Kinesiology Commons^™

The Role Of Osteocyte Estrogen Receptor Beta (Erβ) In Regulating The Skeletal Response To Mechanical Loading, Julia P. Townsend, Russell P. Main

The Summer Undergraduate Research Fellowship (SURF) Symposium

Estrogen’s biological functions are mediated by estrogen binding to estrogen receptors (ER). Understanding what role both ERα and ERβ have in bone maintenance and formation can contribute to possible treatment of osteoporosis. This study examined osteocyte specific deletion of ERβ in mice. The cross of ERβ-floxed mice with DMP1-8kb-Cre mice provided both experimental knockout mice as well as littermate control mice. At 24 weeks of age the left tibiae of all mice were mechanically loaded five days per week for two weeks to induce bone formation. Analysis of cortical bone was conducted using microcomputed tomography (microCT) to measure load-induced changes …

Effects Of Aging On The Relationship Between Cognitive Demand And Step Variability During Dual-Task Walking, Leslie M. Decker, Fabien Cignetti, Nathaniel Hunt, Jane F. Potter, Nicholas Stergiou, Stephanie A. Studenski

Journal Articles

A U-shaped relationship between cognitive demand and gait control may exist in dual-task situations, reflecting opposing effects of external focus of attention and attentional resource competition. The purpose of the study was twofold: to examine whether gait control, as evaluated from step-to-step variability, is related to cognitive task difficulty in a U-shaped manner and to determine whether age modifies this relationship. Young and older adults walked on a treadmill without attentional requirement and while performing a dichotic listening task under three attention conditions: non-forced (NF), forced-right (FR), and forced-left (FL). The conditions increased in their attentional demand and requirement for …

Increasing Nonsedentary Behaviors In University Students Using Text Messages: Randomized Controlled Trial, Emma Cotten, Harry Prapavessis

Kinesiology Publications

BACKGROUND: Sedentary behavior (SB) has been linked to many health problems such as type 2 diabetes and heart disease. Increasing the length and frequency of breaks from sitting and increasing the time spent standing and engaged in light and moderate physical activity are ways to decrease SB. Text message-based interventions have succeeded in aiding smoking cessation and increase both physical activity and healthy eating, but they have not been shown to reduce SB.

OBJECTIVE: The primary purpose of this pilot study was to determine the effectiveness of a text message-based intervention in increasing nonsedentary behaviors in university students. A secondary …

Relationship Between Body Composition, Fitness, And Eating Behaviors And Markers Of Metabolic Suppression In Exercising Men, Mikayla K. Locke, Karsten Koehler

UCARE: Research Products

Introduction: Chronic dieting can result in characteristic metabolic adaptations such as a suppression of resting metabolic rate (RMR). Previous research has focused on health outcomes related to metabolic suppression in female athletes, which include impaired menstrual and bone health. The study purpose was to assess the relationship between metabolic suppression and body composition, fitness, and eating behavior traits in exercising men.

Approach: Cross-sectional study comparing exercising men who display evidence of metabolic suppression (MS) and a control group (Con). RMR was used as a surrogate marker of metabolic suppression.

Results and Discussion: When compared to Con, MS …

Household, Psychosocial, And Individual-Level Factors Associated With Fruit, Vegetable, And Fiber Intake Among Low-Income Urban African American Youth, Angela Trude, Anna Kharmats, Kristen Hurley, Elizabeth Steeves, Sameera A. Talegawkar, Joel Gittelson

Exercise and Nutrition Sciences Faculty Publications

Background

Childhood obesity, one of the greatest challenges to public health, disproportionately affects low-income urban minority populations. Fruits and vegetables (FV) are nutrient dense foods that may be inversely associated with excessive weight gain. We aimed to identify the individual characteristic, psychosocial, and household factors influencing FV and fiber consumption in low-income African-American (AA) youth in Baltimore, MD.

