Kinesiology & Health Science

Permanent URI for this collectionhttps://hdl.handle.net/10315/27572

Browse

Now showing 1 - 20 of 437

Access status: Open Access ,
Indigenous Health Counts: Advancing Meta-Analysis Methods for Respondent-Driven Sampling and First Nations, Inuit, and Metis Peoples Living in Urban Areas in Ontario
(2025-11-17) Octavia Chi Yan Wong; Rotondi, Michael
Introduction: There is a lack of accurate and valid health information for First Nations, Inuit, and Métis (FNIM) peoples living in urban areas in Canada. Respondent-driven sampling (RDS) is a statistical and sampling technique that allows the health of Indigenous peoples living in urban areas to be examined through the use of their social networks. There are currently no techniques available to pool the results of RDS studies to obtain overall summary-level information across RDS samples. The objective of this dissertation was to develop a meta-analysis technique for RDS data and examine the combined, overall prevalence of key outcomes identified by local Indigenous health service organizations. Data were obtained from the community-led Our Health Counts (OHC) projects – five Indigenous health studies which successfully applied RDS in the cities of Hamilton, Toronto, London, Kenora, and Thunder Bay. Primary outcomes include diabetes mellitus (DM), prescription opioid (PO) use without a prescription or in unprescribed ways, experiences of discrimination in the healthcare system, and use of traditional medicines. Methods: Four manuscripts were completed, including one simulation study and three applications of the results of the simulation study. The first study developed and validated preliminary meta-analysis methods for random effects (RE) and fixed effects (FE) models for RDS data. The subsequent three manuscripts examine the prevalence of (1) DM, (2) PO use without a prescription or out of keeping with the prescription, and (3) experiences of anti-Indigenous discrimination in the healthcare system and use of traditional medicines in FNIM peoples living in urban areas through RE meta-analysis. Results: Using the average variance calculated from RDS-II bootstrap confidence intervals as the estimate of within-study variance for RE and FE models was the only valid meta-analysis method for RDS data. For younger adults, the prevalence of DM was higher among FNIM peoples living in Ontario cities compared to the general population. FNIM peoples living in cities also had a higher prevalence of PO use without a prescription or in unintended ways than the general population. Age differences were found in the prevalence of experiences of anti-Indigenous discrimination in the healthcare system by FNIM peoples living in cities, with younger people reporting more discrimination. Conclusion: RDS is a valuable sampling and statistical technique for examining the health of FNIM peoples living in urban areas in Ontario. Pooling data across OHC sites allows us to obtain a more precise, overall understanding of priority outcomes identified by the Indigenous community partners. Improved understanding allows community partners and decision makers actionable information to tailor programs and interventions to support the needs of Indigenous peoples and to be more effective in improving equity in the healthcare system.
Access status: Open Access ,
Cellular Stress and Effects on Mitochondrial DNA: An Assessment of Stress Reduction & Protective Effects
(2025-11-11) Tiwana, Jasmin Kaur; Ritvo, Paul G.
Introduction: Psychological stress results in energy demands and changes in the mitochondria that produce 90% of bodily energy as adenosine triphosphate (ATP). Cell-free mitochondrial DNA (cf-mtDNA) is released into the bloodstream under stress which was induced with the International Affective Picture System (IAPS). We hypothesized that participants exposed to mindfulness meditation (MM) instruction would demonstrate lesser increases in cf-mtDNA levels and negative mood states compared to controls. Methods: Thirty-five females (18-30 years) were randomized to an experimental group (MM) or a control group (educational podcast). Both groups viewed IAPS images, completed questionnaires and two blood draws. Results: A paired samples t-test revealed no significant differences in cf-mtDNA levels from pre- to post- IAPS stress exposure between groups. Conclusion: This randomized controlled trial is the first study to explore the potentially protective effects of MM on cf-mtDNA levels and mood after an acute lab stressor. No statistically significant results were found.
