Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 10 of 10

Full-Text Articles in Life Sciences

Exercise As A Treatment For Cognitive Decline In Older Adults: The Role Of Growth Factors And Inflammatory Cytokines, Joshua A. Titus Dec 2021

Exercise As A Treatment For Cognitive Decline In Older Adults: The Role Of Growth Factors And Inflammatory Cytokines, Joshua A. Titus

Electronic Thesis and Dissertation Repository

The purpose of this thesis was to investigate the effects that exercise modalities have on neurotrophic and inflammatory blood markers and cognitive outcomes in older adults. A systematic review and meta-analysis were completed. The included studies illustrated that most of the literature evaluated the effect of aerobic exercise interventions on systemic concentrations of the blood marker brain-derived neurotrophic factor (BDNF). The review found that aerobic exercise increases BDNF and resistance training increases insulin-like growth factor 1 (IGF-1). Interventions with sex-specific cohorts presented advantages in males for blood marker and cognitive outcomes compared to females. One of three included interventions decreased …


Direct Electrical Stimulation Of Prefrontal Cortex Modulates The Transient Heart Rate Response To Exercise In Conscious Humans, Bartek Kulas Nov 2021

Direct Electrical Stimulation Of Prefrontal Cortex Modulates The Transient Heart Rate Response To Exercise In Conscious Humans, Bartek Kulas

Electronic Thesis and Dissertation Repository

Prefrontal cortical regions play an essential role in generating appropriate cardiovascular adjustments, particularly in cardio-vagally mediated heart rate (HR) responses to active tasks. Functional imaging studies provide correlational evidence that this region coordinates HR responses to exercise, however, direct experimental evidence of prefrontal cortical HR regulation in humans is not available. Seven persons with epilepsy implanted with intracranial electroencephalography (iEEG) completed 2-second isometric handgrip (IHG) contractions at no-stimulation (NO-STIM) or sham-stimulation (SHAM) conditions, and during direct electrical stimulation (STIM) of the orbitofrontal and medial prefrontal cortex. HR responses to IHG during NO-STIM and SHAM increased HR by Δ4.9±2.7 bpm, compared …


Examining The Effects Of A Weight Stigma Induction On Psychological Stress And Exercise Outcomes, Isabella J. Randall Aug 2021

Examining The Effects Of A Weight Stigma Induction On Psychological Stress And Exercise Outcomes, Isabella J. Randall

Electronic Thesis and Dissertation Repository

Weight stigma is highly prevalent as a motivational tool in exercise contexts. However, weight stigma experienced in this domain may contribute to lowered exercise engagement, particularly among higher-weight women. This thesis examined the effects of a weight stigma induction on psychological stress, intentions to exercise (ITE), and exercise behaviours. Higher-weight women (N = 170, Mage = 57.2) were randomly assigned to read a fictional news article (weight-stigmatizing vs neutral condition), and completed acute measures of psychological stress, ITE, and exercise behaviours 7-days later. Participants who were exposed to the stigmatizing content reported a significant increase in stress and …


A Mechanistic View Of Mental Fatigue And Motor Performance: Implications Of Sex, Physical Activity And Sleep Quality, Katie L. Kowalski Aug 2021

A Mechanistic View Of Mental Fatigue And Motor Performance: Implications Of Sex, Physical Activity And Sleep Quality, Katie L. Kowalski

Electronic Thesis and Dissertation Repository

Sustained attention on a task leads to the development of mental fatigue, which is characterized by increases in perceived fatigue and associated with declines in submaximal exercise performance. However, the neuromuscular mechanisms underlying the relationship between mental fatigue and declines in motor performance are unclear and it is unknown if there are sex-specific responses to mental fatigue. Accordingly, the overall objective of this dissertation was to examine sex-specific differences in the impact of mental fatigue on neuromuscular function and motor performance in young adults. This objective was achieved through three studies by investigating neuromuscular function of the tibialis anterior (electrophysiological …


Examining The Feasibility Of Delivering A Multi-Component Virtual Lifestyle Medicine Program For Adults With Type 2 Diabetes, Madison S. Hiemstra Jul 2021

Examining The Feasibility Of Delivering A Multi-Component Virtual Lifestyle Medicine Program For Adults With Type 2 Diabetes, Madison S. Hiemstra

Electronic Thesis and Dissertation Repository

BACKGROUND: The virtual delivery of lifestyle medicine programs (e.g., via web-conferencing platforms) can increase program accessibility for adults living with type 2 diabetes (T2D). PURPOSE: To assess the feasibility of virtually delivering a multi-component group-based lifestyle medicine program that uses wearable technologies and exercise prescriptions in an adult population with T2D. METHODS: This was a six-week, single-cohort feasibility study. The virtual lifestyle medicine program included live-video delivery of group education classes, one-on-one exercise counselling phone calls, flash glucose monitors, wearable activity monitors, and exercise prescriptions. Several feasibility outcomes were assessed including recruitment and retention rates, acceptability (e.g., exit survey), and …


Spinal Excitability Changes Following Sensory Electrical Stimulation Of The Forearm, Devin K. Box Jun 2021

