Life Sciences Commons^™

Impact Of Extremely Low-Frequency Magnetic Fields On Human Postural Control, Alicia N. Allen

Electronic Thesis and Dissertation Repository

The general public and workers can be exposed to high-levels of power-line frequency magnetic fields (MFs - up to 10 mT). Although such time-varying MFs have the potential to modulate human postural control, no existing studies have explored MF exposure levels that possibly trigger acute sway responses. This work evaluates time-varying MF exposure (up to 100 mT) in the extremely low frequency range (ELF – up to 300 Hz) and its effects on human postural control. Twenty-two healthy participants were each exposed to randomized, 5-second MF and electric stimulations (0, 50 and 100 mT and 1.5 mA respectively) given at …

The Use Of P3b As An Indicator Of Neurophysiologic Change From Subconcussive Impacts In Football Players, Jeffrey S. Brooks

Electronic Thesis and Dissertation Repository

There is a growing appreciation in research that subconcussive impacts may affect cognitive functioning. Canadian University football players (n=45) were separated into three groups based on their position/skill (small skilled, big skilled and big unskilled). An impact measuring device (GForceTracker) was used to record the number of impacts that each player experienced in a season. Player groups were separated into two levels of impact exposure: low and high. Players completed baseline, midseason, postseason, and follow-up neurophysiological tests (four months later) to measure P3b amplitude in response to a visual oddball paradigm, and high versus low impact subgroups for each player …

The Effects Of Ice Hockey Goaltender Leg Pads On Safety And Performance, Ryan J. Frayne

Electronic Thesis and Dissertation Repository

Ice hockey goaltenders have the highest percentage of cam-type femoroacetabular impingement (FAI). The exact cause of these injuries in goaltenders remains unknown; however, it has been suggested that common goaltender movements and a goaltender’s underlying hip pathology may be contributing factors. The butterfly save technique, commonly used by goaltenders, has been linked to FAI. Simply stopping these movements would likely be detrimental to goaltender performance. Therefore, changing other aspects of goaltending, such as altering the goaltender equipment, should be considered. The overall objective of this thesis was to understand how ice hockey goaltender leg pads influence both the safety and …

Effect Of Terminal Haptic Feedback On The Sensorimotor Control Of Visually And Tactile-Guided Grasping, Shirin Davarpanah Jazi

Electronic Thesis and Dissertation Repository

When grasping a physical object, the sensorimotor system is able to specify grip aperture via absolute sensory information. In contrast, grasping to a location previously occupied by (no-target pantomime-grasp) or adjacent to (spatially dissociated pantomime-grasp) an object results in the specification of grip aperture via relative sensory information. It is important to recognize that grasping a physical object and pantomime-grasping differ not only in terms of their spatial properties but also with respect to the availability of haptic feedback. Thus, the objective of this dissertation was to investigate how terminal haptic feedback influences the underlying mechanisms that support goal-directed grasping …

The Neuroprotective Effects Of Endurance Training On The Aging Brain, Katelyn Norton

Electronic Thesis and Dissertation Repository

Dysregulation of autonomic control often develops with advancing age, favoring a chronic state of heightened sympathetic outflow with parasympathetic withdrawal. However, the mechanisms of this age-related autonomic impairment are not known and may relate to alterations in brain structure (e.g. cortical atrophy) and/or altered neural function, particularly in regions related to the cortical autonomic network, namely, the medial prefrontal cortex (MPFC), insula cortex (IC), and hippocampus (HC). Exercise exerts beneficial effects on brain structure and, in the case of cognition, neurologic function; however, how exercise affects regions of the brain related to autonomic function are not known. This thesis tested …

Indicator Amino Acid Derived Estimates Of Dietary Protein Requirement In Exercise-Trained Individuals, Arash Bandegan

Electronic Thesis and Dissertation Repository

Despite a number of nitrogen balance (NB) studies indicating increased dietary protein needs in Endurance (ET) and strength (ST) trained athletes, the Institute of Medicine (2005) has concluded, based largely on methodological concerns, that “no additional dietary protein is suggested for healthy adults undertaking resistance or endurance exercise”. Indicator amino acid oxidation method (IAAO) has been recently used for determination of protein requirement in humans. This method is based on the concept that when one indispensable amino acid (AA) is deficient for protein synthesis, then all other AA, including the indicator, will be considered excess and oxidized. With increasing intakes …