Methods

Cross-sectional analysis of data collected from 285 low-income AA caregiver-youth (age range: 10–14 y) dyads participating in the baseline evaluation of the B’More Healthy Communities for Kids obesity prevention trial. The Kid's Block FFQ was used to estimate daily intakes of …

Observing Renal Responses To Endurance Cycling In The Heat, Cody Smith

Graduate Theses and Dissertations

AIM: To observe the effects of endurance cycling in the heat on renal function, and determine if the extent of impairment is related to hydration. METHODS: 40 cyclists (34 male, 6 female, 52 ± 9 y, 21.7 ± 6.5 % body fat) completed an endurance cycling event (5.7 ± 1.2 hours) in the heat (33.2 ± 5.0ºC, 38.4 ± 10.7% RH). Body mass was assessed to determine net fluid loss, muscle damage in the legs was assessed with a pain scale, a urine sample was collected to analyze hydration status, and a blood sample was drawn. All measurements were taken …

Levels Of Confidence In Schmieding Center In-Home Caregiving Training, Morena L. Valdizon

Health, Human Performance and Recreation Undergraduate Honors Theses

Abstract

The Schmieding Center for Senior Health and Education offers a unique approach and program designed to teach their students how to care for an older adult in the home. The purpose of this study was to determine the effectiveness of the in-home assistant course on the participant’s confidence levels. It was hypothesized that the confidence levels of the students that enrolled in the in-home assistant training course would increase with the completion of the 40-hour course and that demographic factors such as gender, age, and economic background would impact the levels of confidence. This study was conducted by the …

The Relationship Between Strength, Power, And Sprint Acceleration In Division I Men’S Soccer Players, Christopher Bellon

Electronic Theses and Dissertations

The purposes of this dissertation were three-fold. The first was to identify the approximate distances characterizing early-, mid-, and late-acceleration in a population of Division I men’s collegiate soccer players. The secondary purpose was to investigate the relationships between various strength-power variables and key sprint characteristics during early-, mid-, and late-acceleration in a population of Division I men’s soccer players. The final purpose of this dissertation was to compare the spatiotemporal characteristics of “strong” versus “weak” and “more powerful” versus “less powerful” Division I men’s soccer players during early-, mid-, and late- acceleration. The following are the major findings of …

Positional And Match Action Profiles Of Elite Women’S Field Hockey Players In Relationship To The 2015 Fih Rule Changes, Heather A. Abbott

Electronic Theses and Dissertations

The objective of this dissertation was to examine the action profiles of elite field hockey players in relationship to the 2015 FIH rule change. The following are major findings of the dissertation: The following are major findings of the dissertation: Study 1 – Relative action profiles before the rule change revealed that defenders work at a lower meter per minute (m/min) when compared with all other positions, and that forwards, midfielders, and screens perform similar m/min during a game. Examination of pre rule change difference from the 1st to the 2nd half play showed that elite level field hockey players …

Relationship Between Lower Body Strength, Countermovement Jump Height, And Optimal Drop Jump Drop Height, Cameron V. Griggs

Electronic Theses and Dissertations

The purpose of this study was to understand the relationship between back squat one-repetition maximum relative to body mass (1RMrel), countermovement jump height (CMJH), and optimal drop height in drop jump (DHopt). Fifteen male participants with various sport backgrounds and training experience completed a one repetition maximum (1RM) back squat, maximum countermovement jump (CMJ), and drop jumps (DJ) from incrementally increasing drop heights to determine which drop height elicited the greatest jump height. The DHopt testing protocol was unique in that smaller increments were used to determine DHopt compared to what has been reported in literature previously. Pearson correlation coefficients …

Muscle Activity And Power Output Between Stationary And Outdoor Cycling, Jared Joerger

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study is to compare lower extremity muscle activity and power output during cycling outdoors overground and cycling on a stationary bike trainer at different self-perceived intensity levels. Recreational and competitive cyclists and triathletes, eight male (48.6±8.7 years, 178.9±7.8 cm, 87.1±8.3kg) and three female (40.3±6.8 years, 158±1 cm, 59.6±9.3 kg), signed institutionally approved informed consents and participated in this study. Power data were collected using power instrumented bicycle pedals (PowerTap, Madison, WI) attached to the cyclist’s bicycle. Muscle activity was recorded using wireless electromyography (Delsys, Inc., Natick, MA) sampling at 1926Hz. Participants were tested for maximum voluntary …

Seasonal Perceived Training Load In Ncaa Di Men’S Soccer: Is There A Dose-Response Relationship?, Andrew A. Pustina

Electronic Theses and Dissertations

The purpose of this dissertation was to determine if a there was a dose-response relationship across an NCAA Division I men’s soccer season. Specifically, this dissertation serves to: 1.) assess the validity of duration measurements that have previously been used to calculate session RPE during competitive matches, 2.) determine the degree and magnitude of change in intermittent endurance performance across a season and to observe how change in endurance relates with training load, 3.) determine the degree and magnitude of change in strength and explosiveness across a season, and to see how these strength changes relate to training load. 1.) …

