Kinesiology Commons^™

Effect Of Metabolic Rate On Mitochondrial Efficiency During Exercise In Human Skeletal Muscle In Vivo, Muhammet Enes Erol

Masters Theses

Introduction: Recent evidence in isolated mitochondria and permeabilized muscle fibers in ex vivo using simultaneous measurements of O₂ consumption and ATP production suggest that mitochondrial efficiency provides an additional mechanism to fine-tune oxidative phosphorylation rate to ATP demand in skeletal muscle. However, in the absence of a direct measurement of both VO₂ and ATP synthesis from the same region of the contracting muscle, whether this mechanism plays a role in the skeletal muscle in vivo is still unknown. Purpose: Using a noninvasive approach combining phosphorus and proton magnetic resonance spectroscopy (³¹P/¹H-MRS), the present study …

Stretch Activation During Fatigue Improves Relative Force Production In Fast-Contracting Mouse Skeletal Muscle Fibers, Philip C. Woods

Masters Theses

Stretch activation (F_SA) is the delayed increase in fiber specific tension (force per cross-sectional area) following a rapid stretch and can improve muscle performance during repetitive cyclical contractions. Historically considered minimal in skeletal muscle, our recent work showed the ratio ofstretch- to calcium-activated specific tension (F_SA/F₀) increased from 10 to 40% with greater inorganic phosphate (Pi) levels in soleus muscle fibers (Straight et al., 2019). Given Pi increases with muscle fatigue, we hypothesize that F_SA helps maintain force generation during fatigue. To test this, F_SA, induced by a stretch of 0.5% …

Incorporating Excess Post-Exercise Oxygen Consumption Into Accelerometer Energy Expenditure Estimation Algorithms, Nicholas Remillard

Masters Theses

Accelerometers are objective monitors of physical activity (PA) that can be used to estimate energy expenditure (EE). Most accelerometer EE estimation equations are based on steady-state data and do not consider excess post-exercise oxygen consumption (EPOC) after exercise. PURPOSE: To quantify the error in accelerometer EE estimates due to EPOC after varying durations of high-intensity treadmill running. METHODS: Nine young, healthy, recreationally active males participated in three study visits. Visit 1 included a treadmill VO₂ peak test to determine the treadmill speed correlating to 80% VO₂ peak for visits 2 and 3. Visit 2 included a seated 20-min …

The Progress Of Power: A Narrative Review Of The Practical Progression Of Running Power Assessment And Application, Andrew David Fields

Masters Theses

Power has revolutionized endurance athletics. Power is a function of the amount of force produced in a certain amount of time. Utilized correctly, it can be an effective metric of effort during endurance activities. Cycling saw the first fruits of this metric in the 1980s and 1990s with Tour de France athletes and has continued to provide immense benefits to cyclists. Power when applied to running, however, has seen a much slower progression toward effective use. Various attempts in the 1970s and 80s to use calculations to express running power as a function of multiple different kinematic variables proved futile. …

Reproducibility Of Alkaline Inorganic Phosphate Quantification Using 31p-Magnetic Resonance Spectroscopy At 3t, Alexs A. Matias

Masters Theses

INTRODUCTION: The detection of a second inorganic phosphate (Pi) resonance, a possible marker of mitochondrial content in vivo, using phosphorus magnetic resonance spectroscopy (31P- MRS) at 3T is technically challenging, which may prevent its reproducible quantification. PURPOSE: To determine the reproducibility of resting alkaline inorganic phosphate (Pialk) measurement using 31P-MRS in human skeletal muscle at 3 tesla (T). METHODS: Resting 31P- MRS of the quadriceps muscles was acquired on two separate visits, within seven days, in 13 healthy, sedentary to moderately active young adults using a whole-body 3T MR system. Measurement variability related to coil position, shimming procedure, and spectral …

Accelerometer-Determined Physical Behavior Metrics And Their Associations With Sarcopenia Among Oldest-Old Adults, Eric M. Eberl

