Theses (Exercise Science)

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In September 2007, the name changed from School of Physical Education to School of Exercise Science, Physical and Health Education.

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Using vertical force-velocity profiling to predict swim start performance
(2025) Phillips, Kieran; Klimstra, Marc D.; Agar-Newman, Dana
The purpose of this study was to investigate the relationship between vertical force-velocity profiles (FVP) and swimming start performance. Twenty-four varsity-level swimmers (14 females and 10 males) with a mean age of 19.84 ± 1.50 years and body mass of 72.34 ± 7.39 kg were sampled from a varsity swimming program. Participants completed a FVP consisting of loaded squat jumps on force plates across four loads (female: 0.5 kg, 15 kg, 30 kg, 45 kg; male: 0.5 kg, 20 kg, 40 kg, 60 kg) and two maximal swimming starts during the same training week. Swim start performance was quantified using dive distance and time to 10 m. Multiple linear regression identified theoretical maximal force (F0) as a significant predictor of dive distance (β = 0.0212, R2 adjusted = 0.61, p <0.001) with no interaction effect being found for F0 and Sex. In contrast, none of the FVP variables significantly predicted time to 10 m, likely due to a high variability in underwater technique. This study highlights the importance of maximal strength for improving dive distance. However, for an athlete’s strength and power capacities to transfer to overall start performance, athletes must also dedicate time to practicing the start action itself.
Designing and implementing employee wellness frameworks: An action research approach
(2025) Wilkins, Erin; Meldrum, John T.; Buckler, Jean
This dissertation investigates employee wellness frameworks in post-secondary education institutes, contributing to the development of effective frameworks, to inform academic study in this area, and to support post-secondary institutions looking to use similar processes. The study is conducted through qualitative action research and has two research questions. The primary question is: What are the components of an employee wellness framework in the context of a post-secondary institution? The secondary question is: How can Langara College design and implement available framework for employee wellness that builds on their current initiatives? Through semi-structured interviews, data was collected from the Langara Employee Wellness Promotion Committee. In addition, data was collected through the review of internal college documents, intranet sites, and the college website. An external literature review was also conducted to inform the study’s recommendations. The findings of the study revealed that there is not one singular framework for implementing employee wellness in post-secondary institutions; frameworks must be designed to meet the unique needs of each institution and its stakeholders. This aligns with the current knowledge that was revealed while conducting the external literature review. The presented employee wellness framework is research-informed and transferable to any post-secondary institution. The Langara College recommendations for implementation can also inform the approaches of other institutions. Implications for future research are also discussed.
Invisible monitoring using athlete worn sensors in elite women's soccer
(2025) Cormier, Patrick; Klimstra, Marc D.
The primary objective of this dissertation was to develop valid and reliable monitoring of soccer players’ maximal acceleration and speed sprinting ability in an inobtrusive manner. To accomplish this goal, we studied methods that used observational data collected with sensors that are typically worn in every training and match in international level women’s soccer (i.e., invisible monitoring). First, to achieve this objective, it was necessary to evaluate the validity and reliability of different athlete athlete-worn sensors (global navigation satellite systems [GNSS]) against gold-standard devices for measurement of instantaneous velocity (radar) and standard time-distance sensors (timing gates). These sensors can be used to model and calculate various force-velocity (FV) metrics related to horizontal acceleration, velocity, force, power, and efficiency of the oriented force throughout linear sprinting protocols. It was demonstrated that GNSS sensors could be used to model linear sprints with adequate reliability and validity depending on the GNSS sensor used. Second, to provide a more comprehensive assessment of the state of GNSS for FV linear sprint profiling, a systematic review with quantitative (meta-analysis) and narrative analysis was carried out on the literature comparing GNSS to radar and laser. It was found through this process that GNSS can be valid and reliable, however, there are several methodological challenges that need to be considered which informed our research designs going forward and allowed for improvement of modeling recommendations for future research and application. Third, although having the ability to model linear FV sprint capacity in the field using GNSS sensors is impactful, it still requires a degree of protocol standardization and requires anthropometric and environmental metrics to be collected for effective modelling. Therefore, we evaluated a novel athlete monitoring approach that requires no dedicated sprint testing or additional metrics to be collected. Acceleration-speed (AS) profiles using regular training and game data were compared to FV profiles in an elite women’s soccer cohort to determine whether AS profiles could provide practitioners with similar information to FV profiling without the need for any isolated sprint testing. It was found that within a 4-week national team camp, it was possible to construct valid AS profiles that can inform practitioners on the acceleration and speed of the athletes in aggregated data sets of training and games. Since this data can contain outliers, multiple outlier techniques to construct AS profiles were also evaluated and shown to be an important aspect to consider. Fourth, since AS profiling was determined to be valid with 4-weeks of data which may not be ecologically valid due to variations in national team camp lengths (typically a week or longer), it was then necessary to determine the minimal number of events necessary to construct valid AS profiles. Therefore, an optimization approach whereby all possible combinations of 19 training or game events were performed, and it was determined that nine events were necessary for a valid profile to be constructed, and that the inclusion of maximal sprint efforts can improve the reliability and (reduce) the number of events necessary. In the fifth and final study, we conducted a larger scale analysis on 3-years of women’s national team training camp and international match data. Since the AS profiles represent the athletes AS ability during and surrounding the camp, we could use the AS regression as a reference to normalize the maximal speed and acceleration points across velocity bands typically used in soccer (i.e., low, moderate, high, and very-high speed running). This resulted in the introduction of novel invisible monitoring metrics such as normalized acceleration and power, which allowed for the quantification of athlete’s relative effort in matches compared to their physiological and biomechanical maximal capacity. These data were then used to demonstrate the differences and possible benefits of normalization or non-normalization of acceleration and power and how it varies based upon position, goal differential, and match half. Altogether, the findings from this thesis suggests that it is possible to reliably generate “invisibly” monitored acceleration-speed profiles in international women’s soccer contexts using GNSS technology. Further, AS profiling provides a benchmark for physical and tactical staff which can be compared to absolute athlete data and may inform rehabilitation, strength & conditioning programs, training sessions and match tactics. Further research is necessary to determine effective application in other team sports.
