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The Effects Of Acidosis On Calcium Dependent Binding Of A Single Crossbridge, Matthew Unger Oct 2019

The Effects Of Acidosis On Calcium Dependent Binding Of A Single Crossbridge, Matthew Unger

Masters Theses

Intracellular acidosis is a putative agent of skeletal muscle fatigue, in part, because acidosis depresses the calcium (Ca2+) sensitivity and force production of muscle (18, 50). However, the molecular mechanisms behind this depression in Ca2+ sensitivity and force production are unknown. This gap in knowledge poses a significant challenge in generating a complete understanding of the fatigue process. To close this gap, the ability of myosin to bind to a single actin filament was measured under acidic conditions, in a laser trap assay, with and without regulatory proteins. Decreasing pH from 7.4 to 6.5 reduced the ...


Analysis Of Connectivity In Emg Signals To Examine Neural Correlations In Muscular Activation Of Lower Leg Muscles For Postural Stability, Diana Mccrumb Oct 2019

Analysis Of Connectivity In Emg Signals To Examine Neural Correlations In Muscular Activation Of Lower Leg Muscles For Postural Stability, Diana Mccrumb

Masters Theses

In quiet standing the central nervous systems implements a pre-programmed ankle strategy of postural control to maintain upright balance and stability. This strategy is comprised of a synchronized common neural drive being delivered to synergistically grouped muscles. In this study connectivity between EMG signals of unilateral and bilateral homologous muscle pairs, of the lower legs, during various standing balance conditions was evaluated using magnitude squared coherence (MSC) and mutual information (MI). The leg muscles of interest were the tibialis anterior (TA), medial gastrocnemius (MG), and the soleus (S) of both legs. MSC is a linear measure of the phase relation ...


Does Acute Preprandial Exercise Modify Postprandial Inflammation After A High Fat Meal In Young And Older Adults?, William Wisseman Aug 2019

Does Acute Preprandial Exercise Modify Postprandial Inflammation After A High Fat Meal In Young And Older Adults?, William Wisseman

Masters Theses

A single high-fat meal (HFM) can increase systemic inflammation (postprandial inflammation; PPI) and may be attenuated by recent exercise. However, the effect of preprandial exercise on PPI in older adults (OA) is not clear. Purpose: To determine if preprandial exercise attenuates PPI in YA and OA. Methods: 12 YA (23.3±3.9 years n= 5 M/7 F) and 12 OA (67.7±6 years, n= 8 M/4 F) completed two HFM challenges in a randomized order. During HFM alone, participants abstained from exercise 48 hours prior to the HFM session (except for the exercise session) and adhered ...


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 ...


Development And Cross-Validation Of A Cadence-Based Metabolic Equation For Walking, Christopher C. Moore Jul 2019

Mechanisms And Mitigation Of Skeletal Muscle Fatigue In Single Fibers From Older Adults, Aurora Foster Jul 2019

Mechanisms And Mitigation Of Skeletal Muscle Fatigue In Single Fibers From Older Adults, Aurora Foster

Masters Theses

Skeletal muscle fatigue is the contraction-induced decline in whole muscle force or power, and can be greater in older versus young adults. Fatigue primarily results from increased metabolism elevating phosphate (Pi) and hydrogen (H+), which alters myosin-actin interactions; however, which steps of the myosin-actin cross-bridge cycle are changed and their reversibility are unclear. PURPOSE: This study sought to: 1) Examine the effects of elevated Pi and H+ on molecular and cellular function, and 2) Test the ability of deoxyadenosine triphosphate (dATP), an alternative energy to adenosine triphosphate (ATP), to reverse the contractile changes induced with high Pi ...