Access status: Open Access ,
Anti-Obesity Pharmacotherapy-Induced Loss of Muscle Mass and Function is Rescued by Modulating Dietary Protein Consumption in a Model of Childhood Obesity
(2025-11-11) Morris, Brooke Ally; Perry, Christopher G, R.
Pharmacological treatment options for obesity management, such as glucagon-like peptide-1 receptor agonists (GLP-1 RAs), yield significant weight loss. Lean mass accounts for a substantial proportion of weight loss, which is contraindicated owing to the reduced muscular mass and quality that presents in obesity, and may have particular implications in an adolescent model. This study determined the effect of semaglutide on body composition, skeletal muscle function, and bone deposition; and whether a protein-enriched dietary intervention could prevent negative effects of semaglutide on musculoskeletal health. Semaglutide treatment led to lower bodyweight, muscle mass, and maximal contractile function in adolescence, but did not affect submaximal contractile or mitochondrial function. Semaglutide improved load-bearing bone volume. Protein supplementation was able to restore bodyweight, muscle mass, and contractile function when used with semaglutide. This study reveals the effects of semaglutide on muscle health in an adolescent obesity model and presents protein supplementation as a viable solution.
Access status: Open Access ,
Twenty-Year Trends in the Prevalence and Predictors of Healthcare Provider Advice to Lose Weight: U.S. NHANES, 1999-2018
(2025-11-11) Gao-Kang, Jenny; Ardern, Chris
Healthcare providers (HCP) play a critical role in screening for obesity and supports for obesity management. We examined 1999–2018 trends in the prevalence and predictors of U.S. adults being told to lose weight using ten nationally representative NHANES cycles (n=16,424). Survey-weighted descriptive statistics and multivariable logistic regression identified sociodemographic, anthropometric (BMI, WC), clinical (MetS, EOSS), and behavioral predictors stratified by age, sex, and ethnicity. Overall, 34.4% reported ever receiving weight-loss advice; the prevalence rose from 11.1% to 19.2% among overweight and from 20.9% to 33.4% among obese individuals. Adjusted models showed older age, female sex, higher BMI (OR overweight = 6.15; obese = 41.86), elevated WC (OR = 8.37), and EOSS stages 2 (OR = 3.90) and 3 (OR = 5.07) were strong independent predictors, while socioeconomic and behavioral factors were modest. HCP weight-loss advice increased over two decades but remains predominantly driven by simple anthropometric measures; integrating comprehensive clinical risk tools like EOSS may improve equitable obesity care.
Access status: Open Access ,
The Acute Effects of Greek Yogurt Consumption on Circulating Bone Metabolic Markers Following High-Intensity Cycling in Premenopausal Females with Overweight and Obesity
(2025-11-11) Gagnon, Sara; Josse, Andrea
This thesis compared the bone turnover and metabolism responses of post-exercise Greek yogurt (GY) consumption and an isoenergetic carbohydrate pudding (CP) following high-intensity interval cycling (HIIC) in young- to middle-aged inactive premenopausal females with overweight and obesity. We hypothesized that GY would attenuate post-exercise bone resorption and/or amplify formation compared to CP. Using a randomized crossover design, participants completed an acute HIIC bout followed by the consumption of either GY or CP. Blood samples were collected at pre-exercise, post-exercise, 1hr and 3hr postprandially, and 24hr post-exercise. Bone turnover and metabolism markers RANKL, OPG, PTH, OPN, CTX, SOST, OC, and IGF-1 were measured from serum. Interactions were observed whereby OPG and OC were higher at 1hr and 3hr postprandially, respectively, and PTH was lower throughout the postprandial period in GY versus CP. Thus, GY consumption favourably modulated the acute post-exercise bone turnover and metabolism response in these females.