Evaluating the mental, social, and physical benefits of recreation programming for older adults
(2024) Payne, Celia; Buckler, Jean
Community centres play a vital role in promoting the health and well-being of older adults across Canada by offering programs that enhance recreational, nutritional, health, and social engagement. This study aimed to develop a comprehensive survey tool to evaluate the experiences, needs, and benefits of community centre involvement among adults aged 50 and older, with a specific focus on centres in Greater Victoria, British Columbia. A mixed-methods research design gathered responses from 336 participants across various municipalities, combining quantitative data with rich qualitative insights. Survey findings revealed significant impacts of community centre participation on physical, mental, and social well-being. Respondents reported improved physical health, including enhanced mobility, increased strength, and fitness gains from attending community centres. Mentally, participants reported reduced stress, increased motivation, and greater resilience. Socially, they reported forming meaningful connections, reducing feelings of isolation, and fostering a sense of belonging. Additional insights highlighted barriers, such as transportation challenges, caregiving responsibilities, and areas needing accessibility improvements. The survey was developed in collaboration with a working group and regional management, ensuring its alignment with public health priorities and practical relevance to community centre operations. This tool provides valuable data to guide and support future community programming, and the study culminates with implications for fostering healthy aging to continue to effectively support the growing older adult demographic. Ultimately, the results support the positive connection between community centre attendance and health benefits while strongly encouraging initiatives, like this study, that promote physical health, mental well-being, and social connectedness among older adults.
Co-designing a theory-driven severity/risk outcome report for Relative Energy Deficiency in Sport (REDs) with experts and athletes leads to higher knowledge, attitudes, and motivations
(2024) Zoras, Vanessa; Klimstra, Marc D.; Stellingwerff, Trent; Arcand, JoAnne
Background: Relative Energy Deficiency in Sport (REDs) negatively affects athlete health and performance. Although the International Olympic Committee (IOC) recommends a validated REDs clinical assessment tool (REDs CAT2) for use by physicians, no evidence-informed tool exists to facilitate its implementation. Objective: This study aims to co-design a severity/risk outcome report with end users and evaluate its effect on athlete REDs-related knowledge, attitudes, and motivations (KAM) compared to a control report. Methods: A prototype of a REDs CAT2 report was developed through discussions with REDs experts (n=10), an environmental scan, and the integration of theory (Phase 1). The report underwent iterative testing with athletes (n=15, Phase 2) and questionnaire-based usability and acceptability (U&A) assessments and verbal feedback were used to determine design modifications. A two-arm randomized controlled pilot study (Phase 3) was conducted to test the hypothesis that REDs-related KAM scores would be higher in athletes who used the refined REDs CAT2 report (n=47), compared those who used the control report (n=37). Results: Five report revisions based on four user testing sessions resulted in mean U&A scores exceeding 90%. Post-intervention assessments showed significantly higher U&A and REDs-related KAM scores in the experimental group (U&A = 66.7 ± 5.0; K = 10.5 ± 1.2; AM = 75.3 ± 5.1) compared to the control group (U&A = 60.3 ± 10.5; K = 9.5 ± 2.1; AM = 71.3 ± 6.6), after controlling for pre-intervention KAM scores. Conclusions: The report developed through this study offers a practical and cost-effective tool to facilitate the implementation of IOC policy recommendations and the REDs CAT2.
Bone health In adolescent female athletes: The influence of menstrual and oral contraceptive status on bone mineral density and content of the lumbar spine and proximal femur
(2002) DeNeef Ooms, Shana L.; Gaul, Catherine A.
