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Background: Repetitive Strain Injury (RSI) is a major problem in nowadays health care and creates high financial costs and personal distress. Average prevalence rates in the Netherlands vary from 20-40% of the working population. Insight into the patho-physiological mechanism of RSI is important in order to establish adequate treatment and prevention programs. Objective: The aim of this study was to gain insight in muscle oxygen consumption (mVO2), blood flow (BF), and reoxygenation (ReOx) in the forearm of computer workers with stage III Repetitive Strain Injury (RSI). Method: We have used continuous wave infrared spectroscopy (NIRS) to measure these variables. Measurements were conducted on the extensor and flexor muscle in both arms as well in RSI-patients (n=10) as in control subjects (n=21). A protocol of increased isometric repetitive contraction in a handgrip ergonometer was used with increasing levels of strength. Results: mVO2 in the extensor muscle in RSI-subjects (dominant side) was increased compared to control subjects and compared to the non-dominant side (p

Women with the metabolic syndrome are prone to develop atherosclerosis and subsequently cardiovascular diseases.

See related article, pp 1145–1150 In reductionist times, it is refreshing to appreciate the creativity of apparently “simple” technical approaches coupled with clever experimental design. The study of Jiang et al1 evokes Harvey2 in its manipulation of human vascular behavior using a “ligature,” coupled with careful visual appraisal, to examine the impact of pressure on artery diameter responses. They modified a technique introduced by Celermajer et al3 involving inflation of a pneumatic cuff placed around the forearm to high pressure (for ≈5 minutes) to induce distal limb ischemia. Cuff deflation is associated with a large increase in blood flow through the upstream radial or brachial artery,4 which, in turn, induces a “flow-mediated” dilation (FMD).3 This, in turn, has been attributed to the release of vasodilator paracrines such as NO from the endothelium, as a consequence of shear stress–mediated signal transduction.5 The FMD test has become a popular noninvasive test of endothelial function, in part because it predicts future cardiovascular events.6,7 The kinetics of the vasodilator response after cuff deflation in the FMD test have always been quizzical in that the peak blood …

Corrigendum to “Local and systemic effects of leg cycling training on arterial wall thickness in healthy humans” [Atherosclerosis 229 (2) (2013) 282e286] Dick H.J. Thijssen *, Ellen A. Dawson , Inge C.L. van den Munckhof , Gurpreet K. Birk , N. Timothy Cable , Daniel J. Green a,c Research Institute for Sport and Exercise Science, Liverpool John Moores University, Tom Reilly Building, Byrom Street, Liverpool L3 3AF, United Kingdom Department of Physiology, Radboud University Nijmegen Medical Centre, The Netherlands c School of Sport Science, Exercise and Health, The University of Western Australia, Crawley, Western Australia 6009, Australia

Retrograde shear rate (SR) in the brachial artery (BA) is associated with endothelial dysfunction; a precursor to atherosclerosis. The BA does not typically manifest clinical atherosclerosis, whereas the superficial femoral artery (SFA) is more prone to developing plaque. Examine whether the impact of incremental levels of retrograde SR differs between atherosclerosis‐prone (i.e., SFA) and ‐resistant vessels (i.e., BA) in healthy men. Thirteen healthy young men reported three times to the laboratory. We examined BA flow‐mediated dilation (FMD) before and after 30‐min exposure to cuff inflation around the forearm at 0, 30, and 60 mmHg, to manipulate retrograde SR. Subsequently, the 30‐min intervention was repeated in the SFA, using the same cuff pressure as in the forearm. Order of testing (vessel and intervention) was randomized among subjects. We found a dose‐dependent increase in retrograde SR with 30 and 60 mmHg cuff inflation, which was present in both the BA and SFA (all P < 0.05). BA and SFA FMD decreased after the 30‐min intervention (“time”: P = 0.012), and this was dependent on cuff pressure (“cuff × time”: P = 0.024). A significant decrease in FMD was observed after 60 mmHg only and this change was similarly present in both arteries (“time × artery”: P = 0.227). Moreover, the BA and SFA demonstrate a similar relationship between changes in retrograde SR and FMD (r = 0.498 and 0.475, respectively). Our study demonstrates that acute exposure to an increase in retrograde shear leads to comparable decreases in FMD in atherosclerotic‐prone and ‐resistant conduit arteries in humans., We examined whether the impact of incremental levels of retrograde shear rate differs between atherosclerosis‐prone (i.e., superficial femoral artery) and ‐resistant vessels (i.e., brachial artery) in healthy men. Our study demonstrates that acute exposure to an increase in retrograde shear leads to comparable decreases in flow‐mediated dilation in atherosclerotic‐prone and ‐resistant conduit arteries in humans.

