Kinesiology Commons^™

The Effect Of Loading Rate On Annulus Fibrosus Strength Following Endplate Fracture, John Mcmorran

Theses and Dissertations (Comprehensive)

Low back pain is the most prevalent cause of chronic pain for North Americans, and its correlation with endplate damage, and deficient mechanical properties in the annulus fibrosus (AF) makes this injury particularly concerning. To date, biomechanical alterations in the AF following endplate fracture have not been well described. Owing to the AF’s collagenous composition, and the intrinsic biomechanics of intervertebral discs (IVDs) during compression, it was hypothesized that the mechanical properties of AF specimens would show rate-dependent alterations in their tensile and adhesive strengths following endplate fracture. The purpose of the present study was to quantify the mechanical properties …

Exploring Psychological Readiness To Return To Sport After Injury, Scott Donald

Theses and Dissertations (Comprehensive)

Athletes are often cleared to return to sport with little emphasis on psychological readiness in relation to physical readiness. This is important because athletes who are not psychologically ready to return to sport (RTS), despite being physically cleared, may lack motivation to compete and lack confidence in their abilities (Podlog, Banham, Wadey, & Hannon, 2015), drop out of sport, fear re-injury (Ardern et al., 2014), worry about future performance (Podlog & Eklund, 2006), experience anxiety and feel depressed (Tracey, 2003) or incur further injury (McCullough et al., 2012). Remarkably, there is no definition of psychological readiness consistently used in the …

Physical Fatigue Negatively Affects Decision-Making During A Closing-Gap Aperture Crossing Task When Using Joystick-Controlled Locomotion, Natalie Snyder

Theses and Dissertations (Comprehensive)

Goal-direct locomotion is made possible through the integration of sensory input from the visual, vestibular, and somatosensory system. However, changes in collision avoidance behaviours and action capabilities (i.e., affordances) may occur when a sensory conflict is introduced (i.e., via incongruent input from a sensory system). Further, changes to the person (such as physical fatigue) may have negative implications on the cognitive abilities of an individual following physically fatiguing exercise. This in turn could affect an individual’s ability to avoid collisions with objects or other individuals in their environment. Thus, the objective of this thesis was to explore how physical fatigue …

The Task At Hand: Fatigue-Associated Changes To Corticospinal Excitability During Writing, Kezia Cinelli

Theses and Dissertations (Comprehensive)

Corticospinal excitability as measured via transcranial magnetic stimulation (TMS) is highly dependent on the task being performed at the time of stimulation. As such, this study sought out to measure corticospinal excitability during the relevant, daily task of writing and compare it to the conventional abduction task often utilized. We used single-pulse motor evoked potentials (MEPs) to provide a measure of corticospinal excitability and cortical silent period (CSP) duration, and paired-pulse conditioned MEPs to assess short-interval intracortical inhibition (SICI) and intracortical facilitation (ICF) recorded from the right first dorsal interosseous (FDI) of 19 participants on two randomized and counter-balanced days. …

Spinal Motor Neuron Excitability During Fatigue, Nathalie Cecire

Theses and Dissertations (Comprehensive)

Fatigue during sustained or repeated muscular contractions can be from contractile failure within the muscle or reduced excitability in the supraspinal and spinal motor neurons. However, spinal motor neurons can also compensate for fatigue. We speculate that one way the spinal motor neuron compensates for fatigue is through an increase in excitability via the activation of persistent inward currents (PIC). In other conditions where there is a reduction in descending drive, such as during spinal cord injury and aging, there are adaptions of the spinal motor neurons to have elevated PIC amplitudes or towards a greater prevalence of PIC, respectively. …

Exploring The Potential Neuromuscular Adaptations Associated With Sprint Interval Training, Samer Hassan

Theses and Dissertations (Comprehensive)

Purpose. The primary purpose of this study was to explore the acute (a single sprint interval training or SIT exercise session) and chronic (3 weeks of SIT) neural adaptations that may occur with the SIT (30 second sprint and 4 minutes of rest).

