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Neuromuscular Function Following Lengthening Contractions, Geoffrey A. Power Dec 2012

Neuromuscular Function Following Lengthening Contractions, Geoffrey A. Power

Electronic Thesis and Dissertation Repository

Unaccustomed lengthening contractions have been shown to impair muscle function - however little is known regarding this impairment on muscle power - specifically, the velocity component of power during voluntary contractions in humans. The four studies presented in my thesis investigated power-loss following lengthening contractions in healthy young and old women and young men.

The purpose of Study 1 was to determine reliability of velocity-dependent power of the dorsiflexors using the isotonic mode of the Biodex Dynamometer. I determined the isotonic mode is reliable and can be used to track changes in velocity and power following fatigue and lengthening contractions.

The purpose ...


Neuroprotective Effects Of Long-Term Endurance Training On The Cortical Autonomic Network In The Aging Brain, Torri A. Luchyshyn Oct 2012

Neuroprotective Effects Of Long-Term Endurance Training On The Cortical Autonomic Network In The Aging Brain, Torri A. Luchyshyn

Electronic Thesis and Dissertation Repository

This study tested whether long-term endurance training in older adults (ET; n = 15, 55 ± 4 years, relative VO2max = 50 ± 8 ml/kg/min) would alter cardiovagal control and preserve the cortical autonomic network compared to age-matched controls (CON; n = 15, 56 ± 4 years, relative VO2max = 37 ± 9 ml/kg/min). The hypothesis predicts 1) altered deactivation patterns of the ventral medial prefrontal cortex (vMPFC) in response to isometric hand grip (IHG) and 2) greater indices of cardiovagal control; a) increased baroreflex sensitivity at rest, b) greater heart rate change (ΔHR) and c) reductions in high frequency ...


Task-Dependent Properties Of The Human Anconeus Muscle, Brad Harwood Aug 2012

Task-Dependent Properties Of The Human Anconeus Muscle, Brad Harwood

Electronic Thesis and Dissertation Repository

Recording motor unit (MU) action potentials during fast muscle contractions, specifically during movement, presents unique challenges that constrain the investigation of the upper limits of human MU performance. The anconeus muscle exhibits many advantageous characteristics that suggest it is an appealing model for the study of MU behaviour in challenging experiment paradigms. Thus, the purpose was to determine the MU recruitment and discharge properties associated with the generation of movement up to maximal angular velocities of elbow extension and to determine the effect of submaximal fatiguing movements on these MU properties. Due to the synergistic nature of the anconeus in ...


Overweight In Infants Increases The Chance Of Having A Gross Motor Developmental Delay At Six Months, Meredith Parkovnick Aug 2012

Overweight In Infants Increases The Chance Of Having A Gross Motor Developmental Delay At Six Months, Meredith Parkovnick

Electronic Thesis and Dissertation Repository

The objective of the present study was to explore the relationship between overweight infants and gross motor development at six months. A secondary purpose was to determine whether gross motor development varied according to sleep position. Eighteen mother-infant pairs participated. Motor development was assessed using the Alberta Infant Motor Scale (AIMS). Sleeping position was determined by maternal report based on the position in which the infant awoke. At six months, overweight infants scored lower (worse) on the AIMS test than normal weight infants, even after controlling for sleep position. Infants who slept in the supine position scored lower on the ...


The Effects Of Sprint Interval Training On Endothelial Function In Young Men And Women, Stephanie M. Reid Aug 2012

The Effects Of Sprint Interval Training On Endothelial Function In Young Men And Women, Stephanie M. Reid

Electronic Thesis and Dissertation Repository

The benefits of exercise training on endothelial function in the healthy young population are unclear. This study was designed to assess the effects of sprint interval training (SIT; 4-7 x 30-45 s all out exercise efforts separated by 4 min of recovery, repeated 3-4 times/wk over 6 wk) on endothelial function of the superficial femoral artery (SFA) in young recreationally active men and women. Twenty-one men and twenty women arrived at the laboratory after >3 h fast and were assigned randomly to SIT or Control (no training) groups. SFA diameter and blood velocity (BV) were assessed using Doppler ultrasound ...


School-Based Physical Activity In Children: An Evaluation Of The Daily Physical Activity Program In Ontario Elementary Schools., Ian T. Patton Aug 2012

School-Based Physical Activity In Children: An Evaluation Of The Daily Physical Activity Program In Ontario Elementary Schools., Ian T. Patton

Electronic Thesis and Dissertation Repository

Ontarioimplemented the Daily Physical Activity program in all elementary schools to counteract the recent decline in children’s physical activity levels. The program mandates that all students in kindergarten to grade 8 are provided with 20 minutes of physical activity every day. The purpose of this thesis was to evaluate the delivery of Daily Physical Activity as well as identify any supports or barriers to program delivery.

Study 1 consisted of a questionnaire investigating the perspectives of the teachers involved in the Daily Physical Activity program. Teachers were questioned about how they implement the DPA program, the supports and barriers ...


