Exercise Physiology Commons^™

Influence Of Deception Of Task Duration On The Sex-Specific Physiological, Neuromuscular, And Affective Responses To Rpe-Clamp Cycle Ergometry, Pasquale Succi

Theses and Dissertations--Kinesiology and Health Promotion

Several theories exist to explain the interaction of sensory afferent feedback and efferent feedforward signals on the generation of a rating of perceived exertion (RPE) which influence endurance exercise pacing and performance. Within these theories, exists the premise that the expected duration of exercise plays a role within the generation of an individual’s RPE and their endurance performance. Previous work has demonstrated equivocal findings of this influence, while other research has suggested potential differences between males and females. However, an RPE-clamp model, where the external workload is modulated to maintain a constant perceptual intensity, has not previously been used to …

Reliability And Validity Of A Commercial Running Power Meter To Indicate Metabolic Workload During Endurance Running, James Harris Hudgins Iii

Theses and Dissertations--Kinesiology and Health Promotion

Commercial running power (RP) meters may provide endurance runners and coaches with improved precision for monitoring running intensity. Cyclists rely upon the relationship between cycling power and metabolic demand to regulate physiological intensity during training and racing, independent of changes in the physical environment (e.g., terrain, wind). Research demonstrates strong reliability and validity for a specific RP meter to indicate metabolic demand within controlled running conditions. However, several potential influences on this relationship have not been investigated. Therefore, four studies were conducted with the following aims:

- Study 1: Determine the inter-limb reliability and validity of a single-limb-based RP meter …

Maximal Strength Training Increases Metabolic Energy Expenditure In Sedentary Adults Classified As Obese, Robert E. Anderson Iii

Theses and Dissertations--Nutrition and Food Systems

Background: Metabolic adaptations reduce resting and non-resting energy expenditure to account for approximately 120 kcal/day. Weight loss promotes greater skeletal muscle efficiency, reducing the energy cost of physical activity and is correlated with declines in skeletal muscle glucose oxidation. Maximal Strength Training (MST) has the potential to upregulate glucose utilization and may offset these metabolic adaptations. Objective: To determine if MST offsets markers of metabolic adaptation by increasing resting and non-resting energy expenditure in sedentary individuals classified as obese. Methods: Five (5) participants (2 females, 3 males), ages 18-35 years, with obesity (BMI 30–45 kg/m2) were enrolled in an 8-week …

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 …

Regulation Of Skeletal Muscle Plasticity By The Gut Microbiome, Taylor R. Valentino

Theses and Dissertations--Physiology

Recent evidence suggests that the gut microbiome could play a role in skeletal muscle plasticity, providing novel treatments for muscle wasting diseases and/or performance enhancements. I first sought to determine if the gut microbiome is necessary for skeletal muscle adaptation to exercise. Forty-two, four-month old, female C57Bl/6J underwent nine weeks of weighted wheel running or remained in cage with a locked wheel, without or without the administration of antibiotics (treated). In response to wheel running, I found that antibiotic depletion of the microbiome led to a blunted hypertrophic response in the soleus muscle as measured by normalized muscle wet weight …

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 …

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, …

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 …

Predictors Of Work Economy In Structural Firefighters, Maxwell Steele Norris

Theses and Dissertations--Kinesiology and Health Promotion

The purpose of this study was to investigate a novel work economy metric to quantify firefighter physical ability and identify physical fitness and anthropometric correlates of work economy. Physical fitness and anthropometric measurements were taken on 19 incumbent structural firefighters (Age: 35.0±7.1 yr, Body mass: 87.5±13.1 kg). Firefighters performed a timed maximal effort simulated fireground test (SFGT) in personal protective equipment. SFGT air depletion was represented by change in cylinder pressure. Work economy was quantified as: (1/(SFGT completion time x air depletion))x10⁴. Bivariate and multiple linear regression analyses were used to identify anthropometric and physical fitness predictors of …