Methods. 28 recreationally active participants were pseudo-randomized into either a control group (CTRL) or training group (TR) and tested at 4 time points after baseline VO_2max testing. Participants were tested, pre-training/pre-fatigue, pre-training/post-fatigue, post-training/pre-fatigue, post-training/post-fatigue. The fatigue protocol was a SIT session (4 x 30-s sprints). The TR completed a 3-week running SIT protocol (3x/wk) progressing …

The Relationship Between Caregiver Burden And Depressive Symptoms In Ontario Home Care Clients, Nicole Williams, Samantha Jamal, Dawn M. Guthrie

Health Sciences Faculty Publications

The onset of depressive symptoms is common in home care clients and their caregivers. Understanding the experience of the informal caregiver can assist clinicians in providing services to maximize the well-being of both the client and their caregivers. The objectives of this article are to examine risk factors for the development of depressive symptoms. A longitudinal analysis design was completed for clients with 2+ assessments. The development of depressive symptoms was defined as a Depression Rating Scale score of 3+ on re-assessment. The results-overall, 10.7% of clients experienced new depressive symptoms and clients with a caregiver who was feeling distressed, …

A Deterioration In Hearing Is Associated With Functional And Cognitive Impairments, Difficulty With Communication And Greater Health Instability, Nicole Williams, Dawn M. Guthrie, Jacob G.S. Davidson, Kathryn Fisher, Lauren E. Griffith

Health Sciences Faculty Publications

Objectives: To examine the relationship between hearing deterioration and several health-related outcomes among home care clients in Ontario. Design: Longitudinal analysis was completed for clients with at least two comprehensive assessments. Hearing status, based on a single item, ranged from zero (no impairment) to three (highly impaired). Hearing deterioration was defined as at least a 1-point decline between subsequent assessments. Results: Seven percent experienced a 1-point deterioration in hearing and roughly 1% had a 2/3-point decline. After adjusting for other covariates, increasing age (odds ratio = 1.94; 95% confidence intervals [CIs] = [1.45, 2.61]) and a diagnosis of Alzheimer's disease …

Combined Impairments In Vision, Hearing And Cognition Are Associated With Greater Levels Of Functional And Communication Difficulties Than Cognitive Impairment Alone: Analysis Of Interrai Data For Home Care And Long-Term Care Recipients In Ontario, Dawn M. Guthrie, Jacob G.S. Davidson, Nicole Williams, Jennifer Campos, Kathleen Hunter, Paul Mick, Joseph B. Orange, M. Kathleen Pichora-Fuller, Natalie A. Phillips, Marie Y. Savundranayagam, Walter Wittich

Health Sciences Faculty Publications

Objectives: The objective of the current study was to understand the added effects of having a sensory impairment (vision and/or hearing impairment) in combination with cognitive impairment with respect to health-related outcomes among older adults (65+ years old) receiving home care or residing in a long-term care (LTC) facility in Ontario, Canada.

Methods: Cross-sectional analyses were conducted using existing data collected with one of two interRAI assessments, one for home care (n = 291,824) and one for LTC (n = 110,578). Items in the assessments were used to identify clients with single sensory impairments (e.g., vision only [VI], hearing only …

Exploring The Relationship Between Group Cohesion And Compassion In Varsity Athletes, Theo Chu

Theses and Dissertations (Comprehensive)

Compassion is a prosocial behaviour characterized by kindness and a non-judgmental attitude to reduce one’s suffering. Typically, it is thought of as a behaviour we express outwardly to others, but compassion can also be directed internally toward ourselves. This is known as self-compassion. The benefits of having compassion for other people have been largely studied in employment settings and everyday life behaviours. Moreover, research has shown self-compassion is also related to many positive outcomes. Compared to compassion for others, self-compassion has been studied in sport, however it is still in its infancy. Although research has demonstrated the importance of both …

The Sidewalk Problem: An Examination Of The Avoidance Behaviours Employed During A Head-On Collision Course With An Approaching Person, Lana M. Pfaff

Theses and Dissertations (Comprehensive)

