in the quadriceps (vastus medialis and vastus lateralis) compared to amount of EMG activity in the hamstrings (biceps femoris and semitendinosus) in active male and female subjects during vertical jumping and landing. In addition, we looked at the amount of knee flexion that occurred in the male and female subjects shortly after landing from a vertical jump.
Methods EMG activity was recorded using a Noraxon TeleMyo DTS telemetry unit with a sampling rate of 1 kHz. EMG …
Emg Analysis Of Latissimus Dorsi, Erector Spinae, And Middle Trapezius Muscle Activity During Spinal Rotation: A Pilot Study, Hunter Huberty, Jacob Klingbeil, Michael Miller, Michael Utt
Emg Analysis Of Latissimus Dorsi, Erector Spinae, And Middle Trapezius Muscle Activity During Spinal Rotation: A Pilot Study, Hunter Huberty, Jacob Klingbeil, Michael Miller, Michael Utt
Physical Therapy Scholarly Projects
Purpose/Hypothesis: Rotation of the spine is a common movement used for completing daily activities and participating in sports. As a contributing factor to back injuries, the performance of spine rotation is an important consideration for the rehabilitation and prevention of future back injury. Muscles involved in spine rotation have been researched, though limited findings exist for one of the largest back muscles: Latissimus Dorsi (LD). The LD muscle contributes to many movements of the trunk and limbs given its multiple attachment sites including the pelvis, scapula, ribs and humerus. Influence of the LD on spine rotation, however, has not …
The Effects Of A Reduced Force Aerial Bucket Control On Upper Extremity Muscular Demands As Assessed With Surface Electromyography, Casey D. Garces
The Effects Of A Reduced Force Aerial Bucket Control On Upper Extremity Muscular Demands As Assessed With Surface Electromyography, Casey D. Garces
Master's Theses (2009 -)
A common control for operating aerial bucket trucks for utility companies in North America is called a pistol grip control. Based upon many anecdotal reports of forearm muscle fatigue from workers using this control, Prof. Richard Marklin began an EPRI-sponsored study in 2016 using EMG to determine muscle fatigue of workers while they used the pistol grip. Muscle activity recorded by EMG is a measure of the magnitude of muscle force under controlled conditions. This study confirmed the reports of muscle fatigue in extensor digitorum communis (EDC) muscle in the right forearm. The next phase of the study was to …
Athos Wearable Technology: A Comparison Study, Sara Desmarais, Madeleine Giess
Athos Wearable Technology: A Comparison Study, Sara Desmarais, Madeleine Giess
Senior Theses
Technological advances permit the assessment of new variables, and over time miniaturize and make portable equipment that once was restricted research or clinical settings. Validation of the new equipment is essential before it can be used. This study compared Athos Wearable Technology to a standard form of electromyography (EMG). We hypothesized that Athos would produce a similar percent of MVIC data when compared to a standard EMG during a series of movements. Participants performed five movements, once while wearing the Athos pants, and once while wearing Noraxon Wireless EMG Electrodes on their vastus lateralis, vastus medialis, and biceps femoris. The …
Age-Related Reductions Of Motor Unit Discharge Rates In The Human Hamstrings, Eric A. Kirk
Age-Related Reductions Of Motor Unit Discharge Rates In The Human Hamstrings, Eric A. Kirk
Electronic Thesis and Dissertation Repository
Neuromuscular age-related differences of human limb muscles have been widely described with the notable exception of the hamstring muscles. The purpose was to assess contractile function and spinal motor neuron output expressed as motor unit discharge rates in the hamstrings of 11 young (26 ± 4 y) and 10 old (80 ± 5 y) men. Maximal voluntary isometric contractions (MVC), stimulated contractile properties and motor unit discharge rates from sub-maximal to MVC were recorded from the lateral (biceps femoris) and medial (semimembranosus-semitendinosus) posterior thigh. In the old men, knee extension and flexion at MVC were lower (P < 0.05) and voluntary activation as assessed by the twitch interpolation technique was reduced (P < 0.05) compared with the young. Electrically evoked twitches were lower in amplitude and increased in duration of old hamstrings (P < 0.05) compared with the young. At sub-maximal to maximal contraction intensities the old had lower motor unit discharge rates as compared to the young (P < 0.001). At MVC, mean motor unit discharge rates in the biceps femoris and semimembranosus-semitendinosus of old hamstrings were 15.6 ± 6.4 and 15.3 ± 5.9 Hz, as compared to 26.1 ± 10.1 and 27.9 ±7.8 Hz in the young, respectively (P < 0.001). To date, the hamstrings show the greatest age-related reductions in motor unit discharge rates of any major limb muscle. These findings, in relation to motor unit discharge rates from other flexors and extensors support that in ageing, greater reductions are associated with limb flexor muscles.
Electromyographic Activity Of Hamstrings And Quadriceps Muscles During Jumping And Landing: Pilot Study, Joseph Burckhard, Tyler Kemnitz, Mikaela Dick, Alexandria Sweeney
Electromyographic Activity Of Hamstrings And Quadriceps Muscles During Jumping And Landing: Pilot Study, Joseph Burckhard, Tyler Kemnitz, Mikaela Dick, Alexandria Sweeney
Physical Therapy Scholarly Projects
Background and Purpose. The purpose of this pilot study was to find if there was a difference in the activation and firing time of the quadriceps (vastus medialis and vastus lateralis) compared to activation times of the hamstrings (biceps femoris and semitendinosus) in active males and females.
Methods. Subjects consisted of two male and two female athletes in good physical condition with no previous knee pathologies. During each of the trials, the muscle activity of each muscle was recorded. The EMG activity recorded using a Noraxon TeleMy02400 G2 telemetry unit with a sampling rate of 1 kHz which …