Spinal Excitability Changes Following Sensory Electrical Stimulation Of The Forearm, Devin K. Box

Electronic Thesis and Dissertation Repository

Sensory electrical stimulation can be used to suppress tremor in Parkinson’s disease. This study investigated the central mechanism underlying this suppression in healthy participants. Reciprocal inhibition (RI) of the wrist flexors before and after a session of sensory electrical stimulation (SES) applied to the antagonistic extensor muscles was assessed using electromyography. It was hypothesized that a 15-minute session of SES, rated by participants as a 3 on a 0-10 pain scale, would produce an increase in RI. Seven of the 18 participants experienced an increase in RI at 0-5 minutes post stimulation, which returned to baseline at 10-15 minutes. The …


“One Of The Most Elaborate Doping Ploys In Sports History”: The Impact Of The 2016 Russian Doping Scandal On Anti-Doping, Wada And Athletes’ Rights, Mikael J. Gonsalves Apr 2021

“One Of The Most Elaborate Doping Ploys In Sports History”: The Impact Of The 2016 Russian Doping Scandal On Anti-Doping, Wada And Athletes’ Rights, Mikael J. Gonsalves

Electronic Thesis and Dissertation Repository

This dissertation analyzes the impacts of the 2016 Russian doping scandal from a philosophical and historical perspective. This dissertation’s second chapter, the article entitled (1) “The Brave New World of Athletes’ Rights: A Canadian Perspective on Significant Shifts for the World Anti- Doping Agency” in time for the World Anti-Doping Agency’s (WADA) 20 th anniversary, puts into words the new investigative reality of contemporary anti-doping. It explains a new attitude of anti-doping authorities in response to the ‘game-changing’ Russian manipulation of samples, what has been described as “one of the most elaborate doping ploys in sports history” 1 (Icarus, 2016) …


Post-Activation Potentiation Induced By Concentric Contractions At Three Speeds In Humans, Alexander Zero Apr 2021

Post-Activation Potentiation Induced By Concentric Contractions At Three Speeds In Humans, Alexander Zero

Electronic Thesis and Dissertation Repository

Post-activation potentiation (PAP) is the acute enhancement of contractile properties following a short duration (<10s) high intensity contraction. Compared with isometric contractions, little is known about the PAP response induced by concentric conditioning contractions (CCs) and the effect of contractile speeds. In the dorsiflexors of 10 participants, twitch responses were measured following 5s of maximal effort concentric CCs at each of 10, 20 and 50°/s. Concentric PAP responses were compared to a maximal isometric voluntary contraction (MVC) matched for contraction time. Additionally, concentric CCs were compared to isometric CCs matched for mean torque, contraction area and time. The principal finding was that the PAP response following maximal concentric CCs was independent of contractile speed and, there was no difference in the PAP response between concentric CCs and an isometric MVC. Maximal contractions, regardless of contraction modality, likely produce sufficient Ca2+ to induce a full PAP response, and thus there was no difference between speeds or contraction type. Concentric CCs had significantly larger peak twitch torque than their isometric torque matches (49-58%), and faster maximal rates of torque development at the three speeds (62-77%). However, these responses are likely related to greater muscle activation (EMG), and not contraction modality per se. Thus, PAP responses following maximal concentric CCs are not affected by velocity and responses are not different from an isometric MVC. This indicates maximal …


Sexual Dimorphism In Response To Repetitive Bouts Of Acute Exercise In Rodents With Type 1 Diabetes Mellitus, Jordan C. Larocque Feb 2021

Sexual Dimorphism In Response To Repetitive Bouts Of Acute Exercise In Rodents With Type 1 Diabetes Mellitus, Jordan C. Larocque

Electronic Thesis and Dissertation Repository

The purpose of this study was to examine sex-specific differences in the blood glucose (BG) response to recurrent aerobic exercise in type 1 diabetes. Specifically, we examined the role of peak estrogen (E2) concentrations during proestrus on BG response to prolonged aerobic exercise. To do so, nineteen Sprague-Dawley rats were assigned to four exercised groups: control female (CXF; n = 5), control male (CXM; n = 5), diabetic female (DXF, n = 5) and diabetic male (DXM, n = 4). Diabetes was induced in DX groups via subcutaneous injection of low dose streptozotocin. After four days of exercise, liver glycogen …


Recognizing Parasport Impacts: Ripples, Waves, And Echoes, Adam J. Purdy Feb 2021

Recognizing Parasport Impacts: Ripples, Waves, And Echoes, Adam J. Purdy

Electronic Thesis and Dissertation Repository

Major Games such as the 2015 Parapan American Games in Toronto (TO2015) generate the potential to bring awareness to sport participation opportunities for people with impairment (Chalip et al, 2017). In the post-games era, it is important to examine the ways in which sport program managers recognize the outcomes of games-related leveraging initiatives. Teleconference interviews were conducted with twelve program managers in the Greater Toronto Area. The study followed an interpretive descriptive methodology and employed a theoretical construct of recognition as a novel approach to assess the legacy and social impacts of hosting parasport games. A form of thematic analysis …