Masters Theses

INTRODUCTION: Sarcopenia is a loss of muscle function and muscle mass which frequently occurs among the oldest-old adult population (aged 85+ years). The analysis of accelerometer-determined physical behavior volumes and patterns of oldest-old adults might provide novel insights into the associations with sarcopenia and its components. METHODS: A total of 145 participants in the primary sample and 87 participants in the subsample with a mean age of 88.2 (2.5) years from the Health, Aging, and Body Composition study cohort provided cross-sectional data of handgrip strength, appendicular lean mass, gait speed, and accelerometry. Probable, confirmed, and severe sarcopenia were assessed based …

Link Between Muscle And Whole-Body Energetic Responses To Exercise, Christopher M.T. Hayden

Masters Theses

Substantial evidence exists regarding how skeletal muscles use energy and how this affects muscular performance. What remains unclear is how characteristics of muscle energetics affect whole-body energetics during daily living, and what effects this may have on mobility. The goal of this study was to determine the associations between muscle and whole-body energetics including the relationships between: 1) muscle PCr depletion (∆PCr) in response to light intensity isotonic contractions and the oxygen deficit at the onset of a 30-min treadmill walk (30MTW), and, 2) muscle oxidative capacity and excess post-exercise oxygen consumption (EPOC; 30MTW), respiratory exchange ratio (RER; 30MTW), and …

The Relationship Between Relative Muscular Strength And Joint Mobility In Firefighters, Samuel C. Nozicka

Masters Theses

Firefighters job requirements consist of running upstairs, climbing ladders, ceiling breach and pull, carrying equipment, forcible entry, dragging hoses, raising ladders, and rescue of patrons all while wearing heavy protective equipment that limits their mobility (Park et al., 2015). The purpose of this study was to examine the relationship between relative strength and mobility within the population of firefighters. The subjects were volunteers consisting of twelve male firefighter ranging in age from 25-52 with the mean age of 37.7 ± 7.7 years. Leighton Flexometer was used to measure joint range of motion (ROM) in different active movement patterns (Leighton, 1966). …

Flexibility: The Forgotten Component Of Fitness: Eccentric Exercise Vs. Static Stretching To Improve Flexibility, Zach Cox

Masters Theses

The purpose of this research is to assess the effects of eccentric exercise as well as static stretching on flexibility following a six-week training intervention. It also compared the effects to those of a static stretching program. The hypothesis is that eccentric training will show larger enhancements in flexibility in sagittal plane movements of the hips and knees in comparison to a static stretching program. Training sessions were done three days per week and had a 24-hour rest period minimum between them. The exercises for the eccentric group were as follows: standing hip extension, standing split, straight leg lowering, and …

Strategies And Characteristics Of Young African American Women Who Maintain Physical Activity, Chloe Jones

Masters Theses

African American (AA) women have a disproportionately higher prevalence of obesity and physical inactivity compared to their gender and racial counterparts. Young AA women experience the largest increases in weight gain between 20-30 years of age, yet are underrepresented in current literature surrounding leisure-time physical activity (LTPA) promotion. Examining young AA women who successfully maintain LTPA participation may provide insight into their methods for doing so. The purpose of this study was to explore strategies used by active young AA women that support their LTPA maintenance, and identify various characteristics of these women.

A multimethod approach (qualitative and quantitative) was …

Impact Of Parity On Gait Biomechanics, Bekah P. Stein

Masters Theses

Background: Symptomatic knee osteoarthritis (OA) is an incurable condition that affects nearly 50% of adults, and women are twice as likely as men to develop OA. Throughout pregnancy, women experience large changes in morphology and gait mechanics, as well as changes in joint loading. It is possible these adaptations could cause lasting changes postpartum, which may potentially contribute to initiation of OA, thereby increasing the overall risk of OA for women.

Purpose: This exploratory study looked to identify differences between lower limb gait mechanics of healthy nulliparous women and healthy parous women.