How Successful High School Boys Soccer Coaches Perceive And Develop Cultural Competency: A Grounded Theory Approach, Lauren Jefferson Apr 2019

How Successful High School Boys Soccer Coaches Perceive And Develop Cultural Competency: A Grounded Theory Approach, Lauren Jefferson

Masters Theses

The purpose of this study was to examine how high school athletics coaches conceptualize the knowledge, values, and skills of cultural competence, with specific attention to learning processes and influences. In order to serve the increasingly diverse U.S. student population equitably and to the full holistic potential of extracurricular programming, high school coaches must develop a greater comfort with and capacity for exercising cultural competency. A qualitative approach using a grounded theory was applied. Seven coaches and one athletic director were recruited by purposive sampling. The research suggests a process-oriented, chronological model of how experienced coaches begin to work ...


Waist Circumference And The Relation To Aerobic Exercise And Perception Of Illness In Adults With Type 2 Diabetes Mellitus, Bailey J. Huebner Jan 2019

Waist Circumference And The Relation To Aerobic Exercise And Perception Of Illness In Adults With Type 2 Diabetes Mellitus, Bailey J. Huebner

Masters Theses

The purpose of this study was to observe the relationship between waist circumference (WC), amount of aerobic exercise performed weekly and overall Health Belief Model (HBM) score in adults with diagnosed type 2 diabetes mellitus (T2DM). Members from a local Midwest adult fitness program (n = 5) who had been diagnosed T2DM participated in this study. Participants ranged in age from 70 to 80 years with an average age of 74 years. Four of the participants were female and one participant was male. The questions included in this study were 1 .) in those with diagnosed T2DM, was a low overall HBM ...


Application And Evaluation Of Lighthouse Technology For Precision Motion Capture, Soumitra Sitole Oct 2018

Application And Evaluation Of Lighthouse Technology For Precision Motion Capture, Soumitra Sitole

Masters Theses

This thesis presents the development towards a system that can capture and quantify motion for applications in biomechanical and medical fields demanding precision motion tracking using the lighthouse technology. Commercially known as SteamVR tracking, the lighthouse technology is a motion tracking system developed for virtual reality applications that makes use of patterned infrared light sources to highlight trackers (objects embedded with photodiodes) to obtain their pose or spatial position and orientation. Current motion capture systems such as the camera-based motion capture are expensive and not readily available outside of research labs. This thesis provides a case for low-cost motion capture ...


Circulating Microrna Following High Intensity Interval Cycling With And Without Post-Exercise Nutrient Consumption, Jeremy Via May 2018

Circulating Microrna Following High Intensity Interval Cycling With And Without Post-Exercise Nutrient Consumption, Jeremy Via

Masters Theses

Introduction: MicroRNA (miRNA) are small, non-coding RNA that act post-transcriptionally to regulate gene expression. miRNA levels are modulated by acute aerobic exercise, yet little is known about how miRNA levels may change in response to high-intensity interval exercise. Further, almost nothing is known about the impact of post-exercise nutrition (carbohydrate and/or protein) on miRNA levels. Thus, the purpose of this study is to examine the effects of high-intensity interval cycling and different post-exercise nutrients on ci-miRNA levels. Methods: Nine recreationally active males (age 21.9 ± 2.0yrs; VO2max 49.6 ± 4.0mL/kg/min) competed three trials, each ...


The Effects Of Two Different Sports Drinks On Rpe And Finishing Speed Of An Endurance Run In Highly Trained Distance Runners, Matthew J. Feldhake Jan 2018

The Effects Of Two Different Sports Drinks On Rpe And Finishing Speed Of An Endurance Run In Highly Trained Distance Runners, Matthew J. Feldhake

Masters Theses

The purpose of this study was to compare the effects of a protein-containing sport drink with a traditional non-protein sport drink has on ratings of perceived exertion (RPE) and finishing speed of an half marathon. Of the possible factors that would support including protein in a sport drink the primary one was its inhibitory effect on serotonin release in the brain. This could help attenuate perceived exertion, thus allowing individuals to compete at a higher level for longer durations (Davis, Alderson, & Welsh, 2000).

This study was conducted using nine members of the Eastern Illinois University Men's Cross Country team ...