Background: The high sensitivity C Reactive Protein (hsCRP) which was once considered a risk marker associated with cardiovascular diseases is increasingly considered as an independent risk factor which has atherogenic potential. Objectives: To determine whether a dose response relationship exists between exercise intensity and hsCRP in sedentary individuals. Methods/design: A four year randomized, active controlled, parallel group, outcome assessor blind, multiple arm trial. Procedure: 98 sedentary (otherwise healthy) individuals with a baseline hsCRP of more than 1mg/L and less than 15mg/L were randomly allocated to one of the four groups (Control, and three exercise groupswith escalating intensities of exercise). Three exercise groups were administered an exercise program at 50–60%, 60–70% and 70–80% based on heart rate reserve method, respectively for eight weeks. Concentration of hsCRP was measured at baseline andafter eightweeksusing immunoturbidimetry. The secondary outcome measures in this trial were peak oxygen uptake, waist circumference, fat percentage and body mass index. Results: Participants had amean (range) age of 23.3 (18–36) and a mean (range) body mass index of 26.6 (17.1–36.8). The hsCRP data was rank transformed as it did not follow normal distribution. The results indicated that there was no dose response relationship between exercise intensity and reduction in hsCRP (F=1.603, p=0.19). After removing six participants who had an increase in hsCRPofmore than30% frombaseline after eightweeks,we found a significant reduction of 38% in participantswhowere in the 60–70% intensity and about 25% in participants with 50–60 and 70–80% intensity (F=3.63, p

Introduction: Exercise training of the lower limbs mediates localised conduit and resistance artery adaptations in the active region and systemic adaptations in the upper limbs. These changes to the vasculature are largelymediated through elevations in shear stress. Whether microcirculatory vascular responses to lower limb training occur systemically, and whether shear stress contributes to such adaptations, is currently unknown. Methods: Nine subjects completed an 8-week cycle ergometer training study, with unilateral cuff inflation around the forearm to unilaterally manipulate upper limb blood flow and shear stress during each exercise bout. To test skin microvascular function at 0, 4 and 8 weeks of exercise training, we measured laser-Doppler skin flux in response to localised disk heating at 33, 42 and 44 ◦C. Cutaneous vascular conductance was derived from skin flux and blood pressure values. Results: Acutely, the onset of cycling increased skin flux (12.1±4.1 to 131.7±35.0 PU) and temperature (31.7±0.4 to 33.6±0.9 ◦C), whilst in the cuffed arm (60mmHg) skin flux (11.91±2.22 to 52.92PU) and temperature (31.5±0.3 to 31.7±0.8 ◦C) responses were attenuated or absent (2-way ANOVA interaction-effect; both P

Age is one of the most important risk factors for cardiovascular disease. For example, a 30-year-old male smoker with untreated hypertension, diabetes, dyslipidemia, and a strong family history of premature coronary heart disease (CHD) would have a 10-year coronary heart disease event rate of only 16% (“intermediate risk”) by Framingham criteria; however, given exactly the same risk profile for a 60-year-old, the risk climbs to >50%. Aging, particularly sedentary aging, leads not only to the development of atherosclerosis but also to ventricular and arterial stiffening.1 This reduces functional capacity and contributes to chronic diseases of the elderly, such as systolic hypertension or heart failure with a preserved ejection fraction. In the search for the underlying mechanism for this effect of sedentary aging, one common feature that has been identified universally in older men is an increased baseline vascular tone,2 which has both hemodynamic and metabolic consequences.3 Although this age-related increase in vascular tone is mediated in part by a chronically elevated sympathetic α-adrenergic vasoconstriction,2 endothelial function also plays a critical role in vascular stability and the regulation of vasomotor function. The endothelium regulates vascular tone through the release of dilator and constrictor substances. Endothelin (ET)-1 is the most potent endothelium-derived constricting factor and influences peripheral vascular tone by interacting with ETA and ETB receptors on smooth muscle cells and the endothelium.4 Several animal studies have examined the profound effects of vascular aging on the ET-1 pathway and support a central role for ET-1 to explain the age-related increase in vascular tone.5–7 In the present issue of Hypertension , Van Guilder et al8 present new and important information regarding the role of aging and physical fitness on the vasomotor effects of ET-1. Using a cross-sectional design in a small but carefully studied …

Fysieke inactiviteit is geassocieerd met het ontstaan van chronische aandoeningen, zoals type 2 diabetes mellitus en cardiovasculaire ziekten. Regelmatig bewegen is een effectieve manier om deze nadelige gevolgen tegen te gaan, maar de onderliggende mechanismen zijn grotendeels onbekend. Om meer inzicht in deze mechanismen te krijgen, hebben wij met behulp van genexpressie-microarrays het expressieniveau van alle bekende genen in de spier bepaald bij mensen, na fysieke deconditionering versus training van de benen.