Individuals use visual information in order to guide their avoidance behaviours. More specifically, individuals may directly perceive the time prior to colliding with an approaching obstacle (i.e., time to contact, TTC) in order to determine when to avoid. However, if the path of the approaching obstacle is highly predictable, individuals do not use a consistent TTC (Cinelli & Patla, 2007). Additionally, individuals use body- and action-scaled information to control their movements (Fajen, 2013). These avoidance behaviours differ when avoiding a human obstacle compared to an inanimate object (Hackney, Cinelli, & Frank, 2015; Knowles, Kreuser, Haas, Hyde, & Schuchart, 1976). As …

Examining The Effects Of Interleukin-6 On Appetite Regulatory Peptides In Lean And Obese Sedentary Males, Greg L. Mckie

Theses and Dissertations (Comprehensive)

Acute moderate-intensity exercise transiently suppresses appetite via fluctuations in the appetite-regulatory peptides acylated ghrelin (AG), peptide tyrosine-tyrosine_3-36 (PYY_3-36), and active glucagon-like peptide-1 (GLP-1). Importantly, these effects do not lead to compensatory changes in energy intake in normal weight or obese individuals, highlighting the potential for exercise to induce acute energy deficits. One potential mechanism for these effects is increased post-exercise plasma concentrations of interleukin (IL)-6, as IL-6 has demonstrated appetite-inhibitory effects in animal and cell culture models. Given obesity is characterized by a state of chronic low-grade inflammation and associated with upregulated IL-6, this study sought to …

Sprint Interval Training: Assessing Effectiveness And Adherence In A Real-World Setting, Gregory Howe

Theses and Dissertations (Comprehensive)

Introduction: Perceived lack of time is an oft-cited reason for not engaging in physical activity. One proposed solution is high-intensity interval training (HIIT), or a more intense version known as sprint interval training (SIT), which involves repeated “all-out” efforts interspersed with short recovery periods. Although convincing evidence demonstrates the efficacy of SIT on cardiorespiratory fitness and other health factors, whether individuals will independently perform and benefit from this type of exercise outside the supervised lab setting is unknown. Purpose: To compare the effectiveness and adherence of performing running SIT and moderate-intensity continuous training (MICT) protocols in a real-world setting. Methods: …

Exploring Lactate’S Role In Appetite Regulation Following High-Intensity Exercise, Luke W. Vanderheyden

Theses and Dissertations (Comprehensive)

Background: Intense-exercise has demonstrated an appetite suppressing effect post-exercise, however the involved mechanisms are not well understood. Lactate appears to be one viable mechanism as it has been found to bind to receptors on acylated ghrelin to inhibit release in cell culture. As sodium bicarbonate (NaHCO₃) can alter lactate accumulation post-exercise without manipulating exercise-intensity, it presents an intriguing means to investigate lactate’s potential role. Purpose: To examine the role of lactate on appetite using NaHCO₃ to alter blood lactate concentrations during high-intensity exercise. Methods: Eight recreationally active males completed two identical exercise sessions of low-volume high-intensity interval …

Differences In Perceptions Of Aperture Crossing During A Virtual Reality Choice Reaction Task Between Non-Athletes And Varsity Athletes, Jaime Mitchell

Theses and Dissertations (Comprehensive)

Background: Vision will guide the actions and behaviors that allow us to circumvent environmental obstacles. When passing through a gap, individuals will consistently elicit a shoulder rotation (SR) if the gap is 1.4 times their shoulder width (SW) or narrower, with this behaviour being produced under various environmental conditions. Although a few studies have investigated perceptual predictions regarding gap passage, the effect of physical activity and the differences between trained and untrained athlete’s behaviours has not been examined. This study investigated the perceptual judgements of non-athletes and varsity athletes regarding the action they would utilize to pass through a dynamically …

A Comparison Of The Stability & Pressure Distribution Between Young Adults And A Transtibial Amputee During Obstacle Crossing, Colin Kirst

Theses and Dissertations (Comprehensive)

