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Tropomyosin-Based Effects Of Acidosis On Thin-Filament Regulation During Muscle Fatigue, Brent Scott Jul 2019

Tropomyosin-Based Effects Of Acidosis On Thin-Filament Regulation During Muscle Fatigue, Brent Scott

Masters Theses

Skeletal muscle fatigue is defined as a loss in the force/velocity generating capacity of a muscle. A portion of the loss in function is attributable to effects of acidosis (i.e. low pH) on the regulatory proteins, troponin and tropomyosin (Tm), which regulate the binding of myosin and actin in a calcium (Ca++) dependent manner. However, the relative role of troponin and Tm on myosin-actin function during acidosis is not clear, nor are the mechanisms underlying these effects. PURPOSE: To determine the role of Tm in the acidosis-induced depression of muscle function using isolated muscle proteins in an in ...


Volumetric Muscle Loss: The Role Of Physical Activity And Autologous Repair On Force Recovery And Signaling Pathways, Richard Perry May 2019

Volumetric Muscle Loss: The Role Of Physical Activity And Autologous Repair On Force Recovery And Signaling Pathways, Richard Perry

Theses and Dissertations

Volumetric muscle loss affects both military and civilian persons. The hallmark of this injury is incomplete muscle regeneration, excessive fibrosis, and chronic inflammatory signaling resulting in permanent functional loss. Since permanent functional loss drastically reduces quality of life, many studies have been conducted to improve force recovery. Current scientific literature considers a repair strategy of either devitalized scaffolds infused with growth factors or viable tissue plus activating factors to be the more promising interventions for optimal force recovery. PURPOSE The purpose of this study is to incorporate autologous repair and physical activity and observe the effects of muscle force recovery ...


Effects Of Resistance Training Frequency On Muscle Function Adaptations Using A Multiple-Joint Eccentric Training Model, Joshua Crane May 2019

Effects Of Resistance Training Frequency On Muscle Function Adaptations Using A Multiple-Joint Eccentric Training Model, Joshua Crane

All Graduate Plan B and other Reports

Eccentric resistance training has been shown to be beneficial for improving multiple performance and health metrics. However, recommendations on eccentric training frequency have not been established. PURPOSE: To investigate the effects of volume-matched resistance training frequency comparing one versus three training days per week of isokinetic multiple-joint eccentric training on strength and lower body function adaptations during a 4-week training period. METHODS: Thirty recreationally-trained men and women were randomly assigned to either a high frequency (HF), three times per week, or low frequency (LF), once per week, training group for four weeks. A motor-driven isokinetic eccentric dynamometer was used for ...


The Regulation Of Skeletal Muscle Fatigue During The Progression Of Cancer Cachexia, Brandon N. Vanderveen Apr 2019

The Regulation Of Skeletal Muscle Fatigue During The Progression Of Cancer Cachexia, Brandon N. Vanderveen

Theses and Dissertations

Cachexia is the unintentional loss of body weight secondary to chronic disease and is prevalent is roughly 50% of cancer patients. The loss of body weight and skeletal muscle mass is reduced functional capacity associated with reduced life quality. The etiology of cachexia is multimodal and complex; however, cachexia has been linked to several systemic (e.g. chronic inflammation, hypogonadism, anemia, insulin resistance) and behavioral (e.g. anorexia, inactivity) changes that can compound to accelerate muscle mass and body weight loss. While several inflammatory cytokines are associated with cachexia’s disease progression, our laboratory has established that Interleukin-6 (IL-6) is ...


Effect Of Trb3 On Skeletal Muscle Mass Regulation And Exercise-Induced Adaptation, Ran Hee Choi Apr 2019

Effect Of Trb3 On Skeletal Muscle Mass Regulation And Exercise-Induced Adaptation, Ran Hee Choi

Theses and Dissertations

Skeletal muscle, which composes over 40% of body mass, is responsible for daily locomotion and energy metabolism. It is a malleable tissue that can adapt its structure and function in response to internal and external environmental stimuli. Changing muscle mass and energy substrate utilization is a common skeletal muscle adaptation in response to various pathological conditions, including type 2 diabetes and obesity. Failure to maintain skeletal muscle mass and function has been correlated with increasing morbidity and mortality, as well as poor quality of life. Hence, maintenance of skeletal muscle integrity is a recommended strategy in achieving better quality of ...