Access status: Open Access ,
Sport Leadership in the Greater Toronto Area Tamil Diaspora: Exploring the Lived Experience of Sport Leaders in Tamil Grassroots Sports Organizations
(2025-11-11) Sriranganathan, Gobika; Nakamura, Yuka
Civil war in Sri Lanka precipitated the mass emigration of Tamils from Sri Lanka in the 1980s, many of whom settled in the Greater Toronto Area (GTA). This community has since established significant social support networks and cultural infrastructure including, and of interest to this study, a growing number of Tamil grassroots sports organizations. Specifically, this study investigates the experience of leaders in the GTA Tamil diasporic sport community. The research objectives are to: 1) document the experiences of Tamil sport leaders in the GTA that led to their involvement with Tamil sport leagues; 2) understand what sport leadership means within the Tamil sporting community; 3) understand the gendered and gendering nature of sport leadership; and, 4) identify potential barriers that Tamils, in particular Tamil women, experience in sport leadership and strategies to negotiate them. Postcolonial feminism and intersectionality theory inform this study to allow for deeper understanding of the impact colonialism has had on the Tamil diaspora and exploration of the meaning and consequences of multiple interacting social identities, such as class, race, gender and other systems of unequal power on sport leadership within the community. An exploratory multiple case study approach is used in this study to allow for intensive study of sport leaders through interviews and social media analysis. By exploring the lived experiences of second and 1.5 generation Tamil sport leaders in the GTA, the importance of diasporic identity, gender norms, and postcolonial dynamics in shaping Tamil grassroots sports leadership is revealed. A hybrid leadership model emerges that has roots in both Tamil and Western ideologies as sport leaders navigate a ‘third space’ in the sporting sphere. Tamil women must also navigate intersecting barriers and supports at individual, interpersonal, organizational and cultural levels, adopting strategies such as collective leadership, which underscores the complex, gendered nature of leadership in diasporic sporting spaces.
Access status: Open Access ,
'We Can All Make Our Own Choices’: Using a Feminist Participatory Action Research Approach to Explore and Mobilize the Experiences of Athletes in a Girls-Only Community Sport Program
(2025-11-11) Li, Winnie Yung-Yu; Erickson, Karl
To belong is different from being included. Belonging involves feeling like you not only have a voice, but that your voice is being heard and appreciated. This study explored this idea in the realm of youth sport through partnering with a community-based organization that provides sport programming for girls from equity-deserving groups. Utilizing a feminist participatory action research (FPAR) approach and the qualitative method of photovoice, the lived experiences of 4 athletes participating in the organization’s recreational soccer program were captured. Aligning with the action component of FPAR and tenets of knowledge mobilization, their voices were amplified through various mobilization strategies to create actionable social impact and better ensure the participants felt heard by people who play a role in shaping their sporting experiences. Overall, the findings demonstrate the value of listening and learning from a diverse set of voices in the development, delivery, and evaluation of youth sport programming.
Access status: Open Access ,
Resting Microvascular and Autonomic Function in Relation to Age and Sex Hormone Concentrations
(2025-11-11) Gujral, Mankirat Kaur; Edgell, Heather
This study assessed the influence of estradiol, progesterone, testosterone and age on resting microvascular and autonomic function in younger and older males and females. Microvascular function was assessed with reactive hyperemia using the microvascular function index (MFI) technique (5mins baseline, circulatory occlusion and reperfusion) and was calculated using the area under the curve of pulse waveforms before and after occlusion/reperfusion. Autonomic function was assessed using 5 mins resting heart rate variability (HRV) and paced deep breathing. Multiple linear regressions were conducted for the influence of estradiol, progesterone, testosterone and age on resting HRV variables and MFI. Aging negatively correlated with respiratory sinus arrhythmia (RSA) indicating lower parasympathetic activity and positively correlated with diastolic blood pressure (DBP) and mean arterial pressure (MAP). Estradiol positively correlated with the low frequency/high frequency ratio of HRV, indicating higher sympathetic activity, and DBP and MAP. Progesterone and testosterone were not significantly correlated with any measures.