Falls are identified as the largest risk and leading cause of injury for multiple populations, including young adults and individuals with a transtibial amputation. Furthermore, obstacle crossing is identified as the number one cause of a trip, which subsequently leads to falling. Previous research provides conflicting results and a lack of specificity in certain outcome measures of dynamic stability during obstacle crossing. Therefore, the purpose of this thesis was to gain foundational knowledge on outcome measures related to dynamic stability during an obstacle crossing protocol. An additional purpose was to investigate the dynamic stability of young adults, and speculate on …

The Fatigue-Associated Changes In Estimates Of Persistent Inward Current In Human Motor Neurons, Chris Compton

Theses and Dissertations (Comprehensive)

Neuromuscular fatigue is associated with reduced supraspinal drive. Similarly, intracortical facilitation and muscle activation are reduced following concussion. Both fatigue and mild traumatic brain injury are associated with increased noradrenergic and serotonergic activity in animal models. Given that monoaminergic-dependent persistent inward currents (PIC) set spinal motor neuron (MN) gain, we speculate that PIC will increase during fatigue to compensate for supraspinal hypoexcitability and that this will be more pronounced in people with concussion. Therefore, the purpose of this experiment was to assess spinal MN excitability during fatigue in people with concussion and healthy controls. 20 participants (10 concussion, average age …

The Effectiveness Of Teamwork Training On Teamwork Behaviors And Team Performance : A Systematic Review And Meta-Analysis Of Controlled Interventions, Desmond Mcewan, Geralyn R. Ruissen, Mark Eys, Bruno D. Zumbo, Mark R. Beauchamp

Kinesiology and Physical Education Faculty Publications

The objective of this study was to conduct a systematic review and meta-analysis of teamwork interventions that were carried out with the purpose of improving teamwork and team performance, using controlled experimental designs. A literature search returned 16,849 unique articles. The meta-analysis was ultimately conducted on 51 articles, comprising 72 (k) unique interventions, 194 effect sizes, and 8439 participants, using a random effects model. Positive and significant medium-sized effects were found for teamwork interventions on both teamwork and team performance. Moderator analyses were also conducted, which generally revealed positive and significant effects with respect to several sample, intervention, and measurement …

Task-Dependent Modulation Of Cortical Excitability And Balance Control In Individuals With Post-Concussion Syndrome, Kristen Kaster, Jayne M. Kalmar Ms., Michael E. Cinelli Mr

Theses and Dissertations (Comprehensive)

In most cases, symptoms resolve between 7-10 days post-concussion. However, in 10-15% of the concussed population, symptoms can remain unresolved for months to years following the head injury. The purpose of this thesis was two-fold, and was broken up into two studies, where the same individuals participated in both studies. The purpose of the first study was to quantify the differences in balance control between individuals with PCS (i.e., had been experiencing symptoms for <30 days) and non-concussed individuals during a lower-limb reaching task. Participants completed a static balance assessment before and after a lower-limb reaching task, which incorporated a Go/No-Go paradigm. Results from this study revealed no differences in the static stability assessments, however, individuals with PCS demonstrated increased medial-lateral COP displacement as well as greater trunk pitch during the reaching task. Overall, the findings reveal persistent balance impairments in individuals with PCS, which may put this population at an increased risk of further injury. The purpose of the second study was to assess task-dependent modulation of cortical excitability prior to planned index finger abduction contractions comparing a non-concussed population to a population with PCS. The protocol in this study consisted of both single and paired-pulse transcranial magnetic stimulation (TMS) which was applied prior to the beginning of 3 different tasks (i.e., a rest condition with no plan to contract, a precision contraction, and a powerful contraction). In addition to the three tasks, participants also had to respond to a Go/No-Go cue. The results of this study revealed an increase in excitability prior to a precision contraction in both non-concussed and PCS groups. No differences in task-dependent modulation were found between the two groups with respect to intracortical facilitation and inhibition, however a negative correlation between number of symptoms reported (SCAT3 symptom evaluation) and intracortical facilitation was revealed. The increase in corticospinal excitability prior to a precision contraction was not explained by the two cortical mechanisms we assessed and may therefore be due to spinal modulation or a different cortical mechanism. Overall, based on the results from this thesis, it appears that individuals with PCS have balance impairments, which may be a result of an inability to maximally activate their postural muscles. Furthermore, it appears that those individuals who reported a higher number of symptoms had greater reductions in intracortical facilitation, likely reflecting the heterogeneity of this clinical group.