A Comparison Of Cervical And Trunk Musculoskeletal Characteristics Between Female And Male Army Helicopter Pilots, Takashi Nagai, Karen A. Keenan, John P. Abt, Timothy C. Sell, Brian W. Smalley, Michael D. Wirt, Scott M. Lephart

International Journal of Aviation, Aeronautics, and Aerospace

Introduction: Neck pain (NP) and low back pain (LBP) are prevalent among military helicopter pilots. Although there have been few studies on sex differences in the NP/LBP prevalence in this population, females are shown to be at a greater risk of NP/LBP in civilian studies. This disparity may be due to musculoskeletal characteristics differences that predispose females for NP/LBP. The purpose of this study was to compare cervical and trunk musculoskeletal characteristics between male and female pilots. Methods: A total of 8 female pilots (Age: 27.6 ± 4.2yrs, HT: 166.1 ± 7.7cm, WT: 67.9 ± 10.6kg) were tested, and they …

The Acute Effects Of Different Foam Rolling Timing Durations On Hamstring Flexibility, Chloe Marie Kipnis

UNLV Theses, Dissertations, Professional Papers, and Capstones

The use of a foam roller is growing in popularity as a part of a warm-up in order to prepare for activity. The current research, however, lacks an accepted timing duration for how long an athlete should foam roll prior to activity in order to increase range of motion (ROM). In order to guide clinical practice, it is necessary to establish a standard for how long an athlete should foam roll a muscle group with the goal to increase ROM. Therefore, the purpose of this study was to compare hamstring flexibility changes following a single foam rolling bout, performed for …

The Effect Of Moderate Consumption Of Non-Nutritive Sweeteners On Glucose Tolerance And Body Composition In Rats, Ashley Power Tovar

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Effect of Moderate Consumption Of Non-Nutritive Sweeteners On Glucose Tolerance And Body Composition In Rats

by Ashley Tovar

John C. Young, Ph.D., Examination Committee Chair Professor, Kinesiology and Nutrition Sciences University of Nevada, Las Vegas

Introduction: A comorbidity often seen with obesity is the development of impaired glucose tolerance. Abnormalities in the ability to metabolize glucose can lead to increased risk of developing pre-diabetes and if continued, diabetes mellitus type 2. To combat the effects of excess energy intake on obesity and glucose intolerance, low- energy and non-nutritive sweeteners have been introduced as a replacement for traditional sucrose and …

Effect Of Hydration Status On Thermoregulatory Responses In Non-Obese And Obese Males, Matthew Tucker

Graduate Theses and Dissertations

During heat stress the human body thermoregulates via cutaneous vasodilation and sweating. Hypohydration can impair thermoregulatory responses that stem from the central nervous system (CNS), but it is unknown if impairments also occur post-synaptically in the microcirculation. Moreover, obese individuals may have impaired thermoregulation, possibly due to microvascular dysfunction. Purpose: The purpose of these studies was two-fold: 1) to determine if obese (OB) individuals exhibit impairments in thermoregulatory responses during exercise heat-stress (centrally-mediated) and intradermal infusion of vasoactive substances (peripherally-mediated) versus non-obese (N-OB), and 2) to determine if hypohydration subsequently affects these thermoregulatory responses differently between groups. Methods: Twenty-one healthy, …

Mental Toughness, Grit, And Motivational Differences In Single-Sport And Multi-Sport Athletes, Cole Justin Shewmake

Graduate Theses and Dissertations

Whether it is at work, school or sports, mental toughness (MT), grit and motivation are essential to accomplishing goals. Sports can be an integral platform for developing MT, grit, and factors that increase motivation levels, and it is during childhood and adolescence that these characteristics may develop. All of this could prove beneficial into adulthood. Therefore, the purpose of this study was to examine MT, grit and motivational orientations of single-sport and multi-sport athletes at different levels of competition. Considering MT, a 2 x 2 ANOVA indicated no significant interaction effect between athlete type and competition level, F(1, 387) = …

The Influence Of Strength-Training Exercises On The Functional Fitness In Older Adults, Susie Engle

Graduate Theses and Dissertations

The purpose of this study was to examine the influence of strength-training exercises on the functional fitness in older adults. The original convenience sample consisted of 658 participants who attended group strength-training classes offered through the Cooperative Extension Service. The Senior Fitness Test was used to assess baseline fitness levels at the beginning and end of the 12-week strength-training program. Data was collected from 2008 to 2015. Of the 658 participants, 110 were aged 60 to 94 and presented posttest scores occurring approximately 12 weeks after pretest dates. Of the 110 subjects, 99 were female and 11 were male. The …