Contains fulltext : 125640.pdf (Publisher’s version ) (Open Access) Exposure of the arterial wall to retrograde shear acutely leads to endothelial dysfunction and chronically contributes to a proatherogenic vascular phenotype. Arterial stiffness and increased pressure from wave reflections are known arbiters of blood flow in the systemic circulation and each related to atherosclerosis. Using distal external compression of the calf to increase upstream retrograde shear in the superficial femoral artery (SFA), we examined the hypothesis that changes in retrograde shear are correlated with changes in SFA stiffness and pressure from wave reflections. For this purpose, a pneumatic cuff was applied to the calf and inflated to 0, 35, and 70 mmHg (5 min compression, randomized order, separated by 5 min) in 16 healthy young men (23 +/- 1 years of age). Doppler ultrasound and wave intensity analysis was used to measure SFA retrograde shear rate, reflected pressure wave intensity (negative area [NA]), elastic modulus (Ep), and a single-point pulse wave velocity (PWV) during acute cuff inflation. Cuff inflation resulted in stepwise increases in retrograde shear rate (P < 0.05 for main effect). There were also significant cuff pressure-dependent increases in NA, Ep, and PWV across conditions (P < 0.05 for main effects). Change in NA, but not Ep or PWV, was associated with change in retrograde shear rate across conditions (P < 0.05). In conclusion, external compression of the calf increases retrograde shear, arterial stiffness, and pressure from wave reflection in the upstream SFA in a dose-dependent manner. Wave reflection intensity, but not arterial stiffness, is correlated with changes in peripheral retrograde shear with this hemodynamic manipulation. 01 juli 2013

To the editor: With great interest, we read the articles of a recent issue of Heart addressing the important role of abdominal obesity in relation to cardiovascular risk and the metabolic syndrome.1 2 The metabolic syndrome, considered the ailment of the 20th century, emerges from clustering and interactions of multiple cardiovascular risk factors affecting a large proportion of the population. The presence of the metabolic syndrome in children is of particular interest given the rapid and alarming increase in prevalence in the past …

Contains fulltext : 80903thijssen.pdf (Publisher’s version ) (Open Access)

Contains fulltext : 169656.pdf (Publisher’s version ) (Open Access) BACKGROUND: Healthy athletes demonstrated increased B-type natriuretic peptide (BNP) concentrations following exercise, but it is unknown whether these responses are exaggerated in individuals with cardiovascular risk factors (CVRF) or disease (CVD). We compared exercise-induced increases in BNP between healthy controls (CON) and individuals with CVRF or CVD. Furthermore, we aimed to identify predictors for BNP responses. METHODS: Serum BNP concentrations were measured in 191 participants (60+/-12yrs) of the Nijmegen Marches before (baseline) and immediately after 4 consecutive days of walking exercise (30-50km/day). CVRF (n=54) was defined as hypertension, hypercholesterolemia, obesity or smoking and CVD (n=55) was defined as a history of myocardial infarction, heart failure, atrial fibrillation or angina pectoris. RESULTS: Individuals walked 487+/-79min/day at 65+/-10% of their maximum heart rate. Baseline BNP concentrations were higher for CVD (median: 28.1pg/ml; interquartile range: 13-50, p0.05). Predictors for post-exercise BNP (R2=0.77) were baseline BNP, beta-blocker use and age. CONCLUSION: Prolonged moderate-intensity walking exercise increases BNP concentrations in CVD participants, but not in CVRF and CON. BNP increases were small, and did not accumulate across consecutive days of exercise. These findings suggest that prolonged walking exercise for multiple consecutive days is feasible with minimal effect on myocardial stretch, even for participants with CVD.