The Effects Of A 12-Week Custom Foot Orthotic Intervention On The Intrinsic Muscles Of The Foot, And Dynamic Stability During Unexpected Gait Termination In Healthy Young Adults, Katrina Protopapas

Theses and Dissertations (Comprehensive)

Introduction: Custom-made foot orthotics (CFO’s) are a commonly prescribed intervention to help individuals that are suffering from foot pain and foot disorders. However, the mechanisms of CFO’s are still poorly understood and are not well known. With the plantar intrinsic muscles of the foot being in direct contact with the CFO, it puts these structures at risk for disuse muscle atrophy as a result of being offloaded. Therefore, the purpose of the current study was to determine the effect of a 12-week custom-made foot orthotic intervention on the intrinsic muscles of the foot and dynamic stability during unexpected gait termination. …

Peripheral Visual Motion Sensitivity In Previously Concussed, Asymptomatic Individuals, Alyssa Prangley

Theses and Dissertations (Comprehensive)

Background: Individuals acquire information about self-motion from the environment which specifies actions necessary to be successful (Fajen & Matthis, 2011). However, concussed individuals demonstrate residual disturbance in execution of postural movement at 30 days post injury, depicting an impaired ability to perceive self-motion in a visually conflicting environment (Slobounov et al. 2006). The objective of this thesis was to investigate the extent to which one’s behaviours on a central field of view task are influenced by the amount and type of peripheral visual movement during a collision avoidance task, as well as to determine the additive effects of changes to …

The Experiences Of Athletes, Parents, And Coaches With The Long-Term Athlete Development Model (Ltad) In Youth Soccer Academies, Kody Watson

Theses and Dissertations (Comprehensive)

The Long-Term Athlete Development Model (LTAD) has been developed to allow children the best chance of engaging in lifelong sport and physical activity. The LTAD focuses on long-term development, not short-term success, which allows for the best opportunity of sport participation and optimal sport potential throughout life (Balyi, Way, & Higgs, 2013). Research surrounding the LTAD model has stated that there is a lack of empirical evidence of the model being utilized within sport, as some researchers believe that it is more theoretical than practical (Lloyd & Oliver, 2012). However, even with this criticism of the LTAD model, Canadian sport …

Sedentary Behaviour, Physical Activity, And Mobile Apps Among University Students, Emily E. Dunn

Theses and Dissertations (Comprehensive)

Prolonged sedentary behaviour (SB) poses health risks independent of physical activity (PA) levels (Owen et al., 2010). University students in particular are at risk of engaging in prolonged SB due to the demands of school. Due to the pervasiveness of smartphones, and ability of mobile applications (apps) to target SB (Bond et al., 2014), apps may be used to encourage less SB in this population. Apps for PA have been coded for behaviour change techniques (BCTs) (Conroy et al., 2014; Middelweerd et al., 2014; Yang et al., 2015), however, apps for SB have yet to be assessed for BCTs.

The …

An Investigation Of The Relationship Between Intervertebral Disc Puncture, Inflammation, And Tissue Mechanics Using A Rat-Tail Model., Brigitte Laird

Theses and Dissertations (Comprehensive)

Introduction: The intervertebral disc (IVD) is composed of the annulus fibrosus (AF), which surrounds and contains the nucleus pulposus (NP). It is hypothesized that when the IVD becomes injured, in the case of IVD herniation, a localized innate immune response is initiated. Although the presence of pro-inflammatory cytokines in injured IVDs has been well documented, the extent to which inflammation affects the mechanical properties of the IVD remains poorly understood. The purpose of this study was to determine the effect of IVD damage (via puncture) and inflammation (via lipopolysaccharide (LPS) exposure) on the mechanical and structural properties of the IVD. …

An Evaluation Of Older Adults’ Perceptions Of Psychological Well-Being When Participating In Community Centre Programs, Kayla Rellinger