Access status: Open Access ,
Differential BCAA Metabolism in Tissues of Tumor-Bearing Mice: A Path to Understanding Cancer Cachexia
(2025-11-11) Zerrouk, Miriam; Adegoke, Olasunkanmi A. J.
Cancer cachexia is a complex syndrome marked by muscle and fat loss, often resistant to nutritional support. While branched-chain amino acids (BCAAs) stimulate muscle protein synthesis, BCAA-targeted therapies have shown inconsistent results. In this study, a C26 colon cancer mouse model was used to examine how tumor burden alters BCAA metabolism across skeletal muscle, liver, kidney, and adipose tissue. Tumors accumulated BCAAs and showed increased enzymatic activity, whereas peripheral sites displayed widespread BCAA depletion, reduced expression of the amino acid transporter LAT1, and suppression of mechanistic target of rapamycin complex 1 (mTORC1) signaling. Notably, the soleus muscle maintained mTORC1 activity despite reduced BCAA availability, suggesting fiber-type–specific adaptations. These findings indicate that tumors act as metabolic sinks, diverting systemic amino acids away from host tissues. Such reprogramming may underlie the limited success of BCAA-based interventions in cachexia and highlight the need for therapies that address both tumor and host metabolism.
Access status: Open Access ,
Evaluating the Impact of Prescription Drug Coverage on Emergency Department Visits in Youth: Evidence From Ontario's OHIP+ Program
(2025-11-11) Ienciu, Kristine Stephanie; Chum, Anthony
This thesis examines the impact of Ontario’s OHIP+ program (introduced January 2018) to provide prescription coverage to youths <25, on suicide-related behavior (SRB) emergency department (ED) visits among youth. Using interrupted time series (ITS) and comparative ITS (CITS) analyses, the study assessed changes in SRB-related ED visits per 100,000 population overall and by socioeconomic status (SES). Youth with low-SES, less likely to have private insurance and more likely to benefit from OHIP+, were compared to high-SES youth. ITS results showed a significant immediate reduction in SRB-related ED visits after OHIP+ implementation (-9.39, 95% CI: -18.21 to -0.56). CITS results showed a larger immediate decline among low-SES youth (-19.61, 95% CI: -37.71 to -1.50), reducing rates from 54.11 to 45.90 per 100,000, with stronger effects among women. Findings suggest drug coverage can reduce youth mental health crises and support expanded pharmacare.
Access status: Open Access ,
Wheelchair Rugby Classification: A Retrospective Cohort Study Analysis of the Triceps Manual Muscle Test – Comparing Assessed Manual Muscle Testing Scores to Standardized Values
(2025-11-11) McRoberts, Marnie Jaye; Hynes, Loriann M.
This retrospective cohort study evaluated the consistency of triceps manual muscle test (MMT) scores with standardized expectations across low and mid-point wheelchair rugby classifications (0.5–2.5), using data from 492 assessments of 283 Canadian athletes between 1992 and 2019. Athletes were stratified by sport class, and triceps MMT scores were analyzed to determine alignment with standardized ranges. While 0.5 and 2.0 classes showed general alignment, 1.0 and especially 1.5 classes exhibited significant inconsistencies; over 75% of 1.5-class assessments fell outside the expected range. These discrepancies raise concerns about the objectivity, reliability, and application of the modified triceps test within the classification process. The study highlights the influence of contextual factors and subjective judgment in current protocols and underscores the need for greater standardization, improved training, and empirical validation of assessment tools. Refining these elements is essential to ensure fairness, preserve competitive integrity, and uphold the athlete-centered principles of functional classification.
Access status: Open Access ,
"We're the One's Working on the Ground, the 'Real' Ground": Exploring Tensions and Realities of Global South SFD NGOs in Fostering 'Safe Sport' Environments for Children and Youth
(2025-11-11) Iqbal, Isra Shahid; Hayhurst, Lyndsay M.