The purpose of this research was to investigate the influence of menstrual status and oral contraceptive status on areal bone mineral density (aBMD) and bone mineral content (BMC) of the lumbar spine and proximal femur in 31 adolescent, athletic Caucasian, non-smoking females, aged 14 to 21 years (mean 18.8 ± 1.3 years). Participants were grouped by menstrual and oral contraceptive status: eumenorrheic, non-oral contraceptive users (ENOC, n=15), eumenorrheic, oral contraceptive users (EOC, n=11), and irregularly menstruating (amenorrheic and oligomenorrheic), non-oraJ contraceptive users (INOC, n=5). A secondary purpose was to determine if the ENOC, EOC and INOC groups were distinguishable by other factors which have been associated with aBMD and BMC, such as anthropometrics, age at menarche, physical activity, calorie and calcium intake, and eating attitudes. Subjects participated in a regular program of vigorous weight bearing activity that involved a minimum of 3 times per week for at least 45 minutes each time. Measures of aBMD and BMC of the lumbar spine (LS, L1-4), proximal femur (PF) and its sub regions, the femoral neck (FN) and trochanter (FT), were taken using a Hologic QDR 2000 dual energy x-ray absorptiometer (DXA) in array mode. Descriptive information regarding menstrual and oral contraceptive history, familial history of osteoporosis, medical history and current physical activity levels was gathered with a general health questionnaire. A three-day dietary record was used to assess calorie and calcium intake, and the Eating Attitudes Test (EAT-26) was used to evaluate restrictive eating tendencies. Anthropometrics including stature, weight, body mass index (BMJ), and sum of five skin folds (So5S) were also assessed. ENOC, EOC and INOC groups were similar in terms of chronological age, age at menarche, anthropometrics, current physical activity and resistance training (hours per week), and all dietary measures. Height and weight correlated significantly with measures of BMC and bone mineral area (BMA) (p<0.05), but not with measures of aBMD. Weight bearing activity and resistance training correlated significantly with aBMD of the FT and FN, respectively (p<0.05). Age at menarche, calorie and calcium intake, EAT-26 scores, and So5S did not correlate significantly with any of the bone mineral measures. A one-way ANOVA revealed that in non-oral contraceptive users (ENOC and INOC), menstrual status did not influence aBMD and BMC at the LS and PF. Conversely, in the eumenorrheic groups, oral contraceptive users (EOC) had significantly higher BMC at the PF (p=0.028) and FT (p=0.020) compared to non-oral contraceptive users (ENOC). Oral contraceptive use did not influence BMC at the LS or aBMD at any site. BMC at the PF may be influenced by initiation of oral contraceptive use prior to 20 years of age and before adult peak bone mass is achieved. Skeletal growth during puberty reflects increases in BMC more so than in aBMD because of increases in bone size. A longer period of bone mineral accrual after longitudinal growth has ceased, therefore, might be necessary before any influence of oral contraceptive use on aBMD is observed.
Cerebral endothelial function and pulsatile metaboreflex hemodynamics in adults
(2024) Taylor, Luc; Smith, Kurt
Few studies measuring cerebral blood flow (CBF) during metabolic afferent stimulation consider the mechanistic implications of endothelial function and compliance of vessels supplying the brain. The central question of this thesis study was whether pulsatile cerebral hemodynamic damping (DFi) plays a role in how the afferent muscle metaboreflex, a component of the exercise pressor reflex (EPR), impacts brain hemodynamics during exercise. Using ultrasound imaging techniques on 28 subjects (11 biological females, 17 biological males; 23.6±4.2 years of age; BMI of 24.0±3.2 kg/m^2), measures of DFi from the extracranial internal carotid artery (ICA) to the intracranial middle cerebral artery (MCA) were assessed during post-exercise muscle ischemia (PEMI) and transient hypercapnia (9% CO2). Endothelial function was indexed by the %Δ in ICA vessel diameter (ICAd) during transient hypercapnia using a Douglas bag technique. DFi did not change during a paced-breathing metaboreflex stimulation; stimulation of the blood pressure-dependent metaboreflex with a 30% maximal voluntary contraction (MVC) dynamic handgrip protocol that preceded post-exercise muscle ischemia (PEMI) was effective (p = 0.005). A 6.77±3.97% increase in ICAd was observed during transient hypercapnia (p = 0.021). Cerebral hemodynamic buffering is maintained in healthy young male and female adults. Transient hypercapnia via Douglas bag provides an easy stimulus to increase PetCO2 and shear stress to provoke ICA vasodilation. While no sex differences were observed in this study, future research could benefit from an increased sampling power to explore the impact of sex hormone levels. Additionally, considering healthy individuals appear to buffer cerebral hemodynamics, further mechanistic understanding is required to assess how aging and chronic disease-state populations lead to an impaired DFi.
Training care providers to facilitate physical activity of adults with intellectual disabilities: The inclusion of adult learning principles
(2024) Lamain, Nathaniel; Temple, Viviene A.
By increasing physical activity participation and reducing sedentary time, adults with intellectual disabilities can reduce the risk of preventable negative health outcomes. However, adults with intellectual disabilities often need support from others to optimize these health promoting behaviours. Care providers that work in community support organizations often lack knowledge and skills to support physical activity participation. In response, researchers and organizations that support individuals with intellectual disabilities have developed professional training to enhance care providers’ capabilities to enable physical activity participation. Centring the learner in the learning process and using principles of adult learning in the training design are important for intervention effectiveness. The aim of this thesis was twofold 1) to synthesize and evaluate the extant literature on physical activity-specific professional development training for care providers for the presence of adult learning principles, and 2) to pilot an intervention for care providers using existing Special Olympics resources supplemented by professional training that incorporates adult learning principles. The thesis is comprised of four manuscripts. The first two manuscripts (Chapters 2 and 3) are the systematic review protocol and the systematic review which address the first aim. Manuscripts 3 and 4 (Chapters 4 and 5) address the second aim. Manuscript 3 is the mixed-methods evaluation of the pilot study and manuscript 4 is a knowledge translation article conveying the intervention and lessons learned to practitioners.
Mechanisms of cerebral artery compliance at sea-level and following acclimatization to high altitude.