Effect Of Sledge Hockey Configuration On Sledge Hockey Performance, Cliff Worden-Rogers Aug 2012

Effect Of Sledge Hockey Configuration On Sledge Hockey Performance, Cliff Worden-Rogers

Electronic Thesis and Dissertation Repository

The purpose of this study was to evaluate the position of a sledge hockey player in their sledge using measurements of knee angle, seat height, and stability. Prior to this study, sledge hockey coaches and athletes used trivial methods to position a player in their seat. Proper positioning can enhance performance and function of the athlete. Nine different positions were evaluated using two on-ice sledge hockey specific tests. Four experienced male sledge hockey players from the London Blizzard who compete in the Ontario Sledge Hockey Association participated in this study. The results suggest a knee angle of 140º with a ...


Examining The Relationships Between Imagery, Sport Motivation, And Athletic Identity In Curling, Nicole Westlund Aug 2012

Examining The Relationships Between Imagery, Sport Motivation, And Athletic Identity In Curling, Nicole Westlund

Electronic Thesis and Dissertation Repository

Imagery use, motivation, and athletic identity all have been investigated in sport; however, a study examining the relationships among these three constructs has yet to be conducted. The participants (N = 213) were club and competitive curlers (Mage = 49.0; SD = 15.39). Results showed that athletic identity was significantly correlated with all five imagery functions and six behavioural regulations (p < .01) except for external regulation and amotivation. Multiple regression analyses predicting imagery use from both the behavioural regulations and athletic identity were conducted for each imagery function in club and competitive curlers. Athletic identity, identified regulation, and integrated regulation emerged as significant predictors of imagery use (p < .05). These findings suggest that there is a link between imagery use, motivation, and athletic identity. Researchers and sport psychologists can use these findings to develop more effective psychological skills training programs to improve the performance of curlers.


Early Child Care And Adiposity At Kindergarten Entry, Jessica D. Mackle Aug 2012

Early Child Care And Adiposity At Kindergarten Entry, Jessica D. Mackle

Electronic Thesis and Dissertation Repository

The association between pre-school child care participation and markers of adiposity at kindergarten entry was examined using parent reported previous child care exposure and directly measured body mass index (BMI) and waist circumference (WC) of kindergarten children (N=201; boys=106, girls=95). It was hypothesized that kindergarten children with previous exposure to full-time non-parent child care (FNPC; >20h/week) would have increased risk of overweight/obesity (BMI≥ 85th percentile) and high central adiposity (WC ≥80th percentile) compared to parent care (PC). The data suggest that there was no significant relationship between FNPC (n=112) and risk of ...


The Measurement Of Physical Activity And Self-Efficacy In Adolescents: Prospects, Problems, And Future Directions, Nerissa J. Campbell Jun 2012

The Measurement Of Physical Activity And Self-Efficacy In Adolescents: Prospects, Problems, And Future Directions, Nerissa J. Campbell

Electronic Thesis and Dissertation Repository

The objective of this dissertation was to address salient conceptual and measurement issues related to physical activity and self-efficacy in adolescents. Building upon previous physical activity device validation studies, Study 1 investigated the measurement of agreement between the Actiheart (a combined heart rate monitor and accelerometer device) and doubly labeled water (DLW) for estimating free-living physical activity energy expenditure (PAEE) in a sample of adolescents. The Actiheart was found to overestimate PAEE compared to DLW by a mean difference of 9.80 kcal∙kg-1∙d-1 (95% limits of agreement: -21.22 to 1.72 kcal∙kg-1∙d ...


Electroencephalographic Correlates Of Spatial Attention Index The Degree Of Online Control In Goal-Directed Reaching, Ali Mulla Jun 2012

Electroencephalographic Correlates Of Spatial Attention Index The Degree Of Online Control In Goal-Directed Reaching, Ali Mulla

Electronic Thesis and Dissertation Repository

Goal-directed reaches performed with limb vision (i.e., closed-loop: CL) are more accurate than their limb occluded (i.e., open-loop: OL) counterparts. This finding is frequently attributed to the use of online limb vision to effect trajectory amendments. Notably, however, the central planning of CL and OL reaches may also influence trajectory control. To that end, I examined the behavioural and event-related brain potentials (ERP) of reaches in a target perturbation paradigm wherein information regarding the nature of response (CL or OL) was provided prior to response cuing. CL reaches exhibited earlier and more effective trajectory amendments than OL reaches ...


Gait Variability Is An Independent Marker Of Frailty, Anam Islam May 2012

Gait Variability Is An Independent Marker Of Frailty, Anam Islam

Electronic Thesis and Dissertation Repository

The objectives of this study were to 1) determine if high gait variability is associated with frailty; 2) test the inter-rater reliability of the Clinical Frailty Scale (CFS) and its concurrent validity against the Frailty Phenotype Index (FPI) in classifying frailty. Frailty status was determined by applying the FPI and CFS to the sample of 107 community-dwelling older adults. Inter-rater reliability of the CFS was assessed using kappa statistics. Mantel-Haenszel test for trends evaluated concurrent validity of the CFS against the FPI components. Quantitative gait variables were assessed with an electronic walkway. Multivariable linear regression analysis evaluated the outcome of ...