Contains fulltext : 171793.pdf (Publisher’s version ) (Open Access) Brachial artery Flow Mediated Dilation (FMD) is widely used as a non-invasive measure of endothelial function. Adherence to expert consensus guidelines on FMD measurement has been found to be of vital importance to obtain reproducible data. This article lists the literature data which was considered in the development of a tool to aid in the objective judgement of the extent to which published studies adhered to expert guidelines for FMD measurement. Application of this tool in a systematic review of FMD studies (http://dx.doi.org/10.1016/j.atherosclerosis.2016.03.011) (Greyling et al., 2016 [1]) indicated that adherence to expert consensus guidelines is strongly correlated to the reproducibility of FMD data. 01 september 2016

Introduction: Oxidative stress (OS) and mitochondrial dysfunction are implicated in the pathogenesis of a number of metabolic diseases. OS occurs when there is an imbalance between the pro-oxidant/antioxidant homeostasis, leading to an increased generation of reactive oxidant species (ROS) with resultant cellular dysfunction. It is becoming apparent that increased ROS generation may be attributable to secondary mitochondrial dysfunction as a consequence of disease pathophysiology. Mitochondrial dysfunction occurs as a result of oxidative damage from enhanced ROS generation as well as the accumulation of toxic metabolites in some metabolic diseases.\ud Areas covered: The present review will discuss evidence of OS and mitochondrial dysfunction in phenylketonuria (PKU), lysosomal storage disorders (LSDs), and peroxisomal disorders. In addition, potential adjunct therapies which have the potential to enhance mitochondrial functioning and mitigate OS will be explored. The databases utilized for this review were Pubmed and the Wed of science, with inclusive dates, 1988–2020.\ud Expert opinion: There is an un-unified approach in the treatment of metabolic diseases. Agents including augmenters of mitochondrial function, antioxidants, and activators of mitochondrial biogenesis, may be beneficial. However, although successful in some cases, these adjunct therapies have yet to be incorporated into the clinical-management of metabolic diseases.

Item does not contain fulltext PURPOSE: We performed two experiments to determine whether cutaneous microvascular adaptations in response to repeated core temperature (Tc) elevation are mediated by increases in skin blood flow (SkBF) and/or skin temperature. METHODS: Healthy subjects participated for 8 wk in thrice-weekly bouts of 30-min lower limb heating (40 degrees C). In study 1, both forearms were "clamped" at basal skin temperature throughout each heating bout (n = 9). Study 2 involved identical lower limb heating, with the forearms under ambient conditions (unclamped, n = 10). In both studies, a cuff was inflated around one forearm during the heating bouts to assess the contribution of SkBF and temperature responses. We assessed forearm SkBF responses to both lower limb (systemic reflex) heating and to local heating of the forearm skin, pre- and postintervention. RESULTS: Acutely, lower limb heating increased Tc (study 1, 0.63 degrees C +/- 0.15 degrees C; study 2, 0.69 degrees C +/- 0.19 degrees C; P < 0.001) and forearm SkBF (study 1, 0.13 +/- 0.03 vs 1.52 +/- 0.51; study 2, 0.14 +/- 0.01 vs 1.17 +/- 0.38 cutaneous vascular conductance (CVC); P < 0.001), with skin responses significantly attenuated in the cuffed forearm (P < 0.01). SkBF responses to local heating decreased in study 1 (clamped forearms; week 0 vs week 8, 1.46 +/- 0.52 vs 0.99 +/- 0.44 CVC; P < 0.05), whereas increases occurred in study 2 (unclamped; week 0 vs week 8, 1.89 +/- 0.57 vs 2.27 +/- 0.52 CVC; P < 0.05). Cuff placement abolished local adaptations in both studies. CONCLUSIONS: Our results indicate that repeated increases in SkBF and skin temperature result in increased skin flux responses to local heating, whereas repeated increases in SkBF in the absence of change in skin temperature induced the opposite response. Repeated increases in Tc induce intrinsic microvascular changes, the nature of which are dependent upon both SkBF and skin temperature. 01 november 2014

Aims: The aim of this study was to examine physical activity and sedentary behaviour characteristics of ambulatory and community-dwelling patients with dementia compared to cognitively healthy age-, sex- and weight-matched controls. Methods: In this cross-sectional study, we included community-dwelling dementia patients (n = 45, age 79.6 ± 5.9 years, Mini-Mental State Examination [MMSE] 22.8 ± 3.2) and matched controls (n = 49, age 80.0 ± 7.7 years, MMSE 29.0 ± 1.2). Participants wore a wrist accelerometer for 7 days to assess sedentary time, sedentary bout duration and time spent in very light, light-to-moderate and moderate-to-vigorous physical activities. Results: Relative sedentary time and sedentary bout duration was significantly higher in dementia patients than in controls (median [interquartile range] 57% [49–68] vs. 55% [47–59] and 18.3 [16.4–21.1] min vs. 16.6 [15.3–18.4] min, p = 0.042 and p = 0.008, respectively). In addition, dementia patients spent a lower percentage of their waking time in light-to-moderate and moderate-to-vigorous intensity physical activities (20% [15–23] vs. 22% [18–25] and 5% [2–10] vs. 10% [5–13], p = 0.017 and p = 0.001, respectively). Conclusion: We revealed that dementia patients are more sedentary and perform less physical activity than cognitively healthy controls. This may have clinically important consequences, given the observation that sedentary behaviour and little physical activity independently predict all-cause mortality and morbidity.