(2024) Underwood, Destiny; Smith, Kurt
Brain health is dependent on adequate cerebral blood flow (CBF) delivered through healthy compliant vessels that buffer pulsatile hemodynamic stress. Pharmacological interventions at sea-level (SL) and high altitude (HA, 5050m) that increase and lower CBF provide a useful experimental design to assess the mechanisms involved in buffering cerebrovascular hemodynamic stress. We characterized pulsatile hemodynamic damping factors (DFi), as an index of cerebral hemodynamic stress. DFi was calculated from pulsitility (PI) in the internal carotid (ICA) and middle cerebral arteries (MCA) at SL and HA following pharmacological attempts to increase (SL=Dobutamine, DOB; HA = DOB+Actetazolamide, DOB+ACZ) and decrease (Indomethacin; INDO) CBF in healthy lowlander adults (n=12, 4 females). Cerebrovascular hemodynamics in the ICA (flow [QICA], PIICA) and MCA (velocity [MCAv], PIMCA) were measured using ultrasound; DFi=PIICA:PIMCA. Administration of DOB (2-5μg/kg/min) at SL, DOB+ACZ (5μg/kg/min+10 mg/kg) at HA, and INDO (1.45 mg/kg) at SL and HA were performed on separate days in randomized order. No QICA response were observed following DOB, while QICA increased following DOB+ACZ (change+41±24 ml.min-1, p=0.01), and decreased following INDO at SL (change-53± 56 ml.min-1,p=0.04) and HA (change -41± 18 ml.min-1, p=0.004). DOB and DOB+ACZ administration differentially altered HR (change-3 bpm; change+5 bpm, p=0.02), ICAV (change-6 ± 10 cm.s-1; change+10 ± 11 cm.s-1; p=0.04), MCAv (change+0 ± 10 cm.s-1; change+17± 5 cm.s-1), and PIICA (change+0.4 ± 0.2 a.u; change +0.2 ± 0.09 a.u.; p=0.03). DOB reduced DFi (change -0.1± 0.05, p=0.02) at SL. Meanwhile DFi following INDO was significantly lower at HA (change -0.54± 0.3a.u, p=0.02) but not at SL (change -0.26± 0.3 a.u, p=0.18). The results from these two field experiments highlights that reducing CBF via cyclooxygenase inhibition detrimental alters the buffering of cerebrovascular hemodynamic forces. In contrast, at HA when CBF is increased following DOB+ACZ cerebrovascular hemodynamic regulation was preserved.
Innovations in In-Shoe Plantar Pressure Measurement Technology for Field Based Quantification of Running Gait
(2024-02-16) Blades, Samuel; Klimstra, Marc D.; Hundza, Sandra R.
Although substantial progress has been made in the field of running biomechanics, a significant portion of this research has been confined to laboratory settings. Data collection within the laboratory, while controlled, often lacks the ecological validity necessary to capture the complexities of athletes' performances in their natural training and competition environments. Given this need, in-shoe plantar pressure measurement technology is of primary importance due to its location of measurement and its unique capacity to deliver continuous measurements of both kinematic and kinetic biomechanical data. However, most commercially available in-shoe plantar pressure measurement systems (PPMS) are designed primarily for use in research settings and are thus unsuitable for field-based use due in part, to their high cost, low durability, and cumbersome hardware designs that can interfere with natural running gait. These limitations restrict researchers, athletes, coaches, and footwear designers from using PPMS to acquire valuable biomechanical data in training and competition environments. The development of a wearable, field-appropriate, in-shoe PPMS capable of providing lab-quality pressure data and its derivative biomechanical signals could address the current gap in measurement technology enabling significant advancements in running biomechanics research. The development of such a technology, however, is highly demanding due to many competing requirements such as low weight, high durability, imperceptible form factor, and cost-effectiveness while still providing lab-quality data. The purpose of this dissertation is to present research that could aid in the development of a wearable, field-appropriate, in-shoe PPMS through the following research objectives. The first research objective was to determine the accuracy and performance of a low-cost, fully integrated pressure sensing insole relative to a research-grade PPMS using laboratory-standard equipment on bench-top and in-situ performance tests (Chapter 2). The second research objective was to determine the optimal sparse sensor layout and plantar pressure distribution estimation method capable of measuring the complete plantar pressure distribution with lab quality accuracy (Chapter 3). The final research objective was to develop and determine the optimal foot contact event detection algorithms for use with plantar pressure data to enable highly accurate gait phase analysis (Chapter 4). The results presented in this dissertation demonstrate the feasibility of the development of a wearable, field-appropriate, PPMS that can provide accurate kinematic and kinetic data. The application of these findings can aid in the further development of wearable PPMS, leading to advancements in the field of running biomechanics and the sport of running.