Application Of The Actigraph Gt9x Imu For The Assessment Of Turning During Walking And Running, Robert Thomas Marcotte Aug 2017

Application Of The Actigraph Gt9x Imu For The Assessment Of Turning During Walking And Running, Robert Thomas Marcotte

Masters Theses

PURPOSE: The purpose of this study was to examine the use of the ActiGraph GT9X gyroscope and magnetometer for turn detection and quantifying turn degree during walking and running. METHODS: Participants (N=17) completed pivot trials, treadmill walking and running (3 to 6 mph) and different degrees of turns (i.e. 45°, 90°, 135°, and 180°) during over-ground walking and running. Pivot and walking and running activities were completed for 1-minute and 6-minutes per trial, respectively. Turn frequency was constant (10 turns/minute) across all overground walking and running trials. ActiGraph GT9X devices were placed on the left and right ...


A Magnetic Resonance Compatible Knee Extension Ergometer, Youssef Jaber Jul 2017

A Magnetic Resonance Compatible Knee Extension Ergometer, Youssef Jaber

Masters Theses

The product of this thesis aims to enable the study of the biochemical and physical dynamics of the lower limbs at high levels of muscle tension and fast contraction speeds. This is accomplished in part by a magnetic resonance (MR) compatible ergometer designed to apply a load as a torque of up to 420 Nm acting against knee extension at speeds as high as 4.7 rad/s. The system can also be adapted to apply the load as a force of up to 1200 N acting against full leg extension. The ergometer is designed to enable the use of ...


The Effect Of Menstrual Phase And Oral Contraceptive Steroids On Caffeine During Cycling Performance, Annette M. Lemanski May 2017

The Effect Of Menstrual Phase And Oral Contraceptive Steroids On Caffeine During Cycling Performance, Annette M. Lemanski

Masters Theses

PURPOSE: There is evidence that female sex hormones impact caffeine metabolism, with decreased CYP1A2 activity and diminished caffeine clearance in women with higher estrogen levels. Therefore, the objectives of this project were to determine the effects of oral contraceptives and menstrual cycle on the benefits of caffeine supplementation for cycling performance. METHODS: Sixteen recreationally trained female cyclists, oral contraceptive steroid (OCS) users (n=8, age = 21.4 ± 1.4 years, height = 168.4 ± 3.6 cm, weight = 63.6 ± 7.2kg, VO2max = 48.0 ± 4.0 ml/kg/min), and non-users (n=8, age = 20.9 ± 2.1 years ...


Impact Of Pre-Exercise Feedings With A Low Or High Glycemic Index On The Ergogenic Effects Of Carbohydrate Mouth-Rinsing During Cycling, Nikolai J. Hladick May 2017

Impact Of Pre-Exercise Feedings With A Low Or High Glycemic Index On The Ergogenic Effects Of Carbohydrate Mouth-Rinsing During Cycling, Nikolai J. Hladick

Masters Theses

Purpose: Carbohydrate (CHO) ingestion during exercise enhances performance in short endurance events (~ 1 hr) due to neural influences, as demonstrated by the efficacy of CHO mouth-rinsing during cycling. However, the magnitude of these neural effects may be blunted following pre-exercise CHO feedings. This study examined whether the glycemic index (GI) of a pre-exercise meal affected time-trial (TT) performance in cyclists using a CHO mouth-rinse during exercise. Methods: Eight cyclists (age: 24 ± 6 yr; VO2max: 61 ± 8 ml×kg-1×min-1) completed 4 exercise trials, consisting of 15 min of constant-load cycling followed by a simulated 30-km TT. Treatments ...


The Impact Of Freedson Bout Vs. Non-Freedson Bout Physical Activity On Metabolic Syndrome Risk In College Students, Valerie Olijar May 2017

The Impact Of Freedson Bout Vs. Non-Freedson Bout Physical Activity On Metabolic Syndrome Risk In College Students, Valerie Olijar

Masters Theses

Purpose The aim of this study is to examine moderate to vigorous physical activity in Freedson bouts compared to non-Freedson bouts and their association with Metabolic Syndrome risk factors in college students.