Across the globe, mounting concerns have been raised about the safety of children and youth in sport (Kerr et al., 2020). As such, many global sport organizations have been implementing safe sport policies and frameworks, such as the International Safeguards for Children in Sport, to protect children and youth from abuse and maltreatment (Gurgis et al., 2022). However, in Global South countries, the implementation of safe sport initiatives remains limited, further complicating efforts to protect children and youth. This study examines the relationship between Sport for Development (SFD) programs and safe sport policies and practices, focusing on how these initiatives support – or fail to support – the safety of children and youth participating in Global South contexts. Grounded in decolonial feminist theory, the study draws on semi-structured interviews with SFD NGO staff members operating in Global South contexts (n = 15) and a documentary analysis of key SFD NGO safe sport policy documents (n = 10). Data was analyzed using two complementary approaches, including Bacchi’s (2012) What’s the Problem Represented to Be (WPR) approach and critical discourse analysis. Findings revealed that safe sport policies and practices must move away from a universal and ‘one-size-fits-all’ approach to safeguarding. Instead, there is a critical need for context-specific safe sport policies that account for local geographies and the sociological, cultural, political, and colonial conditions that shape violence and abuse in Global South regions. To meaningfully enhance the safety of children and youth in SFD programs – particularly in relation to gender, race, and class – further research is needed in the SFD field that prioritizes and foregrounds intersectional and decolonial approaches to safe sport.
Access status: Open Access ,
Effect of Semaglutide on Skeletal Muscle During Weight Loss in Diabetic Rats
(2025-11-11) Taherkhani, Kian; Riddell, Michael C.
Obesity and diabetes mellitus are among the most widespread chronic conditions in modern society. The growing prevalence of obesity has prompted the exploration of various therapeutic interventions, including semaglutide, a glucagon-like peptide-1 receptor agonist (GLP-1RA). GLP-1RAs have shown promise in weight management, but GLP-1 receptors have been found in many tissues beyond the original therapeutic targets (pancreatic beta-/alpha- cells), including skeletal and smooth muscle, heart, and brain. Therefore, it is critical to study the potential effects of GLP-1 on these tissues, as potential off target effects (beneficial or detrimental) are expected. Many aspects or side effects of the medication remain underexplored, including the impact of semaglutide on skeletal muscle mass preservation during weight loss. This thesis investigates the differential effects of semaglutide administration compared to traditional caloric restriction on skeletal muscle mass, insulin signalling and markers of protein turnover in a male rat model of type 2 diabetes (T2D).
Access status: Open Access ,
Understanding Varsity Athlete's Resistance to Sports' Culture of Risk (CoR)
(2025-11-11) Doherty, Calum John; Safai, Parissa
Sport’s “culture of risk” (CoR) normalizes and glorifies playing through pain as a marker of an athlete’s character and commitment. High-profile athletes like Simone Biles and Chris Borland have publicly resisted the CoR by prioritizing their health over participation. Their ability to do so––and to withstand criticism––is enabled, in part, by the capital they enjoy as prolympic athletes. This thesis explores whether (and how) athletes with comparatively less visibility and resources can challenge the CoR’s expectations. Thematic analysis of semi-structured interviews with ten (10) Canadian varsity athletes revealed that participants negotiated competing desires to be both cautious of their health and committed to performance. Ambivalence is used as a conceptual lens to describe this tension, shaped by the forms and limits of participants’ capital. In this sense, ambivalence was not a universal stance, but one made possible by the relative privilege afforded to varsity athletes in Canada
Access status: Open Access ,
Impact of Age at Natural Menopause on Incidence of Immune-Mediated Diseases: Asthma, Hypothyroidism, and Rheumatoid Arthritis in Postmenopausal Canadian Women
