A5000007003- Cardiovascular and exercise physiology
- Heart Rate Variability and Autonomic Control
- Cardiovascular Health and Disease Prevention
- Cardiovascular Disease and Adiposity
- Adipose Tissue and Metabolism
- Cardiovascular Function and Risk Factors
- Nitric Oxide and Endothelin Effects
- Sports Performance and Training
- Cerebrovascular and Carotid Artery Diseases
- Adipokines, Inflammation, and Metabolic Diseases
- Diet and metabolism studies
- Pain Mechanisms and Treatments
- Cardiovascular Effects of Exercise
- Birth, Development, and Health
- Traumatic Brain Injury and Neurovascular Disturbances
- Blood Pressure and Hypertension Studies
- Neuroscience of respiration and sleep
- Physical Activity and Health
- Cardiac electrophysiology and arrhythmias
- Cardiac Fibrosis and Remodeling
- Cardiovascular Conditions and Treatments
- Pancreatic function and diabetes
- Neurological Disease Mechanisms and Treatments
- Cardiovascular, Neuropeptides, and Oxidative Stress Research
- Metabolism, Diabetes, and Cancer
University of Saskatchewan
2018-2025
University of Missouri
2015-2023
Western University
2010-2017
University of Leeds
2015
Canadian Society for Exercise Physiology
2014
Repeated maximal-intensity short-duration exercise (sprint interval training, SIT) can produce muscle adaptations similar to endurance training (ET) despite a much reduced volume. However, most SIT data use cycling, and little is known about its effects on body composition or maximal cardiac output (Qmax).The purpose of this study was assess composition, 2000-m run time trial, VO(2max), Q(max) versus ET.Men women (n = 10 per group; mean ± SD: age 24 3 yr) trained three times week for 6 wk...
Six weeks (3 times/wk) of sprint-interval training (SIT) or continuous endurance (CET) promote body-fat losses despite a substantially lower volume with SIT. In an attempt to explain these findings, the authors quantified VO₂ during and after (24 h) exercise (SIE; 2 min exercise) vs. (CEE; 30 exercise). was measured in male students (n = 8) 8 times over 24 hr under 3 treatments (SIE, CEE, control [CTRL, no exercise]). Diet controlled. 150% greater (p < .01) CEE SIE (87.6 ± 13.1 35.1 4.4 L...
Data on whether sprint interval training (SIT) (repeated supermaximal intensity, short-duration exercise) affects body composition are limited, and the data that available suggest men respond more favourably than do women. Moreover, most SIT involve cycling exercise, running may differ because of larger muscle mass involved. Further, is a universal exercise type. This study assessed can alter (air displacement plethysmography), waist circumference, maximal oxygen consumption, peak speed,...
The development of new treatments for heart failure lack animal models that encompass the increasingly heterogeneous disease profile this patient population. This report provides evidence supporting hypothesis Western Diet-fed, aortic-banded Ossabaw swine display an integrated physiological, morphological, and genetic phenotype evocative cardio-metabolic failure. preclinical model displays a distinctive constellation findings are conceivably useful to extending understanding how pre-existing...
In response to acute physiological stress, the sympathetic nervous system modifies neural outflow through increased firing frequency of lower-threshold axons, recruitment latent subpopulations higher-threshold and/or modifications synaptic delays. Aging and coronary artery disease (CAD) often modify efferent muscle nerve activity (MSNA). Therefore, we investigated whether CAD (n = 14; 61 ± 10 yr) healthy aging without (OH; n 59 9 modified these strategies that normally are observed in young...
Impaired microvascular insulin signaling may develop before overt indices of endothelial dysfunction and represent an early pathological feature adolescent obesity. Using a translational porcine model juvenile obesity, we tested the hypotheses that in stages obesity development, impaired manifests skeletal muscle (triceps), brain (prefrontal cortex), corresponding vasculatures, depressed insulin-induced vasodilation is reversible with acute inhibition protein kinase Cβ (PKCβ). Juvenile...
Sympathetic outflow is modified during acute homeostatic stress through increased firing of low-threshold axons, recruitment latent and synaptic delay modifications. However, the role central mechanisms versus peripheral reflex control over sympathetic remains unknown. Here, we examined discharge patterns fatiguing static handgrip (SHG) exercise postexercise circulatory occlusion (PECO) to study vs. elements neural coding. Muscle nerve activity (MSNA; microneurography) was measured in six...
Impaired cerebrovascular control in patients with heart failure reduced ejection fraction (HFrEF) has been attributed to cardiac impairment and exaggerated sympathetic-mediated cerebral vasoconstriction. The goal of this study was examine the effect muscle metaboreflex activation (MMA) on hemodynamics HFrEF under conditions preserved output. It hypothesized that reductions index blood flow conductance (CVCi) during MMA would be independent Middle velocity (MCAVmean; transcranial Doppler),...
Cardiac dysfunction in heart failure with reduced ejection fraction (HFrEF) may contribute to brain atrophy and cognitive decline beyond that which is typical of healthy ageing. This study tested the hypothesis HFrEF would be associated regionally-unique remodelling impaired performance independent age. Further, cardiac index clinical markers severity predict cognition age HFrEF, respectively. function morphology were assessed using magnetic resonance imaging young adults (24±6y), older...