Methods 72 subjects aged 18-26 were recruited from James Madison University. Subjects height, weight, waist circumference, blood pressure, and body composition were assessed on visit 1. Blood pressure, fasted blood glucose, and lipid profile were assessed on visit 2. Subjects wore an Actigraph GT3X+ accelerometer, which measured physical activity and sleep for 7 days and nights. Univariate Pearson correlation analyses were performed to determine the relationship physical activity ...


The Effects Of Coffee Ingestion On The Acute Testosterone Response To Exercise, Taylor Landry May 2017

The Effects Of Coffee Ingestion On The Acute Testosterone Response To Exercise, Taylor Landry

Masters Theses

Abstract

This study investigated the effects of coffee ingestion (COF) on serum testosterone responses to exercise in recreationally weight-trained males. Subjects ingested either 12 ounces of 6mg/kg caffeinated coffee (COF), decaffeinated coffee (DEC), or water (PLA) one hour prior to exercise in a randomized, within-subject, crossover design. The exercise session consisted of 21 minutes of high intensity interval cycling (alternating intensities corresponding to two minutes at power outputs associated with 2.0 mmol/L lactate and 4.0 mmol/L lactate) followed by resistance exercise (7 exercises, 3 sets of 10 repetitions, 65% 1RM, 1-minute rest periods). Subjects also ...


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 May 2017

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 ...


Effects Of A Raised Surface On Lower Extremity Kinematics, Kinetics, And Muscle Activation During A Sidecut In Recreational Female Softball Players, Lauren Elizabeth Schroeder May 2017

Effects Of A Raised Surface On Lower Extremity Kinematics, Kinetics, And Muscle Activation During A Sidecut In Recreational Female Softball Players, Lauren Elizabeth Schroeder

Masters Theses

Noncontact anterior cruciate ligament (ACL) injury is a common sports-related injury. “High-risk” dynamic movements, such as a sidecut, have been associated with increasing the risk of noncontact ACL injury. Certain biomechanical abnormalities, specifically at the hip and knee, and neuromuscular abnormalities, such as unbalanced quadriceps-to-hamstrings activation ratios and certain activation patterns prior to initial contact and after initial contact, have also been associated with an increased likelihood of noncontact ACL injuries occurring. Approximately 78% of all NCAA Division I softball game-day injuries are classified as noncontact where there is no direct contact to a player. Internal derangement of the knee ...


Playground And Garden Physical Activity Levels In Young Children, Ashlyn Nicole Schwartz May 2017

Playground And Garden Physical Activity Levels In Young Children, Ashlyn Nicole Schwartz

Masters Theses

The purpose of this study was to determine the differences in time spent in physical activity (PA), as assessed by the amount of time spent in PA, vector magnitude (counts/15 sec.), MET values, and energy expenditure (kcal/min), between two outdoor environments (natural playground and garden) in preschool children. Participants were twenty-five children (4.4±0.7 years) enrolled in a university laboratory preschool. PA was assessed using an ActiGraph GT3X+ accelerometer that was worn on the right hip. Each child completed four randomly ordered conditions (30 min each), which included two bouts of unstructured PA on the natural ...


The Effects Of Limb Dominance On Cross-Education In A Four Week Resistance Training Program, Caitlin Wend Jan 2017

The Effects Of Limb Dominance On Cross-Education In A Four Week Resistance Training Program, Caitlin Wend

Masters Theses

Cross-education is known as the phenomenon of strength transfer from the trained side of the body to the untrained side of the body by unilateral resistance training. Research has shown that limb dominance has an effect on the amount of strength that is gained on the untrained side. Studies have found that there is a greater cross over effect in strength from the dominant side of the body to the non-dominant side of the body than vice versa. The present study examined this effect by taking 12 college females and splitting them into three groups: dominant training, non-dominant training, and ...