The Effect Of Dehydration And Rehydration With A High Potassium Beverage On Muscular Strength In Collegiate Males, Mitchell Zaplatosch Jan 2018

The Effect Of Dehydration And Rehydration With A High Potassium Beverage On Muscular Strength In Collegiate Males, Mitchell Zaplatosch

Graduate Theses and Dissertations

Introduction: Dehydration has been shown to impact both health and aerobic exercise performance, with less research examining the impact of dehydration on muscular strength. Rapid weight loss via dehydration is a common practice in several weight class sports dealing with muscular strength and power. Exercisers may also unintentionally begin a resistance training session in a dehydrated state as a result of hot environmental conditions or failure to restore fluid balance following previous activity, possibly inhibiting performance. Most rehydration strategies have focused on the inclusion of sodium in a beverage to restore plasma volume, while less have considered the role of ...


Rna Sequencing In The Development Of Cancer-Cachexia, Thomas Allen Blackwell Aug 2017

Rna Sequencing In The Development Of Cancer-Cachexia, Thomas Allen Blackwell

Theses and Dissertations

Introduction: Cancer is a major public health problem in the U.S. and the world. In 2013 there were an estimated 1,660,290 new cases of cancer in the U.S. Cancer-Cachexia (CC) is a common effect of many cancers, and is directly responsible for 20-40% of cancer-related deaths. The mechanisms that control the development of CC are not well understood. Most investigations of CC focus on the post-cachectic state and do not examine the progression of the condition. The purpose of this study was to utilize RNA sequencing to analyze transcriptomic alterations throughout the progression of CC. Methods ...


Wheelchair Fatigue Reducer, Aaron Miller, Dennis Andre Norfleet May 2016

Wheelchair Fatigue Reducer, Aaron Miller, Dennis Andre Norfleet

Chancellor’s Honors Program Projects

No abstract provided.


The Effects Of Two Different Resistance Training Protocols With Similar Volume On Muscular Strength, Muscle Thickness, And Fat-Free Mass, Cory Worthey Mar 2016

The Effects Of Two Different Resistance Training Protocols With Similar Volume On Muscular Strength, Muscle Thickness, And Fat-Free Mass, Cory Worthey

Theses and Dissertations

The manipulation of exercise volume, intensity, and order is associated with producing different musculoskeletal changes. These resistance training program variables affect mechanical tension and metabolic stress associated with resistance training, therefore affecting strength and hypertrophic outcomes. PURPOSE: The purpose of this study was to examine the effects of two different volume-equated total body exercise protocols over 9 weeks using compound exercises on muscular strength, muscle thickness, and fat-free mass. METHODS: Eight well-trained men were randomly assigned to a hypertrophy-style protocol (HG) performing 3 sets of 10 repetitions with 90 seconds rest between sets (n = 4) or a strength-style protocol (SG ...


Electromyography Study Of Muscle Fatigue During Isometric Exercises In Swimmers And Non-Swimmers, Tiffany Aeling Jan 2016

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 ...


Lifestyle Contributors To Cardiovascular Disease Risk, Adam J. Berrones Jan 2016

Lifestyle Contributors To Cardiovascular Disease Risk, Adam J. Berrones

Theses and Dissertations--Kinesiology and Health Promotion

Aortic stiffness is an independent risk factor that has prognostic value regarding future cardiovascular disease (CVD) events such as myocardial infarction, strokes, and heart failure. Although death rates due to coronary heart disease have declined in recent years, the leading global killer remains CVD and prevalence is still high. Understanding lifestyle contributors associated with aortic stiffness would provide the public with insight into targeting key health-related behaviors.

The purpose of this observational study was to examine the association of physical activity, physical function, and dietary quality as independent factors contributing to aortic stiffness in apparently healthy middle aged men. Fifty-two ...


Maximal Motor Unit Discharge Rates Of The Medial And Lateral Gastrocnemeii Of Young Males, Mitchell T. Graham Sep 2014

Maximal Motor Unit Discharge Rates Of The Medial And Lateral Gastrocnemeii Of Young Males, Mitchell T. Graham

Electronic Thesis and Dissertation Repository

The triceps surae is composed of the mono-articular soleus and the bi-articular gastrocnemeii. Mean maximal motor unit discharge rates (MUDRs) reported for the soleus (~16Hz) are lower than other limb muscles tested (Dalton et al., 2009). Because of differences in fibre-type and functional anatomy it is important to determine maximal MUDRs in the two heads of gastrocnemeii, as compared with the soleus, to fully understand the interplay of these three muscles for plantar flexion. The purpose of the study was to record maximal MUDRs of the medial (MG) and lateral gastrocnemeii (LG) in 9 recreationally active, young men (age 24 ...