Examining The Effects Of Body Weight Support And Speed On Physiological Measures And Lower Leg Muscular Activity, Michael Thomas Soucy

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to determine if body weight support or speed influences specific physiological and biomechanical parameters while running at a preferred pace, or variations of preferred pace. Nine participants (age: 28.56 ± 7.88 years, height: 1.68 ± 0.08 cm, mass: 65.70 ± 7.64 kg) who were running a minimum of 10 miles per week (14.67 ± 4.92 miles) were recruited for participation. Participants were asked to sign an institutionally approved informed consent form upon arrival to the lab. After determining preferred running speed at each body weight support condition (no support, 10%, and 20% support), participants …

Results Of A Nine Month Home-Based Physical Activity Intervention For People Living With Hiv., Jason R. Jaggers, Joanna M. Snead, Felipe Lobelo, Gregory A. Hand, Wesley D. Dudgeon, Vivek K. Prasad, Stephanie Burgess, Steven N. Blair

Faculty and Staff Scholarship

Background: The purpose of this investigation was to test the feasibility of a home-based moderate-intensity physical activity (MPA) program for people living with HIV/AIDS (PLWHA) currently taking antiretroviral therapy (ART). Methods: 68 participants recruited for a 9-month home-based PA intervention aimed to reduce risk factors of cardiovascular disease for PLWHA taking ART. All participants received an educational weight loss workbook and a pedometer for self-monitoring of physical activity. The intervention group received elastic Therabands® for strength training in addition to telephone based behavioral coaching. Clinical assessments were conducted at baseline and each follow-up which also included psychometric questionnaires and PA …

Improving Power Output In Older Adults Utilizing Plyometrics In An Alterg Treadmill, Tyler Dobbs

Boise State University Theses and Dissertations

The purpose of this study was to compare functional strength and power output in older adults who completed plyometric training in an AlterG treadmill compared to older adults who completed traditional resistance training. Methods: Twenty-three older adults were randomized to a strength (SG), plyometric (PG), or control group (CG). SG and PG exercised 3x/week for 8 weeks while CG performed no exercise. Measures of a timed sit-to-stand, stair climb, estimated maximal muscular strength, and isokinetic power were taken at pre and post testing. A repeated measures 2x3 (time x group) ANOVA was used to determine if there was a significant …

Accuracy And Precision Of Quantitative 31p-Mrs Measurements Of Human Skeletal Muscle Mitochondrial Function, Gwenael Layec, J. R. Gifford, Joel D. Trinity, Corey R. Hart, Ryan S. Garten, Song-Young Park, Yann Le Fur, Eun-Kee Jeong, Russell S. Richardson

Health and Kinesiology Faculty Publications

Although theoretically sound, the accuracy and precision of 31P-magnetic resonance spectroscopy (31P-MRS) approaches to quantitatively estimate mitochondrial capacity are not well documented. Therefore, employing four differing models of respiratory control [linear, kinetic, and multipoint adenosine diphosphate (ADP) and phosphorylation potential], this study sought to determine the accuracy and precision of 31P-MRS assessments of peak mitochondrial adenosine-triphosphate (ATP) synthesis rate utilizing directly measured peak respiration (State 3) in permeabilized skeletal muscle fibers. In 23 subjects of different fitness levels, 31P-MRS during a 24-s maximal isometric knee extension and high-resolution respirometry in muscle fibers from the vastus lateralis was performed. Although significantly …

Fast Men Slow More Than Fast Women In A 10 Kilometer Road Race, Robert O. Deaner, Vittorio Addana, Rickey E. Carter, Michael J. Joyner, Sandra K. Hunter

Exercise Science Faculty Research and Publications

Background. Previous studies have demonstrated that men are more likely than women to slow in the marathon (footrace). This study investigated whether the sex difference in pacing occurs for a shorter race distance.