(2025-11-11) Kesibi, Durmalouk Rami; Tamim, Hala
The average life expectancy is increasing, and women are now expected to spend more than a third of their lives after menopause. Menopause is marked by major hormonal changes, particularly a significant decline in estrogen levels. Estrogen influences nearly all systems in the body, and an earlier age at menopause (ANM) results in an earlier cessation of estrogen production. Early ANM has been associated with an increased risk of various diseases, while later ANM has been linked to a higher risk of reproductive cancers. However, the relationship between ANM and immune-mediated diseases has not been well studied. Immune-mediated diseases such as asthma, hypothyroidism, and rheumatoid arthritis are more common in women and may be influenced by the timing of menopause. This study retrospectively examined postmenopausal women from the Canadian Longitudinal Study on Aging over a 10-year period. Multivariable Cox regression models were used to investigate the associations between ANM and the incidence of these diseases. The analysis showed that earlier ANM was linked to a reduced risk of asthma, while later ANM was associated with a lower risk of rheumatoid arthritis. No significant association was found between ANM and hypothyroidism. These findings suggest a potentially complex and differential role of estrogen in the immune system. They may inform healthcare professionals in monitoring ANM and evaluating risk for specific immune-mediated diseases. Further research is needed to understand the role of estrogen in the development of these diseases.
Access status: Open Access ,
Effect of Task Error on Implicit Motor Adaptation
(2025-07-23) Rahimpoor-Marnani, Parmin; Henriques, Denise Y. P.
Motor adaptation is essential for maintaining coordination in daily activities. Implicit motor adaptation, operating unconsciously, is primarily considered to be driven by sensory prediction errors. This study aims to investigate how another error signal, task error, affects implicit adaptation across varying perturbation sizes using a visuomotor reaching paradigm. Employing a Single Trial Learning (STL) approach, we compare initial adaptation responses to different target types: a small dot target reinforcing strict spatial accuracy, and a large arc target permitting greater movement endpoint variability. By manipulating target size, we systematically alter task error presence or absence, isolating its influence on implicit motor adaptation, while holding sensory prediction error constant. These findings will advance our understanding of task error and sensory prediction error interactions in the early stages of implicit motor learning. Ultimately, this work aims to refine current motor learning models and inform targeted error type utilization in rehabilitation and training strategies.
Access status: Open Access ,
The Effects Of Dairy Consumption On Bone, Inflammatory, Antioxidant & Metabolic Biomarker Responses To Exercise Or Nutritional Stressors In Humans
(2025-07-23) Prowting, Joel; Josse, Andrea
The overall purpose of this dissertation was to examine the impact of dairy product consumption on outcomes of bone, inflammation, antioxidant & metabolic biomarkers both at rest (Chapter 5) and after exposure to different physiological stressors, including exercise (Chapter 3 & 4) and a high-calorie, high-fat meal (Chapter 6). To achieve this, two human intervention studies (divided into 4 papers) that used different stressors in combination with dairy product consumption were conducted. The collective findings indicate that increased dairy product consumption may confer some benefits to post-exercise bone remodeling and basal circulating inflammatory concentrations but does not have a significant effect on postprandial inflammatory, metabolic or glutathione responses. Therefore, including dairy products as part of a balanced diet could have minor beneficial effects if consumed following impact exercise and/or to potentially ameliorate resting low-grade chronic inflammation in people that may be at higher risk of developing metabolic disease.
Access status: Open Access ,
The Power Of Exercise: The Effect Of Age And Activity Level On Muscular Power
(2025-07-23) Desroches, Daniel Alain; Drake, Janessa D. M.