Comprehensive Analysis Of Abdominal Tendon Length:Muscle Length Ratios In Human And Rat Specimens, Alexander J. Stephen Aug 2014

Comprehensive Analysis Of Abdominal Tendon Length:Muscle Length Ratios In Human And Rat Specimens, Alexander J. Stephen

Electronic Thesis and Dissertation Repository

Introduction: This study measured and described the tendon to muscle length ratios (TMRs) of the external oblique (EO), internal oblique (IO), rectus abdominus (RA), and transverse abdominus (TrA) muscles in humans and rats. Methods: The abdominal muscles of human and rat specimens were dissected and the length of the muscle fibers from their posterior attachments to the lumbodorsal fascia or the rib cage, and the lengths of their tendons, were measured. The tendon length was divided by muscle fiber length to calculate the TMR. Results: The TMRs for the human EO, IO, and TrA muscles were significantly larger than the ...


Effects Of An In-Season Resistance Training Program On Lower Extremity Power Output In Collegiate Basketball Players, Kevin Lee King May 2014

Effects Of An In-Season Resistance Training Program On Lower Extremity Power Output In Collegiate Basketball Players, Kevin Lee King

Theses and Dissertations

The purpose of this study was to evaluate changes in muscle power performance in a horizontal (forward movement), vertical, and lateral directions in collegiate basketball players due to the presence of an in-season resistance training program (ISRTP). Four basketball teams were recruited for this study. Two women's basketball teams and two men's basketball teams participated with one team in each gender participating in an ISRTP and one team not participating in an ISRTP. Fifty-three collegiate basketball players (Females= 29, Males= 24) were successfully recruited for this project. Subjects were assessed for lower extremity muscle power and muscle strength ...


Recovery From Muscle Fatigue In Young And Older Adults: Implications For Physical Function, Stephen A. Foulis Sep 2013

Recovery From Muscle Fatigue In Young And Older Adults: Implications For Physical Function, Stephen A. Foulis

Open Access Dissertations

As adults age, skeletal muscles become smaller and weaker, which can ultimately lead to declines in physical function and disability. In general, older adults produce less isometric force and dynamic power than younger adults. The effects of this weakness are amplified following a series of muscle contractions that result in muscle fatigue. Since daily routines consist of repeated series of activity followed by rest, it is important to understand how muscle recovers from fatigue. In particular, muscle power has been shown to be related to physical function and balance. Thus, understanding the process of recovery from muscle fatigue will help ...


The Effect Of N-Acetylcysteine Supplementation On Recovery Of Strength Following Eccentric Muscle Injury, Ryan C. Luke Dec 2011

The Effect Of N-Acetylcysteine Supplementation On Recovery Of Strength Following Eccentric Muscle Injury, Ryan C. Luke

Kinesiology Dissertations

This study determined the effect of N-acetylcysteine (NAC) supplementation on recovery of strength following eccentric muscle injury. Female subjects (n = 21, age = 20.7 ± .10 yr, weight = 68.05 ± 10.3 kg, height = 1.69 ± .07 m) performed one bout of eccentric exercise involving the forearm flexor muscles. Subjects were given a placebo (food-grade cellulose; n = 10) or NAC supplement (10 mg·kg-1 bw·d-1; n = 11) for 7D prior to and 14D following the exercise bout. Maximal Voluntary Contraction (MVC) torque, muscle soreness, range of motion (ROM), and arm circumference were measured at pre-exercise, immediately post-exercise, and ...


Optimal Control Of Human Running, Ross Herbert Miller May 2011

Optimal Control Of Human Running, Ross Herbert Miller

Open Access Dissertations

Humans generally use two modes of locomotion as adults. At slow speeds we walk, and at fast speeds we run. To perform either gait, we use our muscles. The central questions in this dissertation were: (1) Why do humans run the way they do, and (2) How do the mechanical properties of muscle influence running performance? Optimal control simulations of running were generated using a bipedal forward dynamics model of the human musculoskeletal system. Simulations of running and sprinting were posed as two-point boundary value problems where the muscle excitation signals were optimized to maximize an optimality criterion. In the ...


Comparative Forelimb Muscle Function In Turtles: Tests Of Environmental Variation And Neuromotor Conservation, Angela Rivera May 2011

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 ...


Fiber Type-Specific Desmin Content In Human Single Muscle Fibers, Heidi Ghent Mar 2006

Fiber Type-Specific Desmin Content In Human Single Muscle Fibers, Heidi Ghent

Theses and Dissertations

Contractile and cytoskeletal protein concentrations have been shown to differ on the basis of fiber type in whole muscle homogenates. The purpose of this study was to compare the content of the intermediate filament protein, desmin, between type I and type IIa single muscle fibers from a mixed muscle in human subjects. Biopsies were taken from the vastus lateralis of six recreationally active males. Approximately 150 single muscle fibers were dissected from each sample and analyzed using SDS-PAGE to determine myosin heavy chain (MHC) composition. Following identification, muscle fibers were pooled into two groups (MHC I and MHC IIa). Desmin ...