Publications by authors named "Jem L Cheng"

Article Synopsis
  • The study investigates the relationship between sex, gender identity, and gender expression on cardiovascular disease risk factors in young adults, as previous research has not focused on these aspects.
  • Results show that males have elevated blood pressure, arterial stiffness, and better endothelial function compared to females, with no significant differences found based on gender expression.
  • The findings suggest that sex and gender identity influence cardiovascular health, while gender expression does not, indicating a need for further research in gender-diverse populations.
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Purpose: The purpose of this study is to compare the effects of 8 wk of no intervention (CON), lower limb heat therapy (HEAT), moderate-intensity exercise training (EX), or combined training and therapy (HEATEX) in young, healthy recreationally active adults.

Methods: Sixty participants (23 ± 3 yr, 30 females) were randomly allocated into CON ( n = 15), HEAT ( n = 15), EX ( n = 14), or HEATEX ( n = 16). The primary outcome was vascular function, assessed through brachial artery flow-mediated dilation tests.

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Historical exclusion of females in research has been, in part, due to the perceived influence of natural menstrual (NAT) and oral contraceptive pill (OCP) cycles on vascular outcomes. NAT and OCP cycle phases may influence brachial artery (BA) endothelial function, however, findings are mixed. Minimal research has examined arterial stiffness, smooth muscle, and lower limb endothelial function.

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Habitual short sleep durations are associated with several cardiovascular diseases. Experimental research generally supports these findings as metrics of arterial function are impaired after complete deprivation of sleep and after longer periods of partial sleep restriction. The acute influence of a single instance of partial sleep restriction (PSR), however, has not been defined.

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Purpose: Recent studies suggest that episodic increases in cerebral blood flow (CBF) may contribute to the improvement in brain health associated with exercise training. Optimising CBF during exercise may enhance this benefit. Water immersion in ~ 30-32 °C augments CBF at rest and during exercise; however, the impact of water temperature on the CBF response has not been investigated.

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Flow-mediated dilation (FMD) provides a valid bioassay of vascular function in humans. Although water immersion induces hemodynamic effects that modify brachial artery shear stress, it is unclear whether water-based exercise modifies FMD. We hypothesized that exercise in 32°C water would decrease brachial artery shear and FMD relative to land-based exercise, whereas exercise in 38°C would increase brachial shear and FMD.

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Regular exposure to passive heat stress improves vascular function, but the optimal heating prescription remains undefined. Local limb heating is more feasible than whole body heating, but the evidence demonstrating its efficacy is lacking. The purpose of this study was to determine whether acute improvements in vascular function can be achieved with lower limb heating in 16 young healthy individuals (8 female, 8 male).

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Aging is associated with increased risk of cardiovascular and cerebrovascular events, which are preceded by early, negative remodeling of the vasculature. Low physical activity is a well-established risk factor associated with the incidence and development of disease. However, recent physical activity literature indicates the importance of considering the 24-h movement spectrum.

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The aim of this study was to compare the acute cardiometabolic and perceptual responses between local and whole-body passive heating. Using a water-perfused suit, 10 recreationally active males underwent three 90 min conditions: heating of the legs with upper-body cooling (LBH), whole-body heating (WBH) and exposure to a thermoneutral temperature (CON). Blood samples were collected before and up to 3 h post-session to assess inflammatory markers, while a 2 h oral glucose tolerance test was initiated 1 h post-session.

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Sleep is critical for the maintenance of physiological homeostasis and, as such, inadequate sleep beckons a myriad of pathologies. Sleep deprivation is a growing health concern in contemporary society since short sleep durations are associated with increased cardiovascular disease risk and atherosclerotic plaque development. Vascular endothelial dysfunction is an antecedent to atherosclerosis and cardiovascular disease.

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Objective: To examine longitudinal changes in traditional and non-traditional risk factors for cardiovascular disease in individuals with cerebral palsy and to investigate relationships between age, Gross Motor Function Classification System (GMFCS) and risk of cardiovascular disease.

Methods: Individuals with cerebral palsy (n = 28 of 53 eligible participants; GMFCS levels I-V; follow-up mean age 35.1 years (standard deviation (SD) 14.

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New Findings: What is the central question of this study? What is the effect of altered shear stress pattern, with or without concurrent neurohumoral and metabolic activation, on the acute endothelial function response assessed via brachial artery flow-mediated dilatation? What is the main finding and its importance? Despite generating distinctive shear stress patterns (i.e. increases in anterograde only, anterograde only with neurohumoral and metabolic activation, and both anterograde and retrograde), similar acute improvements were observed in the brachial artery flow-mediated dilatation response in all conditions, indicating that anterograde and/or turbulent shear stress might be the essential element to induce acute increases in endothelial function.

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In addition to its role as an environmental stressor, scientists have recently demonstrated the potential for heat to be a therapy for improving or mitigating declines in arterial health. Many studies at both ends of the scientific controls spectrum (tightly controlled, experimental vs. practical) have demonstrated the beneficial effects of heating on microvascular function (e.

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What is the central question of this study? Carotid artery longitudinal wall motion (CALM) is a bidirectional forward and backward motion of the arterial wall; however, there is no evidence in humans for what controls CALM despite proposals for pulse pressure, left ventricular motion and shear rate. What is the main finding and its importance? Carotid artery longitudinal wall motion responses were heterogeneous when manipulating sympathetic activation and endothelium-independent vasodilatation, leading to non-significant group responses. However, individual CALM responses were associated with left ventricular rotation and shear rate.

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The cardiovascular profile of postural orthostatic tachycardia syndrome + Ehlers-Danlos syndrome hypermobility type (POTS + EDSIII) has not been described, despite suggestions that it plays a role in orthostatic intolerance. We studied nine individuals diagnosed with POTS + EDSIII and found that the arterial stiffness and cardiac profiles of patients with POTS + EDSIII were comparable to those of age- and sex-matched controls, suggesting an alternate explanation for orthostatic intolerance.

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