A cumulative effect of reduced energy intake, increased oxygen consumption, and/or lipid oxidation could explain the fat loss associated with sprint interval exercise training (SIT). This study assessed effects acute (SIE) on subjective appetite, appetite-related peptides, and respiratory exchange ratio over 2 days. Eight men (25 ± 3 years, 79.6 9.7 kg, body 13% 6%; mean SD) completed experimental treatments: SIE recovery (SIEx) nonexercise control. Each 34-h treatment consisted consecutive...
Abstract The etiology of insulin resistance in Type 1 Diabetes (T1D) is unknown, however it affects approximately 20% T1D patients. Intramyocellular lipids (IMCL) have been identified as a mechanism resistance. We examined skeletal muscle rats to determine if alterations lipid metabolism were evident and whether aerobic exercise training improves IMCL To do so, 48 male Sprague-Dawley divided into control (C), sedentary diabetes (D) (DX) groups. Following multiple low-dose Streptozotocin...
This study tested the hypotheses that obesity-induced decrements in insulin-stimulated cerebrovascular vasodilation would be normalized with acute endothelin-1a receptor antagonism and treatment a physical activity intervention restores vasoreactivity to insulin through augmented nitric oxide synthase (NOS)-dependent dilation. Otsuka Long-Evans Tokushima Fatty rats were divided into following groups: 20 wk old food controlled (CON-20); free access (model of obesity, OB-20); 40 (CON-40);...
Key points It has been postulated that increased blood flow‐associated shear stress on endothelial cells is an underlying mechanism by which physical activity enhances insulin‐stimulated vasodilatation. This report provides evidence supporting the hypothesis exerts insulin‐sensitizing effects in vasculature and this based experiments vitro cells, ex vivo isolated arterioles humans. Given recognition vascular insulin signalling, associated enhanced microvascular perfusion, contributes to...
Insulin stimulates nerve arterial vasodilation through a nitric oxide (NO) synthase (NOS) mechanism. Experimental diabetes reduces vasa nervorum NO reactivity. Studies investigating hyperglycemia and typically omit insulin treatment use sedentary rats resulting in severe hyperglycemia. We tested the hypotheses that 1) insulin-treated experimental inactivity (DS rats) will attenuate insulin-mediated vasodilation, 2) deficits DS be overcome by concurrent exercise training (DX rats; 75-85% VO2...
Postmenopausal women represent the largest cohort of patients with heart failure preserved ejection fraction, and vascular dementia represents most common form in fraction. Therefore, we tested hypotheses that combination cardiac pressure overload (aortic banding [AB]) loss female sex hormones (ovariectomy [OVX]) impairs cerebrovascular control spatial memory.Female Yucatan miniswine were separated into 4 groups (n=7 per group): (1) control, (2) AB, (3) OVX, (4) AB-OVX. Pigs underwent OVX AB...
Heart failure (HF) is associated with increased large conduit artery stiffness and afterload resulting in stiffening of the coronary arteries. Perivascular adipose tissue (PVAT) advanced glycation end products (AGE) both promote arterial stiffness, yet mechanisms by which PVAT promotes efficacy exercise to prevent are unknown. We hypothesized that chronic continuous interval training would PVAT-mediated AGE secretion stiffness. Yucatan miniature swine were divided into four groups:...
Effective treatments preventing brain neuroinflammatory diseases are lacking. Resistance-exercise training (RT) ameliorates mild cognitive impairment (MCI), a forerunner to diseases. However, few studies have addressed the molecular basis by which RT abates MCI. Thus experiments were performed identify some changes occurring in response young, female Wistar rats. To induce MCI, intraventricular lipopolysaccharide (LPS) injections used increase dentate gyrus inflammation, reflected...
Background Cognitive impairment in the setting of heart failure with preserved ejection fraction remains poorly understood. Using aortic‐banded miniature swine displaying pathological features human fraction, we tested hypothesis that increased carotid artery stiffness and altered blood flow control are associated impaired memory independent decreased cardiac output. Furthermore, hypothesized chronic exercise prevents vascular restructuring preserves normal cognition fraction. Methods...
Purpose: Recent clinical data suggest an increasing prevalence of obesity and type 2 diabetes in adolescents, placing them at high risk developing diabetic retinopathy during adult working years. The present study was designed to characterize the early retinal microvascular alterations young Ossabaw pigs fed a Western diet, described as model metabolic syndrome genetically predisposed diabetes. Methods: Four-month-old miniature were divided into two groups, lean diet-induced obesity. Obese...
Insulin modulates vasomotor tone through vasodilator and vasoconstrictor signaling pathways. The purpose of the present work was to determine whether insulin-stimulated vasoconstriction is a pathophysiological phenomenon that can result from combination persistent insulin signaling, suppressed phosphatidylinositol-3 kinase (PI3K) activation, an ensuing relative increase in MAPK/endothelin-1 (ET-1) activity. First, we examined previously published our group where assessed changes lower-limb...