Physiology Commons^™

Evaluation Of Air Consumption And Work Efficiency In Structural Firefighters, Emily Lynn Langford

Theses and Dissertations--Kinesiology and Health Promotion

INTRODUCTION: For safe and efficient fireground performance, firefighters (FF) must consume air supplied by the self-contained breathing apparatus (SCBA) efficiently while sustaining high work rates. Firefighter research and fire department physical ability assessments typically quantify performance solely on task completion time (i.e., work rate), failing to consider the critical element of air consumption efficiency, which subsequently impacts the SCBA’s functional work duration. PURPOSES: (Arm 1, Aim #1) To examine variability in air consumption (AC) between FF during standardized pace tasks; (Arm 1, Aim #2) To evaluate AC efficiency (ACE) against a recognized metabolic-work rate concept of economy; (Arm …

Evidence Of Myomir Regulation Of The Pentose Phosphate Pathway During Mechanical Load-Induced Hypertrophy, Taylor Valentino, Vandre C. Figueiredo, C. Brooks Mobley, John J. Mccarthy, Ivan J. Vechetti Jr.

Physiology Faculty Publications

Many of the molecular and cellular mechanisms discovered to regulate skeletal muscle hypertrophy were first identified using the rodent synergist ablation model. This model reveals the intrinsic capability and necessary pathways of skeletal muscle growth in response to mechanical overload (MOV). Reminiscent of the rapid cellular growth observed with cancer, we hypothesized that in response to MOV, skeletal muscle would undergo metabolic programming to sustain increased demands to support hypertrophy. To test this hypothesis, we analyzed the gene expression of specific metabolic pathways taken from transcriptomic microarray data of a MOV time course. We found an upregulation of genes involved …

Lat1 Protein Content Increases Following 12 Weeks Of Resistance Exercise Training In Human Skeletal Muscle, Paul A. Roberson, Christopher Brooks Mobley, Matthew A. Romero, Cody T. Haun, Shelby C. Osburn, Petey W. Mumford, Christopher G. Vann, Rory A. Greer, Arny A. Ferrando, Michael D. Roberts

Physiology Faculty Publications

Introduction: Amino acid transporters are essential for cellular amino acid transport and promoting protein synthesis. While previous literature has demonstrated the association of amino acid transporters and protein synthesis following acute resistance exercise and amino acid supplementation, the chronic effect of resistance exercise and supplementation on amino acid transporters is unknown. The purpose herein was to determine if amino acid transporters and amino acid metabolic enzymes were related to skeletal muscle hypertrophy following resistance exercise training with different nutritional supplementation strategies.

Methods: 43 college-aged males were separated into a maltodextrin placebo (PLA, n = 12), leucine (LEU, n = 14), …

Examination Of Sex- And Limb-Specific Fatigue During Unilateral, Isometric Forearm Exercise, Caleb Christian Voskuil

Theses and Dissertations--Kinesiology and Health Promotion

The purpose of this study was to examine the effects of unilateral, isometric handgrip holds to failure for the dominant (Dm) and non-dominant (NDm) limb on ipsilateral ([IPS] exercised side) and contralateral ([CON] non-exercised side) performance fatigability. Twenty individuals participated in this study (Men [n =10]; Women [n = 10; Composite Demographics: Age: 22.2 years; Height: 174.4 cm; Body Mass: 75.0 kg) and completed three visits. Two, 6 s maximal voluntary isometric contractions (MVICs) for the Dm and NDm limb were performed during visit 1, followed by a familiarization of the fatigue test. Visits 2 and 3 included an isometric, …

Comparison Of The Times To Exhaustion, Physiological, Perceptual, And Neuromusuclar Responses During Constant Heart Rate, Constant Vo2, And Constant Power Exercise, Pasquale Jiovanni Succi

Theses and Dissertations--Kinesiology and Health Promotion

The purposes of this study were to: 1) Determine if there are differences in the sustainability of exercise when anchored at critical heart rate (CHR), the VO₂ associated with CHR (VO₂CHR), or the power output associated with CHR (PCHR); 2) examine the patterns of responses in power output, metabolic (heart rate [HR], VO₂, respiration rate [RR]), neuromuscular (electromyographic [EMG] amplitude [AMP], mean power frequency [MPF], mechanomyographic [MMG] AMP and MPF, perceptual (rating of perceived exertion [RPE]), and muscle oxygenation responses (%SmO₂) during exercise anchored by HR, VO₂, and power output; and …

Quadriceps Recruitment And Twitch Properties In Lean And Obese Women Before And After Fatiguing Exercise, Rebekah Seay Carpenter

Theses and Dissertations--Kinesiology and Health Promotion

Skeletal muscle strength, specifically that of the anti-gravitational muscles such as the quadriceps, is essential for performing dynamic tasks including walking, navigating stairs, and transitioning between sitting and standing. Obesity has been shown to negatively impact musculoskeletal function and decrease quadriceps strength relative to body weight. Additionally, obesity has been linked with higher rates of fatigue and lower strength outcomes following a test of muscular endurance of the quadriceps. Since obesity lowers relative strength, it is likely that quadriceps muscle weakness contributes to reduced physical function of dynamic tasks. However, to date, the precise mechanism for obesity-induced muscle weakness has …

Appetite-Regulating Hormones In Energy Compensation With Exercise, Jack Moreland

Theses and Dissertations--Nutrition and Food Systems

Background: The appetite-regulating hormones may influence compensatory increases in energy intake with exercise, although this causal relationship has been difficult to prove in a longitudinal trial.

