Assessments of Arterial Stiffness and Endothelial Function Using Pulse Wave Analysis

Conventionally, the assessments of endothelial function and arterial stiffness require different sets of equipment, making the inclusion of both tests impractical for clinical and epidemiological studies. Pulse wave analysis (PWA) provides useful information regarding the mechanical properties of the arterial tree and can also be used to assess endothelial function. PWA is a simple, valid, reliable, and inexpensive technique, offering great clinical and epidemiological potential. The current paper will outline how to measure arterial stiffness and endothelial function using this technique and include discussion of validity and reliability

The Use of Shear Rate-Diameter Dose-Response Curves As an Alternative to the Flow-Mediated Dilation Test

The brachial artery flow-mediated dilation test (FMD) is the non-invasive gold-standard used to test endothelial function. Reduced FMD precedes the development of atherosclerosis and provides an early marker for predicting future cardiovascular disease events. Although, this test is of high potential, it is somewhat limited by poor reproducibility. By utilizing hand warming and grip exercise combined with hierarchical linear modeling, shear rate-diameter dose-response curves may provide a novel and more accurate way to assess endothelial function in humans. Shear rate-diameter dose-response curves could potentially improve upon the traditional FMD measurement and serve as a superior clinical and research tool for assessing cardiovascular disease risk in a variety of populations. The current paper presents testable hypotheses and methodology for assessing the validity and reliability of an alternative to the current FMD test

Cardiovascular and Cerebral Hemodynamic Responses to Ego Depletion in a Pressurized Sporting Task

This study examined the effects of ego depletion on challenge and threat states and cerebral haemodynamic responses to a pressurized muscular endurance task requiring self-control. Following ethical approval, 58 participants (39 males, 19 females; Mage = 28 years, SD = 12) were randomly assigned to either an experimental or control group. Participants then completed self-report measures of trait anxiety and self-control. Next, the experimental group performed a written transcription task requiring self-control, while the control group transcribed the text normally. Finally, before the pressurized muscular endurance task, challenge and threat states were assessed using demand and resource evaluations and cardiovascular reactivity; while cerebral perfusion in Fp1 and Fp2 was assessed using near-infrared spectroscopy. The results supported the effectiveness of the self-control manipulation, with the experimental group transcribing fewer words, making more errors, and regulating their writing habits more than the control group. Although there were no differences between the groups in terms of muscular endurance performance or challenge and threat states, there was a significant interaction of time (pre vs. post) x group (experimental vs. control) in cerebral perfusion. These findings suggest that ego depletion might not influence challenge and threat states, but may lead to reduced cerebral perfusion. As such, cerebral perfusion may be a novel marker which could be used to assess ego depletion

Strength and forearm volume differences in boulderers and sport climbers

Summary – Twenty-eight participants were divided into three groups: control (n=10), sport climbers (n=9) and boulderers (n=9) to investigate the determinants of grip strength between climbing disciplines. Forearm volume (FAV) was measured using water displacement method. Maximal volitional contraction (MVC) was assessed using an open crimp grip on a climbing specific fingerboard apparatus. There were no significant differences in FAV between disciplines. However, there was a significant main effect for MVC and MVC/FAV across all groups. Boulderers had higher MVC than sport (MD=7.5 CI=1.8-13.2) and controls (MD=17.7 CI= 11.9-23.6) and sport climbers was higher than controls (MD= 10.2 CI = 4.5-15.9. The findings suggest that the greater MVC seen in boulderers and sport climbers may be a result of neural adaptations, not muscular hypertrophy

The Importance of Velocity Acceleration to Flow-Mediated Dilation

The validity of the flow-mediated dilation test has been questioned due to the lack of normalization to the primary stimulus, shear stress. Shear stress can be calculated using Poiseuille's law. However, little attention has been given to the most appropriate blood velocity parameter(s) for calculating shear stress. The pulsatile nature of blood flow exposes the endothelial cells to two distinct shear stimuli during the cardiac cycle: a large rate of change in shear at the onset of flow (velocity acceleration), followed by a steady component. The parameter typically entered into the Poiseuille's law equation to determine shear stress is time-averaged blood velocity, with no regard for flow pulsatility. This paper will discuss (1) the limitations of using Posieuille's law to estimate shear stress and (2) the importance of the velocity profile—with emphasis on velocity acceleration—to endothelial function and vascular tone

The Importance of Velocity Acceleration to Flow-Mediated Dilation

The validity of the flow-mediated dilation test has been questioned due to the lack of normalization to the primary stimulus, shear stress. Shear stress can be calculated using Poiseuille's law. However, little attention has been given to the most appropriate blood velocity parameter(s) for calculating shear stress. The pulsatile nature of blood flow exposes the endothelial cells to two distinct shear stimuli during the cardiac cycle: a large rate of change in shear at the onset of flow (velocity acceleration), followed by a steady component. The parameter typically entered into the Poiseuille's law equation to determine shear stress is time-averaged blood velocity, with no regard for flow pulsatility. This paper will discuss (1) the limitations of using Posieuille's law to estimate shear stress and (2) the importance of the velocity profile—with emphasis on velocity acceleration—to endothelial function and vascular tone

A Metabolically Healthy Profile Is a Transient Stage When Exercise and Diet Are Not Supervised: Long-Term Effects in the EXERDIET-HTA Study

Metabolically unhealthy obesity (MUO) is a regular state in people with primary hypertension (HTN), obesity, and who are physically inactive. To achieve and maintain a metabolically healthy overweight/obese (MHO) state should be a main treatment goal. The aims of the study were (1) to determine differences in metabolic profiles of overweight/obese, physically inactive individuals with HTN following a 16-week (POST) supervised aerobic exercise training (SupExT) intervention with an attentional control (AC) group, and (2) to determine whether the changes observed were maintained following six months (6 M) of unsupervised time. Participants (n = 219) were randomly assigned into AC or SupExT groups. All participants underwent a hypocaloric diet. At POST, all participants received diet and physical activity advice for the following 6 M, with no supervision. All measurements were assessed pre-intervention (PRE), POST, and after 6 M. From PRE to POST, MUO participants became MHO with improved (p < 0.05) total cholesterol (TC, ∆ = −12.1 mg/dL), alanine aminotransferase (∆ = −8.3 U/L), glucose (∆ = −5.5 mg/dL), C-reactive protein (∆ = −1.4 mg/dL), systolic blood pressure (SBP), and cardiorespiratory fitness (CRF) compared to unhealthy optimal cut-off values. However, after 6 M, TC, glucose, and SBP returned to unhealthy values (p < 0.05). In a non-physically active population with obesity and HTN, a 16-week SupExT and diet intervention significantly improves cardiometabolic profile from MUO to MHO. However, after 6 M of no supervision, participants returned to MUO. The findings of this study highlight the need for regular, systematic, and supervised diet and exercise programs to avoid subsequent declines in cardiometabolic health.P.C., A.M.A.-B., and I.G.-A. were supported by the Basque Government with predoctoral grants. This study was supported by the University of the Basque Country (EHU14/08, PPGA18/15)