Materials & Methods. Data were acquired from the Bolder Boulder 10 km road race for the years 2008–2013, which encompassed 191,693 performances. There were two pacing measures, percentage change in pace of the first 3 miles relative to the final 3.2 miles and percentage change in pace of the first mile relative to the final 5.2 miles. Pacing was analyzed as a continuous variable and as two …

Adding Stiffness To The Foot Modulates Soleus Force-Velocity Behaviour During Human Walking, Kota Z. Takahashi, Michael T. Gross, Herman Van Werkhoven, Stephen J. Piazza, Gregory S. Sawicki

Journal Articles

Previous studies of human locomotion indicate that foot and ankle structures can interact in complex ways. The structure of the foot defines the input and output lever arms that influences the force-generating capacity of the ankle plantar flexors during push-off. At the same time, deformation of the foot may dissipate some of the mechanical energy generated by the plantar flexors during push-off. We investigated this foot-ankle interplay during walking by adding stiffness to the foot through shoes and insoles, and characterized the resulting changes in in vivo soleus muscle-tendon mechanics using ultrasonography. Added stiffness decreased energy dissipation at the foot …

A Bayesian Inference Comparing Collegiate Female Cyclists To Elite Female Cyclists From A Meta-Analysis, Frank B. Wyatt, Mihir Dhimar, Yesha Shah

International Journal of Exercise Science

International Journal of Exercise Science 9(3): 368-375, 2016. The aim of this study was to evaluate the physiological characteristics of competitive, collegiate female cyclists (CFC) to data of elite female cyclists (EFC) obtained from a meta-analytic review. Eleven (n=11) CFC volunteered as subjects. Subjects signed a university approved informed consent. Means and standard deviation (+ SD) were obtained from the following measurements: age (y), 22.5± 5.1; height (cm) 167.22 ± 6.2; body mass (kg) 63.78 ± 9.71; body fat (%) 22.9 ± 3.6. Subjects performed a maximal cycling ergometer test to volitional fatigue. Maximal oxygen consumption (VO2 max, mL*kg1*min.-1) …

Effects Of Static Stretching On Squat Performance In Division I Female Athletes, Clare F. Heisey, J. Derek Kingsley

International Journal of Exercise Science

International Journal of Exercise Science 9(3): 359-367, 2016. Static stretching was once recognized as a method of preparation for physical activity that would inhibit performance and increase risk of injury. However, a growing body of research suggests that static stretching may not have an inhibitory effect. Regardless, the data have not examined gender differences or the fatigue index (FI) and flexibility effects of static stretching on the back squat over multiple sets. Therefore, the purpose of this study was to examine the relationship between a static-stretch condition (SC) and control condition (CC) on flexibility and the FI of Division I …

Individual Differences In The Programming Of Rapid Bimanual Movements: Are Two Modes Better Than One?, Ashley N. Vander Does, David E. Sherwood

International Journal of Exercise Science

International Journal of Exercise Science 9(3): 347-358, 2016. One of the challenges in performing simultaneous bimanual movements is to prevent interference from one limb to the other, thereby maintaining spatial accuracy in both limbs. Prior research has shown that when a longer distance movement is performed with a shorter movement, the shorter movement overshoots its target and the longer movement undershoots its target relative to control conditions where two shorter or two longer movements are made. The current experiment investigated the motor control strategies used by participants when performing simultaneous aiming movements combining both different and same distances. Participants (N …

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

International Journal of Exercise Science

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

Power Training And Functional Performance In Middle Aged Women: A Pilot Study, Mitchel A. Magrini, J. Jay Dawes, Craig Elder, Mary Ann Kluge

International Journal of Exercise Science

International Journal of Exercise Science 9(3): 327-335, 2016. Muscular power is a key component of functional performance (FP) and fall risk reduction. The present study investigated the effect that power training with medicine balls had on body composition and FP in middle-age females. 10 women were divided into a control group (n=4, age=59.8+3.6) and an intervention group (n=6, age=59.5+3.6) in this 6-week study. The intervention group completed a medicine ball training program two times a week. Body composition and FP tests were administered prepost. Data was analyzed using a series of Wilcoxon Signed Ranks test and Cohen’s d test for …

Do Girls With Excess Adiposity Perform Poorer Motor Skills Than Their Leaner Peers?, Daniel V. Chagas, Joyce F. Carvalho, Luiz A. Batista

International Journal of Exercise Science

International Journal of Exercise Science 9(3): 318-326, 2016. The main aim of this study was to analyze the joint association of body fat percentage and physical activity levels on motor coordination scores in girls with different adiposity status. Sixty-eight school-aged children between 12 and 14 years participated in the study. Skinfold thickness was measured and the Körperkoordinationstest für Kinder test was administered. Participants completed a selfreporting questionnaire on physical activity. Children’s adiposity status was attributed in according to age-specific cutoff points of a Brazilian database. Analysis of Variance was used to compare motor coordination scores among groups with different status …