Exercise Is Medicine: The Exercise Habits And Attitudes Towards Exercise Counseling Of Medical Practitioners, Zoë Roberts Jan 2017

Exercise Is Medicine: The Exercise Habits And Attitudes Towards Exercise Counseling Of Medical Practitioners, Zoë Roberts

Masters Theses

The purpose of this research was to examine the exercise habits of practicing physicians, physician assistants (PA), and nurse practitioners (NP) in Illinois to better understand their attitudes towards counseling their patients on exercise, and to analyze the frequency that these health care providers incorporate exercise counseling into their practices. Current data has revealed the exercise habits of physicians and how it has influenced the physicians' exercise counseling behaviors. But PAs and NPs have not been included in research collectively as a medical team on the topic using exercise counseling and prescription for patient care and treatment. The research was ...


The Influence Of Different Pre-Exercise Routines On Sprint Performance, Rok Mravljak Jan 2017

The Influence Of Different Pre-Exercise Routines On Sprint Performance, Rok Mravljak

Masters Theses

Sprint performance can be enhanced by interventions for short-term (acute) purposes and/or long-term purposes. Acute neuromuscular responses are usually achieved by using different pre-exercise routines at the end of the warm-up period. Recently, there have been several studies examining the effects of various pre-exercise routines on sprint performance, yet there has not been a research study designed that compared the three most commonly used pre-exercise routines in professional and recreational sports (static stretching, dynamic stretching and foam-rolling). Therefore, this study investigated and compared the results of static stretching, dynamic stretching, self-myofascial release and the control group, in order to ...


Effects Of Synthetic Turf And Shockpads On Impact Attenuation Related Biomechanics During Drop Landing, Hang Qu Dec 2016

Effects Of Synthetic Turf And Shockpads On Impact Attenuation Related Biomechanics During Drop Landing, Hang Qu

Masters Theses

Synthetic turf has been widely utilized in sports since 1964. Discrepancies, however, in injury incidence on synthetic turf and natural grass have been reported throughout studies. Adding a shock pad under synthetic turf carpet is claimed to aid in energy absorption and decrease impact loading. Although some studies have conducted materials tests and compared mechanical characteristics of synthetic turf with different shock pads, no studies have examined biomechanical characteristics of impact related human movements on an infilled synthetic turf system with different underlying shock pads. The purpose of this research was to investigate effects of an infilled synthetic turf with ...


Effects Of Wider Step Width On Knee Biomechanics In Obese And Healthy-Weight Participants During Stair Ascent, Derek Scott Yocum Dec 2016

Effects Of Wider Step Width On Knee Biomechanics In Obese And Healthy-Weight Participants During Stair Ascent, Derek Scott Yocum

Masters Theses

An increased likelihood of developing obesity-related knee osteoarthritis may be associated with increased peak internal knee abduction moment. Increases in step width may act to reduce this moment. This study focused on how step width influenced the knee joint during stair ascent by healthy and obese participants. Participants ascended stairs while walking at their preferred speed and under one of two step width conditions – preferred and increased. Obese participants experienced greater mediolateral and vertical ground reaction forces (GRFs), as well as increased peak knee extensor moments and push-off peak internal knee adduction moments. The findings of this study indicate that ...


Mechanisms Of Slowed Foot Tap Speed In Older Adults, Erica L. Hartman Jul 2016

Mechanisms Of Slowed Foot Tap Speed In Older Adults, Erica L. Hartman

Masters Theses

Rapid repetitive tapping, like the Foot Tap Test (FTT), slows with age, but the underlying mechanisms are unknown. Purpose: 1. Test the hypotheses that greater performance variability, increased muscle coactivation, and slowed muscle contractile speeds are related to lower foot tap count (FTC) in older adults; 2. Examine the relationship between FTC and physical function in older adults, using the advanced SPPB-A. Methods: 18 (25.0±3.1years, 9F, mean±SD), and 28 (73.4±4.9, 14F) adults were recruited; the later were divided into Higher (HFO) and Lower (LFO) Functioning based on SPPB-A score. Participants performed 10s of ...