Effect of Wearable Activity Trackers and Social Media Use on Day-Level Physical Activity Motivation and Behaviours
(2023-09-28) Coulter, Rebecca; Liu, Sam
Background. Physical activity (PA) is integral to maintaining good health yet physical inactivity remains a concern. Wearable activity trackers (WATs) have grown in popularity and research recognizes their potential impact on motivation and PA behaviours, specifically when combined with additional intervention strategies. Research has also shown positive associations between health-related social media use and PA. While both WATs and social media are potentially effective tools for behaviour change, research in this field has focused on between-person associations. Currently, less is known about within-person associations between WAT use and daily PA as well as potential interaction effects with daily health-related social media use. Objectives. 1) Examine differences in day-level situational motivation for PA between WAT users and non-users, 2) Examine within-person associations of day-level situational motivation for PA with same-day health-related social media use, 3) Examine differences in day-level PA intensity, duration, and moderate-to-vigorous physical activity (MVPA) in WAT users and non-users, and 4) Examine within-person associations of daily PA with same-day health-related social media use. Methods. English-speaking Canadian adults (≥ 18 years) were recruited. Eligible participants completed a baseline survey assessing social media use, WAT status and demographic information. Participants then completed up to three (3) daily surveys assessing daily situational motivation for PA, daily social media use and self-reported PA behaviours for 14 days. Multi-level modelling was conducted. Results. 328 participants were included. Mean age of participants was 27.2 (9.1) years, 67% (n=220) of participants were female and 71.3% (n=234) of participants identified as WAT users. WAT use was associated with greater intrinsic and identified situational motivation before engaging in daily PA. Daily health-related social media use was not found to be associated with greater autonomous situational motivation. The only significant interaction effect for WAT use and health-related social media was found for external regulation (b=0.23, SE 0.11, p = .03). WAT use was not associated with greater daily PA; however, daily social media use was significantly associated with PA intensity (b=0.29, SE 0.10, p < .01) and MVPA (b=3.38, SE 1.52, p = .026). No significant interaction effects were observed between health-related social media and WAT use for any PA outcome. Conclusions. Greater autonomous (intrinsic motivation, identified regulation) situational motivation for PA in WAT users did not translate to increases in PA behaviours. While daily social media use had no association with daily motivation for PA, results showed a significant association between health-related social media use and PA intensity as well as with MVPA. Alone, WATs and health-related social media use may influence situational motivation for PA and behaviours but no additional benefits on motivation or PA were observed when used in combination. Although WATs should be not discounted as an effective tool, health-related social media platforms could exert a more direct influence on actual PA engagement and is a potential positive addition to PA interventions. Future research should continue to examine the type and timing of health-related social media use to have an optimal effect on PA behaviours.
Fatigue in Wildland Firefighting: Relationships Between Sleep, Shift Characteristics, and Levels of Stress and Cognitive Function.
(2023-09-13) Wallace-Webb, Jesse; Stuart-Hill, Lynneth Ann; Coehoorn, Cory
Rationale: With climate change rising, the impact of wildfires is expected to increase. Wildland firefighting requires constant attention while exposed to harsh working conditions, including long working hours and sub-optimal sleep. These stressors may contribute to heightened stress and impaired cognitive function, which poses a risk to worker health and safety, respectively. Purpose: The current study’s objective was to investigate the associations between sleep, shift characteristics and levels of stress and cognitive function in Canadian wildland firefighters. Methods: Employing a within-subject observational study design, we recruited a geographically diverse sample of 25 wildland firefighters from the British Columbia Wildfire Service (BCWS). Remote data collection occurred between June and September of the 2021 and 2022 fire seasons, including in participants’ homes and at their work respective location. Wrist-worn actigraphy, heart rate variability (HRV), and the psychomotor vigilance task served as objective, mobile measures of sleep, stress, and cognitive function, respectively. Web-based methods were used to collect shift information, as well as subjective reports of stress and fatigue. Linear mixed effects modelling was used to statistically control for inter-individual differences. The influence of participant-factors such as age, biological sex, and years of firefighting experience was also explored. Results: Average sleep and shift durations on fire suppression days were 6.7 and 13.8 hours, respectively (SD: 66 mins; 108 mins). Polar sleep score was found to be the best sleep-related predictor of every outcome measure, except HRV. Poor sleep, according to sleep score, was significantly associated with increased levels of stress and fatigue across all metrics (p<0.01). Later evening bedtimes were non-significantly related to reduced HRV (p<0.1). Shift duration was found to be the best shift-related predictor of every outcome measure. Longer shift durations were significantly associated with increased levels of stress and fatigue across all metrics (p<0.001). No shift characteristic predicted HRV. Cross-level interactions were indicated for two relationships involving shift duration. Physical activity and meditation experience were found to moderate the relationship between shift duration and heart rate such that the strength of association tended to be stronger in individuals without meditation experience and individuals with low physical activity. Trait morning-eveningness, physical activity, and meditation experience all moderated the relationship between shift duration and subjective fatigue such that the association was stronger in morning type individuals, individuals with low physical activity, and individuals with meditation experience. Conclusion: Our findings show that wildland firefighters are often exposed to sub-optimal sleep and long shifts. Importantly, poor sleep and long shift durations were associated with heightened levels of stress and impaired cognitive function, which have implications for worker heath and safety. We contribute novel findings to the field of research on occupational health and safety. We also provide insight and recommendations towards improved fatigue management policy within the BCWS by supporting the development, implementation, and continuous improvement of a practical and scientifically defensible fatigue risk management system.