Muscle, strength, and power decline as we age, and power is critical for functional independence. This dissertation tested additional factors such as the amount and type of PA, muscular fatigue, movement mechanics, and muscle fiber type, which are known to affect power, in older adults, including masters athletes. The study involved PA questionnaires, biomechanical assessment of functional tasks including countermovement jumps (CMJ) with lower-body motion capture and a custom apparatus with embedded force plates, and MRI Dixon and DTI of the lower limb musculature and lumbar spine region. Age, sex and PA level predicted lower-body power during CMJ, with activity level demonstrating a protective effect (r=0.540) similar in magnitude to the effect of age (r=-0.654). Athletics discipline also predicted lower-body power during CMJ (r=0.389) with short distance athletes having the highest predicted power but also the most negative slope. Greater trunk flexion was associated with greater lower-body power, but older adults did not tend to use this strategy. MRI diffusion parameters weakly predicted ankle power and also differed in short distance athletes. Activity level and athletic discipline showed positive, protective effects on lower-body and joint power during the CMJ with a strength of effect comparable to that of age. Trunk flexion angle was associated with greater lower-body power output in the CMJ and was a strategy adopted only by younger adults potentially confounding the measurement of power in older adults. Overall, high levels of PA, and participation in high power track and field events is protective of muscular power and likely functional independence in older adults.
Access status: Open Access ,
Association Of Serum Carotenoids, Non-Alcoholic Fatty Liver Disease, And Metabolic Dysfunctions With All-Cause And Cardiovascular Disease Mortality
(2025-07-23) Sadrmanesh, Omidreza; Kuk, Jennifer L.
Carotenoids are antioxidants associated with a lower mortality risk in the general population. However, the association between mortality and carotenoids among individuals with non-alcoholic fatty liver disease (NAFLD) is still ambiguous. This study aimed to explore the relationship between serum carotenoids with all-cause and cardiovascular disease (CVD) mortality in those with and without NAFLD and metabolic dysfunctions. Using data from the Third National Health and Nutrition Examination Survey, Cox proportional hazard regression models were used to determine the association between serum carotenoids, NAFLD, and metabolic dysfunctions with all-cause and CVD mortality. The results showed that higher total and most individual serum carotenoid levels were associated with a lower risk of all-cause and CVD mortality in those with and without NAFLD and metabolic dysfunctions. NAFLD was independently associated with all-cause mortality, regardless of serum carotenoid levels. However, after adjustment for metabolic dysfunctions, NAFLD was not associated with all-cause mortality.
Access status: Open Access ,
The Effect of Optic Flow During Attention Related Tasks and Quiet Stance
(2025-07-23) Mahnaei, Seyedeh Feryal Feryal; Cleworth, Taylor
Vision plays a significant role in balance as it provides visual cues to help maintain balance. Increasing visual information during upright stance leads to tighter regulation of upright stance. Cognitive related tasks and postural control share capacities and compete for cognitive resources which may cause interference on one or both tasks. There is limited work on the impact of visual gain manipulation on dual tasks that include attention tasks that require visual information while maintaining an upright stance. While previous studies have explored how dual tasks and modified visual feedback influence balance separately, there is limited work on the impact of visual feedback during dual tasks that require visual information. This study explored how visual cues affect balance when combining effects of visual conditions and different cognitive attention tasks. Optic flow was amplified or reduced to 4 gain conditions (0.25x,1x,4x,16x) within virtual reality (VR) relative to the head position while participants stood quietly on a force plate that measure ground reaction forces and completed 12 randomized trials across 3 conditions. Kinematics were collected through 8 markers placed on different parts using motion capture. Muscle activity was also collected by placing EMG on 3 lower leg muscles during the trials. MSRS questionnaire was completed after each trial to assess movement consciousness. Root mean square (RMS), and the mean power frequency (MPF) of Centre of Pressure (COP) and head position (HeadPos) were used to quantify balance. The mean angle RMS of relative angular displacement of the hip, knee and ankle was calculated, and the mean angle RMS of absolute angular displacement of the trunk, thigh, shank, foot was calculated to quantify balance. Developing a greater understanding of complex dynamics of visual feedback on cognitive task that requires vision while quiet standing, may enhance our understanding of how visual information aids postural control during dual tasks.

Browse

Recent Submissions