Using An Aerial Drone To Examine Lateral Movement In Sweep Rowers, Joseph S. Munn

Electronic Thesis and Dissertation Repository

Rowing is a sport that is performed on the water, because of this there are many challenges associated with studying rowing. The primary challenges are an inability to control the environment and limitations with the equipment that can be used to collect data on the water. In order to try and overcome some of these challenges an aerial drone fitted with a high resolution camera was used to examine an understudied element of the rowing stroke, lateral movement in sweep rowers. Oar and shoulder angles and lateral movement of the shoulders and hands were calculated and compared between five different …

Constraining Kinematics During Single-Leg Squats And Step-Ups Can Reduce Quadratus Lumborum Activation And Facilitate Gluteal Activation, Shaylyn Kowalchuk

Electronic Thesis and Dissertation Repository

Increased quadratus lumborum activation and decreased gluteal activation may lead to lateral pelvic drop and increased hip adduction and internal rotation during single-leg exercises. These activation patterns and motions are associated with low back pain or lower extremity injuries. The purpose of this study was to evaluate if mechanically restricting hip adduction and internal rotation of the femur affected muscle activation. Twenty female track and field athletes performed single-leg squats and step-ups, and the quadratus lumborum, gluteus medius and maximus muscles activations were measured with surface electromyography. This study tested the hypothesis that mechanically restricted exercises would decrease quadratus lumborum …

Effects Of Aging And Coronary Artery Disease On Sympathetic Neural Recruitment Strategies During End-Inspiratory And End-Expiratory Apnea, Mark B. Badrov, Sophie Lalande, T Dylan Olver, Neville Suskin, J Kevin Shoemaker

Kinesiology Publications

In response to acute physiological stress, the sympathetic nervous system modifies neural outflow through increased firing frequency of lower-threshold axons, recruitment of latent subpopulations of higher-threshold axons, and/or acute modifications of synaptic delays. Aging and coronary artery disease (CAD) often modify efferent muscle sympathetic nerve activity (MSNA). Therefore, we investigated whether CAD (n = 14; 61 ± 10 yr) and/or healthy aging without CAD (OH; n = 14; 59 ± 9 yr) modified these recruitment strategies that normally are observed in young healthy (YH; n = 14; 25 ± 3 yr) individuals. MSNA (microneurography) was measured at baseline and during …

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 …

Relationships Among Self-Efficacy, Implicit Associations, Motives And Exercise Behaviour, Alison Divine

Electronic Thesis and Dissertation Repository

The general purpose of this dissertation was to examine how self-efficacy, explicit exercise motives and implicit automatic associations with exercise influence exercise behaviour of sedentary adults. This dissertation is divided into three manuscripts. The first manuscript examined how self-selection influences the decision to enrol in an exercise program as well as in self-efficacy, explicit motives and implicit associations. Additionally, manuscript one sought to understand the role of self-selection bias in the adoption and maintenance of exercise over six months. A total of 290 inactive adults aged 35-65 completed the Multidimensional Self-Efficacy for Exercise Scale (MSES; Rodgers, Wilson, Hall, Fraser, & …

Inpatient Versus Outpatient Total Hip Arthroplasty, Michael Pollock

Electronic Thesis and Dissertation Repository

We conducted a randomized controlled trial to evaluate patients undergoing a total hip arthroplasty (THA) who were discharged from the hospital either on the day of surgery (outpatient) or were admitted overnight following surgery (inpatient). Our primary outcome was the rate of serious adverse events during the first three months postoperatively. Secondary outcome measures included cost, patient satisfaction, functional outcomes, quality of life and pain. We found no statistically significant difference between the two groups in serious adverse events. We found that outpatient THA was less expensive from the perspectives of the hospital and ministry of health; but the difference …

Effects Of Acute And Chronic Interval Sprint Exercise Performed On A Manually Propelled Treadmill On Upper Limb Vascular Mechanics In Healthy Young Men., T Dylan Olver, Steph M Reid, Alan R Smith, Mair Zamir, Peter W R Lemon, M Harold Laughlin, J Kevin Shoemaker