Examination of the Relationships Among Physiological Stress, Iliopsoas Tightness and Non-Specific Chronic Low Back Pain in an Adult Population
(2023-08-31) Nash, Arielle; Stuart-Hill, Lynneth
One of the most prevalent forms of pain to be linked to stress is non-specific chronic low back pain (nsCLBP). Existing studies have shown evidence of a link between stress and nsCLBP, muscle tension induced dysfunctional biomechanics and nsCLBP, and stress and muscle tension. However, little research has explored the interconnections among muscle tension, stress and nsCLBP. The purpose of this study was to investigate the relationships between these variables. Two age and sex matched subgroups (nsCLBP, and noPain) with 17 participants each (M = 8, F= 9) were created from an overall participant group (n =39, M = 18, F = 21, 23- 63 y). Iliopsoas tightness was assessed by measuring hip extension angle (HE) with a goniometer on the left (HE L) and right (HE R) side using the modified Thomas test. Heart rate variability was recorded in laying supine position for 12-minutes. A 5-minute segment extracted for analysis of low frequency power (LF; ms2), high frequency power (HF; ms2), LF/HF ratio and the inter-beat intervals of normal N-N sinus beats (SDNN; ms). Cortisol concentration (CORT; nmol/L) was measured using a passive drool sample taken within 2 hours of waking. Each participant was measured for all variables in one session. Significant positive correlations were found between HE and HF (r(37) = .36 - .43, p < .05) and HE and SDNN (r(37) = .27 - .41, p ≤ .05). LF/HF and CORT were negatively correlated to HE L (r(36) = -.36, p = .01). The nsCLBP group measured significantly lower ranges of motion than the noPain group for both the left and right side hip extension, with the largest difference in means of HE between groups found on the right side (8.96o ± 3.10, t (32)= 2.88, p =.003). There were no significant differences in CORT or HRV between the groups. The results demonstrate that iliopsoas tightness can negatively impact physiological stress and vice versa. The findings also provide evidence that individuals with nsCLBP have, on average, less range of motion in hip extension when compared to pain free individuals. In addition, the correlation between muscle tension and stress is stronger among individuals with nsCLBP than among pain-free individuals.
Analysis of sleep and sleep hygiene in relation to the 2020 24-Hr Canadian Movement Guidelines among adults with intellectual and developmental disabilities: A Pilot Study
(2023-05-17) Coxon, Matthew; Stuart-Hill, Lynneth Ann; Temple, Viviene A.
Background: A variety of physiological and behavioural factors contribute to adults with Intellectual and Developmental Disabilities (IDD) being at high risk of problems with sleep duration and sleep quality. Sleep problems in this demographic may have been exacerbated by changes and restrictions in place due to the COVID-19 pandemic. Objective: The objective of this pilot study was to determine if collecting field data using smartwatch technology and sleep and physical activity diaries was feasible in this population. Utilizing these methodologies, the main goal was to monitor the sleep duration and sleep quality of adults with IDD and to compare those findings to the recommendations in the Canadian 24-Hour Movement Guidelines. Additionally, sleep hygiene behaviours and daily activities were recorded to further understand relationships between sleep and these variables. Methods: Participants (n = 15) were invited to wear a Polar Ignite smartwatch for a 9-day period and instructed how to complete a sleep and physical activity diary. Total sleep, actual sleep, sleep disturbances, and physical activity were recorded quantitatively using actigraphy. Behaviours were assessed using the sleep and physical activity diary. Results: Participants were able to consistently wear the smartwatch and report information in the sleep and physical activity diary. The majority of participants did not meet sleep duration guidelines based on their weekly average, with 9 out of 15 participants outside the guideline recommendations and only 1 participant meeting the guidelines every night. Participants regularly reported problems with their sleep and smartwatches recorded an average of 35:40 minutes (SD = 10:50) of sleep disturbances each night. Screen time before bed was the most common adverse sleep hygiene behaviour. Screen time was negatively, but not significantly correlated with total sleep (r = -0.34, p > 0.1) and actual sleep (r = -0.33, p > 0.1). Average moderate-vigorous physical activity (MVPA) was significantly correlated with sleep disturbances. This relationship was negative and moderately strong (r = -0.57, p < 0.05). Conclusions: This pilot study highlights that participants were able to provide seven days of sleep data and adhere to reporting their daily behaviours via a sleep and physical activity diary. Additionally, sleep duration and quality were not adequate in most participants. It is also likely that before-bed screentime had an adverse effect on sleep duration. Physical activity, on the other hand, had a positive effect on reducing sleep disturbances. These results suggest fruitful lines of enquiry, and future research with larger samples of adults with IDD are recommended to understand these relationships further. Researchers should have an ultimate objective of optimizing sleep, which in turn, would improve the health status of adults with IDD.
Were adults with intellectual disability (ID) meeting the 2020 Canadian 24-hour movement guidelines during COVID-19? A pilot study
(2023-04-28) Coats, John Cooper; Stuart-Hill, Lynneth Ann; Temple, Viviene A.