The Influence Of Time-Of-Day Consumption And Training Status On The Ergogenic Properties Of Caffeine, James C. Boyett May 2016

The Influence Of Time-Of-Day Consumption And Training Status On The Ergogenic Properties Of Caffeine, James C. Boyett

Masters Theses

Purpose: The objectives were to determine the effects of time-of-day consumption and training status on the benefits of caffeine supplementation for cycling performance and peak muscle strength. METHODS: Twenty untrained and trained subjects completed four trials consisting of isokinetic peak torque testing and 3-km time trials (TT). Subjects ingested either 6 mg/kg of caffeine or a placebo one hour prior to each trial. Treatments were: morning + placebo, morning + caffeine, evening + placebo, evening + caffeine. Magnitude based inferences were used to evaluate treatment differences. RESULTS: Caffeine (‘very likely’ and ‘likely’) improved 3-km TT performance in the morning and evening. 3-km TT ...


A Low-Carbohydrate Ketogenic Diet Combined With Six Weeks Of Crossfit Training Improves Body Composition And Performance, Rachel M. Gregory May 2016

A Low-Carbohydrate Ketogenic Diet Combined With Six Weeks Of Crossfit Training Improves Body Composition And Performance, Rachel M. Gregory

Masters Theses

A low-carbohydrate ketogenic diet (LCKD) is a popular approach to weight and fat loss. CrossFit is a high-intensity power training (HIPT) type exercise for all levels of age and fitness that has gained recognition as one of the fasting growing sports in America. No previous research has been found which examines body composition changes or performance in individuals consuming a LCKD and participating in CrossFit training. PURPOSE: The purpose of this research was to examine the effects of a 6-week LCKD and CrossFit program on body composition and performance. METHODS: Twenty-seven non-elite CrossFit subjects (mean ± SD age = 34.58 ± 9 ...


A 16-Week Run Sprint Interval Training Does Not Have An Effect On Cardiovascular Risk Measured By Framingham Risk Score On Prediabetic Women, Joan A. Mandelson May 2016

A 16-Week Run Sprint Interval Training Does Not Have An Effect On Cardiovascular Risk Measured By Framingham Risk Score On Prediabetic Women, Joan A. Mandelson

Masters Theses

The Framingham risk score (FRS) was developed to determine the likelihood of developing cardiovascular disease (CVD) in the next 10 years using an individual’s age, gender, total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), smoking habits, and systolic blood pressure (SBP). Run-sprint interval training (R-SIT) has shown improvements in various health and blood markers while reducing total exercise time. To date there has not been a study that examines the effects of R-SIT and moderate intensity training (MIT) on framingham risk. The purpose of this study was to determine if a reduction of the 10-year risk of CVD (determined ...


The Effect Of Sleep Restriction On Coagulation And Fibrinolysis After Heavy Exercise, Paul A. Roberson May 2016

The Effect Of Sleep Restriction On Coagulation And Fibrinolysis After Heavy Exercise, Paul A. Roberson

Masters Theses

Introduction: Research has shown exercise elicits a hemostatic response affecting coagulation and fibrinolysis. Furthermore, prior research has determined circadian fluctuations exist where clotting potential increases in the morning as a result of increased PAI-1 and decreased tPA which is further exacerbated by exercise. These circadian fluctuations and exercise responses have the potential to be accentuated by poor sleep. The purpose of this study is to determine the effects of sleep restriction on tPA activity, PAI-1 activity, and Factor VIII antigen activity (FVIII) while resting and after exercise.

Methods: 7 Subjects underwent two similar exercises sessions (EX). EX1 occurred in the ...