Methods: 37 participants (29 female) aged 18 to 40 years performed aerobic exercise 6 days (6d), 2 days (2d), or 0 days per week for 12-weeks. Concentrations of ghrelin, leptin, glucagon-like peptide 1 (GLP-1), and insulin were assessed before (fasting, minute 0) and after a standardized meal at minute 15, 30, 45, 60, 90, 120, 150, and 180. Linear mixed-effects models were used to model the relationships between time point (12 weeks vs. baseline) …

The Effect Of Coronal Prosthetic Alignment Changes On Socket Reaction Moments, Spatiotemporal Parameters, And Perception Of Alignment During Gait In Individuals With Transtibial Amputation, Hiroshi Hashimoto, Toshiki Kobayashi, Fan Gao, Masataka Kataoka, Kuniharu Okuda

Kinesiology and Health Promotion Faculty Publications

Introduction: The alignment of a prosthesis is clinically determined based on observations by clinicians and the subjective perception of amputees during gait. However, this process has been reported to be unreliable. Socket reaction moment has been reported to be significantly impacted by alignment changes, but the impact of these alignment changes on other gait parameters is unclear. The aim of this study was to investigate the effects of coronal alignment changes of a transtibial prosthesis on socket reaction moment, spatiotemporal parameters, and perceptions of alignment during gait in amputees.

Methods: Nine individuals with transtibial amputation participated in this study. Socket …

Acute Resistance Exercise Induces Sestrin2 Phosphorylation And P62 Dephosphorylation In Human Skeletal Muscle, Nina Zeng, Randall F. D'Souza, Vandre C. Figueiredo, James F. Markworth, Llion A. Roberts, Jonathan M. Peake, Cameron J. Mitchell, David Cameron-Smith

Center for Muscle Biology Faculty Publications

Sestrins (1, 2, 3) are a family of stress-inducible proteins capable of attenuating oxidative stress, regulating metabolism, and stimulating autophagy. Sequestosome1 (p62) is also a stress-inducible multifunctional protein acting as a signaling hub for oxidative stress and selective autophagy. It is unclear whether Sestrin and p62^Ser403 are regulated acutely or chronically by resistance exercise (RE) or training (RT) in human skeletal muscle. Therefore, the acute and chronic effects of RE on Sestrin and p62 in human skeletal muscle were examined through two studies. In Study 1, nine active men (22.1 ± 2.2 years) performed a bout of single-leg strength …

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 …

Central And Peripheral Weight Gain Affect Trunk Kinematics And Lower-Extremity Muscle Activation Differently During Sit-To-Stand, Michelle Christine Walaszek

Theses and Dissertations--Kinesiology and Health Promotion

Background: Obesity-induced alterations in biomechanics and muscle recruitment during activities of daily living, such as sit-to-stand (STS) are often attributed to increases in adipose tissue (AT) mass. Central or peripheral distribution of AT may differently affect biomechanics and muscle recruitment.

Methods: Fifteen healthy, normal weight (BMI 22.4 ± 1.9 kg/m², 24.1 ± 4.2 years) subjects volunteered. External loads equivalent to a 5 kg/m² BMI increase were applied in three conditions: unloaded (UN), centrally loaded (CL), and peripherally loaded (PL). Subjects completed three successful STS movements in a backless chair under each load condition in random order. Motion …

Workforce Fitness: Description, Contextual Issues, And Implications For Public Health, Nicolaas P. Pronk

Frontiers in Public Health Services and Systems Research

Workforce fitness matters for the prevention of premature death, chronic diseases, productivity loss, excess medical care costs, loss of income or family earnings, and other social and economic concerns. Yet fitness levels appear to be relatively low and declining. Over the past half century obesity has doubled, physical activity levels are below par, and cardiorespiratory fitness often does not meet minimally acceptable job standards. During this time, daily occupational energy expenditure has decreased by more than 100 calories. It is recommended for employers to consider best practices and design workplace wellness programs accordingly. Regulations that protect and promote worker health, …

The Effects Of Spinal Manipulative Therapy On Isokinetic Strength And Postactivation Potentiation, Grant D. Sanders

Theses and Dissertations--Kinesiology and Health Promotion

Spinal manipulative therapy (SMT) is a therapeutic procedure employed by various healthcare practitioners for alleviating acute and chronic musculoskeletal complaints. This form of treatment is also delivered to enhance the performance and augment the rehabilitation of athletes. However, despite research findings alleging the strength-modulating effects of SMT alongside numerous professional athletes’ positive anecdotal claims concerning its results, the physiological processes to explain its effects remain largely unexplained. Therefore, the purpose of this work was to investigate the effects of SMT in a college-aged sample population with two experiments.

The first study examined the effect of SMT targeting the lumbosacral region …