Maintaining a healthy lifestyle is crucial to reducing the risk of chronic disease and improving overall health and well-being. However, individuals with intellectual disability (ID) experience high levels of physical inactivity, sedentary behaviour, and poor sleep, leading to detrimental health outcomes. This pilot study investigated the extent to which adults with ID met the 2020 Canadian 24-hour Movement Guidelines during COVID-19. This pilot study followed a 9-day observational cross-sectional design and included 15 adults (6F, 9M) between the ages of 20-64 years. Using commercially available wearable technology, moderate-to-vigorous physical activity (MVPA) and sedentary time were extrapolated using heart rate, and total sleep time was measured to compare to guidelines. A novel diary subjectively tracked the number of bouts and types of physical activity performed. Of the 15 participants, 11 met the MVPA guideline (73%), 4 met the sedentary behaviour guideline (27%), 7 met the sleep guideline (47%), and only 1 participant met all 3 of the guidelines (7%). There were no significant differences for MVPA, light-physical activity (LPA), and sleep between weekdays and weekend days, or between females and males. Walking, cleaning dishes, and swimming were the most common types of physical activity performed by participants. Spearman’s rank-order correlations showed very low positive correlations between the number of physical activity bouts reported and the number of movement guidelines met, weekly MVPA, weekly sedentary time, sleep, and body mass index. Findings from this pilot study indicate a real need to improve sleep and reduce sedentary time by adults with ID. This pilot study recommends building on the objective and subjective measures used in this study in further research on physical activity and sleep in adults with ID.
A Feasibility Study Evaluating an Online Physical Activity Intervention for Young Adults with Low Mood and/or Depression Engaged in Community Primary Clinical Care
(2023-03-17) Ross, Aleah; Rhodes, Ryan E.
Background: Exercise is now recommended as a frontline treatment for depression (DS) in Canada. Implementation is an ongoing challenge. Purpose: The aim of this study was to evaluate the feasibility of a novel, online, physical activity (PA) intervention for youth with DS. Methods: Study 1: Semi-structured interviews were conducted with end-users to evaluate an existing alpha-intervention and inform intervention changes. Study 2: This study was a randomized, feasibility pilot trial of a 10-week, online, PA beta-intervention designed using the Multi-Process Action Control (M-PAC) framework with a waitlist control. Youth aged 19-30 with mild to moderate DS not meeting Canada PA guidelines were recruited via community clinics and social media. Primary feasibility outcomes were recruitment rate, retention rate, and acceptability. Planned analyses included a qualitative thematic analysis, frequency counts and multiple one-way, between-groups ANCOVAs. Results: Study 1: Thematic analysis of seven participants’ interview data determined good initial acceptability, demand, and practicality. Five change ideas were integrated within a beta-intervention for trial. Study 2: Low rates of recruitment (N= 26, 21.7% total; 3.8% clinical), retention (n= 16, 61.5%), and acceptability (n= 11, 64.0%) were found. Secondary outcomes of PA (partial eta squared = 0.55) and DS (partial eta squared = 0.18), as well as tertiary M PAC behaviour variables: behaviour regulation (partial eta squared = 0.46) and identity (partial eta squared = 0.20), all favored the intervention group. Conclusions: Despite initial evidence of acceptability and demand, this trial is not recommended for RCT; rather further pilot research is required including active control group(s) and multi-site approaches to bolster recruitment
A Remote Acceptance-Based Affect Regulation Intervention to Promote Physical Activity Among Early Career Professionals: A Mixed Methods Examination of Feasibility
(2023-01-17) Grant, Stina J.; Rhodes, Ryan E.
Background: The benefits of physical activity (PA) are well-established, yet much of the population is insufficiently active to reap optimal health effects. Early career professionals (ECPs) comprise one transitional group at-risk for inactivity and therefore a critical target for PA promotion. A web-based intervention utilizing online modules and podcasts represents an innovative delivery format for this time-pressed population; however, theoretical mechanisms of action and corresponding behaviour change techniques need to be honed to effectively increase PA. Affective state (e.g., challenging emotion or mood) is one factor that contributes to an established intention-behaviour gap and is especially pertinent among ECPs who face many demands and stressors. As such, an intervention designed to foster intention translation, strengthen emotion regulation, and mitigate the effect of incidental affect (e.g., work-related stress on PA engagement) to assist with PA initiation is warranted. This study uses a parallel randomized controlled design to explore the feasibility of a web-based intervention grounded in the Multi-Process Action Control (M-PAC) Framework and with a specific focus on Acceptance and Commitment Therapy (ACT) principles to promote PA among ECPs. Objectives: 1) To examine primary outcomes related to the feasibility and acceptability of a six-week web-based intervention and 2) explore the effects of the intervention on secondary outcomes of interest including moderate-to-vigorous PA (MVPA), emotion regulation, M-PAC constructs, and ACT constructs (acceptance, valued living, and mindfulness). Methods: Adults aged 25-44 residing in Canada who were employed at least part-time in a desk-based job and identifying as not meeting PA guidelines (<150 min MVPA) were recruited. Participants were randomized into a 6-week online intervention or a wait-list control group using a mixed block design. The intervention group gained access to 6-weekly self-guided online modules incorporating select M-PAC iii iv constructs and integrating ACT principles with an emphasis on affect regulation strategies. Short podcast episodes were offered as a complement to the lesson concepts. Primary feasibility outcomes were descriptive and included recruitment, retention, engagement and adherence. Satisfaction and acceptability were measured via self-report and through qualitative interviews. Secondary outcomes of MVPA, emotion regulation, M-PAC constructs, and ACT constructs were assessed via self-report at baseline and post-intervention at 6 weeks using questionnaires. Effect sizes were calculated using analysis of covariance to control for baseline values. Results: Twenty-six adults were recruited and randomized to the web-based intervention (n=14) and waitlist control (n=12) groups. The recruitment rate was 35%, retention was 73%, engagement was 63%, and satisfaction was high (M = 2.68/4; M = 4.07/5). Qualitative feedback was highly positive and suggestions for intervention improvement were themed around ideas for strengthening engagement, increasing podcast awareness, and addressing minor technical issues. Participants logged in 4.57 times (SD = 3.30) and spent 31.6 minutes (SD = 18.25) per week on the intervention. Participants allocated to the intervention improved MVPA (ηp2 = 0.53), emotion regulation (ηp2 = 0.42), M-PAC action control constructs of behavioural regulation (ηp2 = 0.48), affective attitude (ηp2 = 0.26), identity (ηp2 = 0.11), and ACT-related constructs of mindfulness (ηp2 = 0.47), valued living (ηp2 = 0.20), and acceptance and action (ηp2 = 0.07), Conclusion: The recruitment, retention, and engagement rates were adequate while satisfaction was favourable, suggesting a full-scale randomized controlled trial is feasible with minor modifications. Secondary outcomes showed movement in the hypothesized direction suggesting intervention fidelity. A large-scale study is warranted to establish intervention effectiveness.