Kinesiology Publications

Interval sprint exercise performed on a manually propelled treadmill, where the hands grip the handle bars, engages lower and upper limb skeletal muscle, but little is known regarding the effects of this exercise modality on the upper limb vasculature. We tested the hypotheses that an acute bout of sprint exercise and 6 weeks of training induces brachial artery (BA) and forearm vascular remodeling, favoring a more compliant system. Before and following a single bout of exercise as well as 6 weeks of training three types of vascular properties/methodologies were examined in healthy men: (1) stiffness of the entire upper limb …

Impact Of Long-Term Endurance Training Vs. Guideline-Based Physical Activity On Brain Structure In Healthy Aging, Katelyn N. Wood, Robert Nikolov, J Kevin Shoemaker

Kinesiology Publications

Brain structure is a fundamental determinant of brain function, both of which decline with age in the adult. Whereas short-term exercise improves brain size in older adults, the impact of endurance training on brain structure when initiated early and sustained throughout life, remains unknown. We tested the hypothesis that long-term competitive aerobic training enhances cortical and subcortical mass compared to middle to older-aged healthy adults who adhere to the minimum physical activity guidelines. Observations were made in 16 masters athletes (MA; 53 ± 6 years, VO2max = 55 ± 10 ml/kg/min, training > 15 years), and 16 active, healthy, and cognitively …

Risk Taking By Children And Seniors: Selected Sandwich Generation Caregiver’S Perceptions, Trevor J. Hines Duncliffe

Electronic Thesis and Dissertation Repository

Grounded theory was used to investigate the perception of risk held by 20 women in the sandwich generation and their process to evaluate risk as caregivers for both their child and senior. The impact of their risk perception was considered as it related to their actions, the child’s and senior’s ability to engage in risk taking, their independence and quality of life. Findings suggest the same risk assessment process was used to determine if the child or senior is capable of managing the risk. The independence gained by both through risk taking is supported unless safety is a factor. As …

Effects Of An In-Bed Resistance Exercise Program For Hospitalized High Risk Pregnant Women On Postpartum Functional Ability And Psychosocial Health, Charity Mccarthy

Electronic Thesis and Dissertation Repository

Hospitalised high-risk pregnant women (HHRPW) report physiological deconditioning similar to non-pregnant bed-rested patients. The purpose of this pilot study was to evaluate the effectiveness of an in-bed resistance exercise program to reduce the side-effects of activity-restriction in HHRPW. It was hypothesized that HHRPW who exercised while in hospital would have better functional ability and a higher quality of life at two months postpartum compared to HHRPW with no exercise program. HHRPW were activity-restricted (1940 ±1405 steps/day) in hospital and reported high rates of anxiety and depression. Nine women were randomized to either a supervised in-bed exercise (n=5) or into a …

Markerless Radiostereogammetry Of The Shoulder Joint In Humans: Comparisons Of Scapulohumeral Kinematics Between Individuals With Healthy And Supraspinatus-Impaired Shoulders, Ashley N. Hannon

Electronic Thesis and Dissertation Repository

The purpose of this collection of studies was to further develop the knowledge of shoulder motion in order to better understand joint function through direct measurement of 3D scapulohumeral joint kinematics using a technique of high accuracy. Markerless, bi-planar fluoroscopic radiostereometric analysis using a generic shoulder model was developed in this thesis, reducing the amount of radiation exposure to subjects. The studies compared kinematic data of the scapulohumeral joint in six degrees of freedom with a precise, in-vivo measuring technique. Data were collected on young and older healthy individuals, individuals with a torn supraspinatus and post-surgical intervention.

Although this generic …

The Utility Of A Protection Motivation Theory Framework For Understanding Sedentary Behavior, Tiffany S. Wong, Anca Gaston, Stefanie Dejesus, Harry Prapavessis

Kinesiology Publications

Multilevel determinants of sedentary behavior (SB), including constructs couched within evidence-based psychological frameworks, can contribute to more efficacious interventions designed to decrease sitting time. This study aimed to: (1) examine the factor structure and composition of sedentary-derived protection motivation theory (PMT) constructs and (2) determine the utility of these constructs in predicting general and leisure sedentary goal intention (GI), implementation intention (II), and self-reported SB. Sedentary-derived PMT (perceived severity, PS; perceived vulnerability, PV; response efficacy, RE; self-efficacy, SE), GI, and II constructs, and a modified SB questionnaire were completed by undergraduate students (n = 596). SE was broken into …