Theses and Dissertations (Comprehensive)

Multi-purpose organizations, such as community centres, provide opportunities for individuals to participate in various physical and social activities. Although, it has been well established that community centres provide the opportunity and environment to promote health behaviour changes among older adults (Jones et al., 2013; Stewart, 1997; Wallace et al., 1998), there is a dearth of research differentiating between physically active and non-active community centre programming. The purpose of the current study was to evaluate whether participating in community centre programming influenced four key measures of perceived psychological well-being, as well as, to evaluate whether the perceived psychological well-being of community …

The Effects Of Orthotics And Increased Plantar Sole Mechanoreceptor Activation On Turning Performance In Individuals With Parkinson’S Disease, Kelly A. Robb

Theses and Dissertations (Comprehensive)

Locomotion and turning are complex movement patterns essential to activities of daily living. Individuals with Parkinson’s disease (PD) report difficulties turning, often coupled with impaired balance and increased fear of falling. The purpose of this within-subject study was to determine if orthotics, with and without a textured top cover, can improve gait stability and turning performance within Parkinson’s participants. Seven participants with a diagnosis of idiopathic Parkinson’s disease, aged 55-80 years old, participated in the study. Participants completed three testing sessions; baseline, 4 weeks post-baseline, and 5 weeks post-baseline. The ‘footwear only’ and ‘footwear + non-textured orthotic’ conditions were tested …

The Effects Of External Focus Of Attention Exercise Rehabilitation On Dual Task Walking In Parkinson's Disease, Eric N. Beck

Theses and Dissertations (Comprehensive)

Parkinson’s disease impairs control of well-learned movements, and therefore, individuals with Parkinson’s disease are forced to walk with greater conscious control. This causes difficulties while walking and completing a secondary task simultaneously (dual tasking), in that distractions from conscious control of walking increase the risk of falls and injury. Although, attention-based exercise may be a potential avenue to decrease the demands associated with walking in Parkinson’s disease. For example, an external focus of attention (on manipulated objects) has been found to recruit the networks that are important for walking with little conscious control (automatic control networks). In contrast, an internal …

The Influence Of Joint-Site, Limb Preference, And Physical Activity On Joint Position Sense, Amanda N. Forsyth

Theses and Dissertations (Comprehensive)

Joint position sense provides the body with information about where limb segments are relative to one another in three-dimensional space. The ability to utilize this sense is imperative for smooth, coordinated, and accurate movement in everything from activities of daily living to competitive sport (Ghez & Sainburg, 1995). Researchers currently use joint position sense as a measure of proprioceptive acuity. However, limited research has investigated the influence of potential confounding factors on proprioception. Specifically, literature on how joint-site specificity and lateral preference influence proprioception displays several incongruent findings. Therefore, the purpose of the current study was (1) to determine if …

Estimates Of Persistent Inward Current Decline In Human Soleus Motor Units During Fatigue, Kirby Mendes

Theses and Dissertations (Comprehensive)

Fatigue is defined as any exercise induced reduction in strength or power, and can be attributed to central and peripheral components. Many central and peripheral mechanisms have been extensively studied, but few studies have looked at the changes in the intrinsic properties of motor neurons and their contribution to fatigue. Persistent inward current (PIC) is an important intrinsic property of motor neurons responsible for setting a large increase in the gain of motor output and may contribute to fatigue. Inhibitory inputs such as reciprocal inhibition (RI) have been shown to turn off PICs and reducing the gain of output. PIC …

The Bigger Picture: Piecing Together The Experiences Of Family Members Living With High-Functioning Children With Autism Spectrum Disorder, Lauren Thomson

Theses and Dissertations (Comprehensive)

The purpose of this research was to explore the experiences of family members living with a child with ASD. The specific research questions that were addressed included: 1. How is a family member affected by having a child with ASD in the family unit; and 2. How does living with a child with ASD affect family functioning? The theoretical orientation of phenomenology was used to guide this research and to allow the “voice” of family members of children with ASD to be heard. The purpose of phenomenology is to distill individuals’ experiences with a phenomenon down to an “essence” of …