Predicting Barbell Takeoff Speed from Peak Speed in the Bench Press Throw using a Linear Position Transducer
(2023-01-05) Henneberry, Molly; Klimstra, Marc D.
In order to determine if the takeoff speed of a barbell in a bench press throw may be predicted from the peak speed as measured by a linear position transducer, 10 participants with at least 1 year of resistance training experience performed multiple sets of the bench press throw, at increasing loads, on a vertical Smith machine. Predictive validity was assessed by comparing the estimated takeoff speed, to the measured takeoff speed from a linear position transducer. The relationship between peak and takeoff speed was 0.2589e0.897(PS), and the correlation was statistically significant (R2=0.961, p < 0.05). A Bland-Altman plot revealed the 95% limit of agreement ranged from 0.262 m∙s-1 to 0.175 m∙s-1, with a mean difference of 0.043 m∙s-1 (2.92%), and points above and below zero, suggesting no systematic bias exists. This study demonstrates that takeoff speed of a barbell may be predicted from its peak speed in a barbell bench press throw using a linear position transducer. Therefore, practitioners may use peak speed to estimate takeoff speed more quickly in field testing, when the accessibility and availability of equipment necessary to measure takeoff speed may be a limiting factor.
Teaching and learning nature-based physical activity in Physical and Health Education: From pre-service teachers to K-12 students
(2022-08-30) Gruno, Jennifer; Gibbons, Sandra Louise
The overall aim of this dissertation was to better understand the learning and teaching of NBPA in PHE experiences for teachers and adolescent students. A secondary aim was to better understand the learning and teaching cycle for NBPA reform in PHE. To achieve these aims, I conducted three interrelated studies that explored: (a) how pre-service teachers learn to teach NBPA in PHE, (b) in-service educators’ perspectives on learning and teaching NBPA, and (c) adolescent student experiences with NBPAs in and beyond PHE. These three studies explored the learning cycle from pre-service instruction, to in-service professional development, to, finally, the impact on the students’ learning. Individual findings are discussed in each of the three studies, and two overarching themes are discussed as findings for the overall body of research: (a) NBPA as a conduit for place- and land-based education; and (b) NBPA as an effective form of PHE reform.
Beyond the brain: exploring causes and effects of head trauma in combat sports
(2022-07-04) Follmer, Bruno; Zehr, E. Paul
Traumatic brain injury, concussion, and subconcussion are different clinical conditions associated with head injury. These conditions share a common origin, mechanical forces directly or indirectly transmitted to the head. In sports, modalities with high exposure to head traumas require further investigation, especially those in which strikes directly to the head are allowed and a determinant of success, such as combat sports. The causes and effects of brain injuries in combat sports such as Mixed Martial Arts, boxing, Muay Thai, and kickboxing are complex and require a comprehensive investigation of many factors. The objective of this dissertation was to explore the main causes that justify combat sports as the main sport sample when it comes to head injury and the effects of chronic exposure to head trauma in this population. Original studies were developed to assess the head injury risk in competition and in training, the level of knowledge of athletes and coaches, and the consequences of chronic exposure to head traumas in the balance function, brain activity, and spinal cord excitability. The risk of a fight ending due to head strikes in competition is directly related to the weight category, and the risk seems to be exacerbated in female athletes. Combat sports athletes are exposed to numerous strikes to the head in simulated fights on a weekly basis in training, when healthcare professionals are absent. During this time that makes up the bulk of exposures, therefore, athletes and coaches are the ones managing potential cases of concussion. However, coaches are not familiar with assessment tools and don’t often seek out concussion knowledge. Alarmingly, coaches, often prior athletes themselves, are the main source of concussion knowledge for their athletes. High exposure to head trauma both in competition and training in addition to iv poor knowledge and behavior are liable to cause consequences in the nervous system. Athletes chronically exposed to head trauma presented subtle deficits in static balance in the most basic human stance, which is the double-leg over a firm surface. Moreover, while the literature consistently shows impairments in brain function, our study expanded the association between head trauma and nervous system deficits to the least studied component of the nervous system, the spinal cord. While athletic training promotes neuroplastic benefits in spinal cord excitability, these were hindered in a sample of athletes chronically exposed to head traumas. The studies in this dissertation demonstrated that athletes in combat sports are chronically exposed to intentional and repetitive head traumas, and that this exposure is likely associated with long-term functional detriments in balance and spinal cord excitability.

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