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Theses/Dissertations

Kinesiology

Western University

Heart rate variability

Publication Year

Articles 1 - 3 of 3

Full-Text Articles in Life Sciences

Cardiodynamic Associations With Resilience In Undergraduate Students And The Effect Of A Mentorship Intervention, Rachel J. Knetsch Oct 2018

Cardiodynamic Associations With Resilience In Undergraduate Students And The Effect Of A Mentorship Intervention, Rachel J. Knetsch

Electronic Thesis and Dissertation Repository

The National College Health Assessment (NCHA) indicates that a majority of Canadian university students report feeling overwhelmed, stressed, and anxious during their undergraduate studies. Resilience refers to positive adaptation, or the ability to maintain or regain mental health, despite experiencing adversity (Herrman et al., 2011). While autonomic indices have been used to describe chronic physiological stress, the role of heart rate variability (HRV) as an index of resilience remains unclear. This research tested the hypotheses that (1) there is a relationship between HRV and resilience scoresand (2) a mentorship intervention will improve HRV and resilience outcomes. Fifty-seven first year students ...


Somatosensory Stimulation Modulates Heart Rate Variability Changes Induced By Isometric Handgrip Exercise, Jacquie Baker Jul 2013

Somatosensory Stimulation Modulates Heart Rate Variability Changes Induced By Isometric Handgrip Exercise, Jacquie Baker

Electronic Thesis and Dissertation Repository

Functional imaging reveals overlapping forebrain and basal ganglia regions associated with heart rate (HR) and heart rate variability (HRV) regulation. Somatosensory stimulation (STIM) and isometric handgrip (HG) were used to test the hypotheses that a) STIM would modulate HG-induced changes to HR and HRV, and b) HG+STIM would produce different cortical activation relative to HG alone (n=12). During STIM, high-frequency (HF)-HRV increased (p<0.05), whereas HR did not change. During HG, HF-HRV decreased (p<0.01) while HR increased (p<0.001). HG+STIM reversed the HG-induced change in HF-HRV (p<0.01). However, the HR response to HG remained unaffected. HG increased insular activation, while ventral medial prefrontal cortex (vMPFC) activity decreased. HG+STIM produced similar vMPFC deactivation. However, insular activation was no longer evident. These data indicate that somatosensory inputs through STIM can modulate HG-induced changes to HF-HRV. Different insular activations during HG versus HG+STIM suggest afferent signals to the insula may inhibit descending motor signals affecting HF-HRV.


Associations Between Heart Rate Variability And Metabolic Syndrome Risk Factors, Melanie I. Stuckey May 2013

Associations Between Heart Rate Variability And Metabolic Syndrome Risk Factors, Melanie I. Stuckey

Electronic Thesis and Dissertation Repository

Metabolic syndrome (MetS) is a clustering of risk factors for cardiovascular disease (CVD) and type 2 diabetes (T2D) – two major causes of morbidity and mortality worldwide. Heart rate variability (HRV) is a non-invasive measure of cardiac autonomic regulation that predicts mortality and morbidity. Additionally, HRV is reduced in CVD, T2D and MetS. As such, HRV has potential to be a novel cardiometabolic risk factor to be included in clinical risk assessment. Therefore, the purpose of this thesis was to examine the relationships between MetS and HRV. A systematic review of cross-sectional studies examining relationships between HRV and MetS was completed ...