The Effect Of An Acute Bout Of Exercise On Smoking Topography, Terri L. Schneider Apr 2012

The Effect Of An Acute Bout Of Exercise On Smoking Topography, Terri L. Schneider

Electronic Thesis and Dissertation Repository

This pilot study aimed to examine the effect of an acute bout of exercise on smoking behavior (topography) subsequent to a temporary period of smoking abstinence. Forty-three adult smokers (female = 34, Mage = 43.14), who had been smoking for an average of 23.90 years, were randomized to either an exercise (n = 21) or passive sitting group. Thirty-one smokers completed the study. The primary outcome variables included: puff count, puff volume, puff duration, inter-puff interval (IPI), and total cigarette duration. The effect of exercise on smoking topography was non-significant. Overall, the effectiveness of exercise as an additional harm reduction ...


Mmasculinities: Spectacular Narratives Of Masculinity In Mixed Martial Arts, Stephen L. Swain Jan 2012

Mmasculinities: Spectacular Narratives Of Masculinity In Mixed Martial Arts, Stephen L. Swain

Electronic Thesis and Dissertation Repository

This dissertation uses the work of Guy Debord to examine the Ultimate Fighting Championship, or UFC. More specifically, it examines spectacular narratives surrounding the main event of UFC 114, which featured Quinton ‘Rampage’ Jackson facing ‘Suga’ Rashad Evans. Drawing upon not only the event itself, but also the season of The Ultimate Fighter during which the two combatants coached opposing teams, this study looks at how masculinity is performed and presented, and how those spectacular presentations of masculinity are then used as a means of selling commodities.

Drawing upon the work of Guy Debord, this dissertation examines Mixed Martial Arts ...


Recently Retired Varsity Female Athletes’ Intention To Coach: An Exploration Of Continuity Theory And A Transition-Extension Hypothesis, Erin M. Kodama Jan 2012

Recently Retired Varsity Female Athletes’ Intention To Coach: An Exploration Of Continuity Theory And A Transition-Extension Hypothesis, Erin M. Kodama

Electronic Thesis and Dissertation Repository

The purpose of this study was to examine continuity as an explanation for the intentions of female former athletes to engage in coaching or other roles in sport. In doing so, the study tested the transition-extension hypothesis (Cuskelly, 2004) in the context of former varsity athletes. Eighty-five women (mean age of 23 years; SD = 1.61), who had recently retired from playing their sport within the Canadian Interuniversity Sport (CIS) system, completed an online survey measuring their athletic identity, athletic lifestyle, and intention to engage in coaching and other sport roles. Athletic identity and a sport-related productive lifestyle were most ...


Experiences Of Embodiment: Analysis Of Muslim Women's Participation In Physical Activity, Natalie V.K Szudy Aug 2011

Experiences Of Embodiment: Analysis Of Muslim Women's Participation In Physical Activity, Natalie V.K Szudy

Electronic Thesis and Dissertation Repository

This dissertation examines the relationship the „lived body‟ experiences of veiled Muslim females in sport and physical activity. When considering the relationship between religious requirements and participation in sport and physical activity, the discussion of the conflicts that have occurred with some veiled Muslim female athletes can support the examination of the articulation of sport and religion. In this dissertation, I will explore the application of logical and philosophical discussion as an analytic framework in the evaluation of social, cultural and religious discourse. The application of this framework will contribute to the evaluation of epistemological premises that have contributed to ...


Effects Of Acute Synchronous Whole-Body Vibration Exercise, Tom J. Hazell Dec 2010

Effects Of Acute Synchronous Whole-Body Vibration Exercise, Tom J. Hazell

Electronic Thesis and Dissertation Repository

Recently, whole-body vibration (WBV) exercise has been gaining interest in the health/fitness community for its reported beneficial outcomes. However, most of these have not been evaluated scientifically leading to some reservation in promoting this new exercise modality. The purpose of this dissertation was to assess the viability of WBV exercise to enhance several selected indices of health.

Study 1 demonstrated that the addition of WBV to an isometric semi-squat in young healthy men (n = 8, 25±2.6 y, 177±7.0 cm, 84±12.1 kg) resulted in increases in femoral artery blood flow and leg skin temperature ...


Mental Blocks: The Behavioural Effects And Neural Encoding Of Obstacles When Reaching And Grasping, Craig S. Chapman Nov 2010

Mental Blocks: The Behavioural Effects And Neural Encoding Of Obstacles When Reaching And Grasping, Craig S. Chapman

Electronic Thesis and Dissertation Repository

The ability to adeptly interact with a cluttered and dynamic world requires that the brain simultaneously encode multiple objects. Theoretical frameworks of selective visuomotor attention provide evidence for parallel encoding (Baldauf & Deubel, 2010; Cisek & Kalaska, 2010; Duncan, 2006) where concurrent object processing results in neural competition. Since the end goal of object representation is usually action, these frameworks argue that the competitive activity is best characterized as the development of visuomotor biases. While some behavioural and neural evidence has been accumulated in favour of this explanation, one of the most striking, yet deceptively common, demonstrations of this capacity is often overlooked; the movement of ...