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) …

Physiological Differences Between Low Versus High Skeletal Muscle Hypertrophic Responders To Resistance Exercise Training: Current Perspectives And Future Research Directions, Michael D. Roberts, Cody T. Haun, Christopher B. Mobley, Petey W. Mumford, Matthew A. Romero, Paul A. Roberson, Christopher G. Vann, John J. Mccarthy

Physiology Faculty Publications

Numerous reports suggest there are low and high skeletal muscle hypertrophic responders following weeks to months of structured resistance exercise training (referred to as low and high responders herein). Specifically, divergent alterations in muscle fiber cross sectional area (fCSA), vastus lateralis thickness, and whole body lean tissue mass have been shown to occur in high versus low responders. Differential responses in ribosome biogenesis and subsequent protein synthetic rates during training seemingly explain some of this individual variation in humans, and mechanistic in vitro and rodent studies provide further evidence that ribosome biogenesis is critical for muscle hypertrophy. High responders may …

Β-Catenin Regulation Of Adult Skeletal Muscle Plasticity, Yuan Wen

Theses and Dissertations--Physiology

Adult skeletal muscle is highly plastic and responds readily to environmental stimuli. One of the most commonly utilized methods to study skeletal muscle adaptations is immunofluorescence microscopy. By analyzing images of adult muscle cells, also known as myofibers, one can quantify changes in skeletal muscle structure and function (e.g. hypertrophy and fiber type). Skeletal muscle samples are typically cut in transverse or cross sections, and antibodies against sarcolemmal or basal lamina proteins are used to label the myofiber boundaries.

The quantification of hundreds to thousands of myofibers per sample is accomplished either manually or semi-automatically using generalized pathology software, and …

Vocal Function Exercises For Normal Voice: With And Without Semi-Occlusion, Megan Suzanne Brown

Theses and Dissertations--Communication Sciences and Disorders

The primary purpose of this investigation was to explore the effects of varying degrees of vocal tract semi-occlusion in Vocal Function Exercises (VFEs) on attainment of pre- established maximum phonation time (MPT) goals in individuals between the ages of 18 and 45 with normal voice. Individuals were randomized into three experimental groups: the traditional VFE with a semi-occluded vocal tract (SOVT), modified /o/ with partial occlusion, and modified /a/ without significant occlusion. For six weeks, the participants completed the four exercises two times each, twice daily on corresponding vocal tract postures assigned by group. Results indicated significant change in percent …

Calcitriol Increases Ceramide, Diacylglycerol, And Expression Of Genes Involved In Lipid Packaging In Skeletal Muscle, Grace Elizabeth Jefferson

Theses and Dissertations--Kinesiology and Health Promotion

Background: Vitamin D is crucial for skeletal muscle function. 25-hidroxyvitamin D (25(OH)D) has been correlated with skeletal muscle mass and intramyocellular lipid (IMCL) content. The purpose of this study was to understand how calcitriol, the active vitamin D metabolite, directly affects myocellular size and lipid partitioning.

Methods: C₂C₁₂ myotubes were treated with calcitriol (100nM) or vehicle control for 24 or 96 h. Myotube diameter and protein synthesis rate were measured to determine effects of calcitriol on myocellular size. Intramyocellular triacylglycerol (IMTG), diacylglycerol (DAG), and ceramide content were measured by LC/MS. Expression of genes involved in lipid packaging …

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 …

Bovine Colostrum Supplementation Optimises Earnings, Performance And Recovery In Racing Thoroughbreds, C. K. Fenger, Thomas Tobin, P. J. Casey, Edward A. Roualdes, J. L. Langemeier, D. M. Haines

Maxwell H. Gluck Equine Research Center Faculty Publications

Bovine colostrum (BC) is the first milk produced by cows after calving and contains numerous beneficial substances for the immunity and development of the newborn calf. Because of the growth and immune factors in BC, it has become an attractive supplement for use by athletes to support immunity and health during athletic performance. In order to evaluate the effects of oral BC supplementation on equine athletes, this study evaluated the earnings, performance, recovery and incidence of upper respiratory infections (URTI) in racing horses. The study design was a randomized cross-over racing performance study. 21 horses in race training were randomly …