Methods: 28 healthy female participants (14 parous, 14 …

Cadence As An Indicator Of The Walk-To-Run Transition, Colleen Chase

Masters Theses

Humans naturally select a point at which to transition from walking to running when gradually increasing locomotor speed. This point is known as the walk-to-run transition (WRT). The WRT is traditionally expressed in terms of speed and is known to occur within a close range of 2.1 m/s, which is an accepted heuristic (i.e., empirically based, rounded) threshold value. Very little research exists defining the WRT in terms of cadence (steps/min) despite the fact that spatial temporal aspects of gait underlying the WRT include this parameter. Preliminary evidence suggests that the WRT may be associated with a cadence of 140 …

A Comparison Of Vertical Ground Reaction Forces In Single-Leg Jump Take-Offs And Double-Leg Jump Take-Offs In Indoor Collegiate Volleyball Players, Margaret Elisabeth Latchford, Maggie Mcdermott, Austin Deshner, Moroni De Moors, Will W. Peveler

Masters Theses

The purpose of this study was to determine if differences in vertical ground reaction forces (vGRFs) exist between single-leg take-off approaches (SL) and double-leg take-off approaches (DL) and if sex or positional differences existed in vGRFs in SL- or DL-style approaches. It was hypothesized that DL jumps would generate greater vGRFs, males would generate greater vGRFs in both styles, and middle blockers would have higher SL vGRFs while pin hitters would have higher DL vGRFs. Nine collegiate volleyball players (4 female; 5 male) (age: 20.44 ± 1.42 years; height: 186.02 ± 6.44 cm; body mass: 78.21 ± 10.63kg; body fat: …

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 frequency …

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 …

Postactivation Potentiation Effects From Maximal Isometric Contractions Performed At Different Hip Joint Angles, Kyle Derosia

Masters Theses

The purpose of this study was to investigate the differences in vertical ground reaction force (VGRF) production and myoelectric activity after performing maximal isometric contractions at different hip joint angles. 10 healthy, experienced participants reported to the lab on two separate occasions where they performed 3 power cleans at baseline, then 4 maximal isometric deadlifts at either ~50° hip flexion angle (Max) or ~90° hip flexion angle (Min). Following the isometric deadlifts, another 3 power clean trials at 70% 1 repetition maximum were performed and used as a post-test. The isometric deadlifts served as the conditioning contraction (CC) to induce …

Effect Of Caffeine Supplementation On Vertical Jump Performance, Heart Rate Variability, And Electromyography, Collin T. Garner

Masters Theses

Research into caffeine’s ability to improve anaerobic performance is inconclusive. Eleven anaerobically trained individuals (mean age: 23.45 ± 1.51 years) participated in this study. Assessments of resting heart rate variability (HRV), exercise heart rate variability, surface electromyography (sEMG), static vertical jump (SJ), and countermovement vertical jump (CMJ) were conducted before and after administration of placebo and caffeinated treatments. Three trials of each vertical jump technique were performed before and after treatment administration. A 60-minute absorption period was utilized for absorption of the treatment following its ingestion. All participants performed testing on two separate occasions, once under the placebo condition and …

Relationship Between One Repetition Maximum Parallel Squat And Jump Squat Peak Power, Corey Klitzke

Masters Theses

Jump squats are a simple exercise that can be used to train lower body power. Unlike many other methods of power training, jump squats do not require any specialized equipment (platforms, bumper plates, etc.). Jump squats can be used when other forms of power training are not available or are not allowed. In order to most efficiently train power, the intensity must balance force and velocity. The purpose of this study was to find the intensity that yields the peak power output of a jump squat. 12 participants (9 males, 3 female) participated in the study. Each participant completed a …

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

Masters Theses

The ACSM Metabolic Equation is a widely recognized equation for predicting metabolic intensity from walking speed. However, an equation that uses an observable metric (i.e., cadence [steps/min]), accounts for individual characteristics, and is validated across walking conditions may enable more accessible and accurate predictions of walking intensity. PURPOSE: To develop metabolic equations that predict metabolic intensity (oxygen consumption; mL/kg/min) from cadence using a large treadmill walking dataset (Study One) and cross-validate these equations during overground unconstrained and cadence-constrained walking conditions (Study Two). METHODS: In Study One, 193 adults (21-81 years) completed treadmill walking bouts while oxygen consumption was measured with …

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 (P_i) 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 P_i 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 …

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 …

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 …

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 …

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

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 hips, wrists, and …

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 magnetic resonance …

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 playground and two bouts of …

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 analyze kinematic and …

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 …