Contains fulltext : 152164.pdf (Publisher’s version ) (Open Access) INTRODUCTION: Physical fitness is an important prognostic factor in heart failure (HF). To improve fitness, different types of exercise have been explored, with recent focus on high-intensity interval training (HIT). We comprehensively compared effects of HIT versus continuous training (CT) in HF patients NYHA II-III on physical fitness, cardiovascular function and structure, and quality of life, and hypothesize that HIT leads to superior improvements compared to CT. METHODS: Twenty HF patients (male:female 19:1, 64+/-8 yrs, ejection fraction 38+/-6%) were allocated to 12-weeks of HIT (10*1-minute at 90% maximal workload-alternated by 2.5 minutes at 30% maximal workload) or CT (30 minutes at 60-75% of maximal workload). Before and after intervention, we examined physical fitness (incremental cycling test), cardiac function and structure (echocardiography), vascular function and structure (ultrasound) and quality of life (SF-36, Minnesota living with HF questionnaire (MLHFQ)). RESULTS: Training improved maximal workload, peak oxygen uptake (VO2peak) related to the predicted VO2peak, oxygen uptake at the anaerobic threshold, and maximal oxygen pulse (all P

Contains fulltext : 172865.pdf (Publisher’s version ) (Open Access) BACKGROUND: Brachial artery FMD is widely used as a non-invasive measure of endothelial function. Adherence to expert guidelines is believed to be of vital importance to obtain reproducible measurements. We conducted a systematic review of studies reporting on the reproducibility of the FMD in order to determine the relation between adherence to current expert guidelines for FMD measurement and its reproducibility. METHODS: Medline-database was searched through July 2015 and 458 records were screened for FMD reproducibility studies reporting the mean difference and variance of repeated FMD measurements. An adherence score was assigned to each of the included studies based on reported adherence to published guidelines on the assessment of brachial artery FMD. A Typical Error Estimate (TEE) of the FMD was calculated for each included study. The relation between the FMD TEE and the adherence score was investigated by means of Pearson correlation coefficients and multiple linear regression analysis. RESULTS: Twenty-seven studies involving 48 study groups and 1537 subjects were included in the analyses. The adherence score ranged from 2.4 to 9.2 (out of a maximum of 10) and was strongly and inversely correlated with FMD TEE (adjusted R2 = 0.36, P < 0.01). Use of automated edge-detection software, continuous diameter measurement, true peak diameter for %FMD calculation, a stereostatic probe holder, and higher age emerged as factors associated with a lower FMD TEE. CONCLUSIONS: These data demonstrate that adherence to current expert consensus guidelines and applying contemporary techniques for measuring brachial artery FMD decreases its measurement error.

Item does not contain fulltext Carotid artery intima-medial thickness (cIMT) represents a popular measure of atherosclerosis and is predictive of future cardiovascular and cerebrovascular events. Although older age is associated with a higher cIMT, little is known about whether this increase in cIMT follows a linear relationship with age or it is affected under influence of cardiovascular diseases (CVD) or CVD risk factors. We hypothesize that the relationship between cIMT and age is nonlinear and is affected by CVD or risk factors. A systematic review of studies that examined cIMT in the general population and human populations free from CVD/risk factors was undertaken. The literature search was conducted in PubMed, Scopus, and Web of Science. Seventeen studies with 32 unique study populations, involving 10,124 healthy individuals free from CVD risk factors, were included. Furthermore, 58 studies with 115 unique study populations were included, involving 65,774 individuals from the general population (with and without CVD risk factors). A strong positive association was evident between age and cIMT in the healthy population, demonstrating a gradual, linear increase in cIMT that did not differ between age decades (r = 0.91, P < 0.001). Although populations with individuals with CVD demonstrated a higher cIMT compared to populations free of CVD, a linear relation between age and cIMT was also present in this population. Our data suggest that cIMT is strongly and linearly related to age. This linear relationship was not affected by CVD or risk factors.

Background Remote ischaemic preconditioning (rIPC) may improve cardiac/cerebrovascular outcomes of ischaemic events. Ischaemic damage caused by cardiovascular/cerebrovascular disease are primary causes of mortality in type 2 diabetes mellitus (T2DM). Due to the positive effects from a bout of rIPC within the vasculature, we explored if daily rIPC could improve endothelial and cerebrovascular function. The aim of this pilot study was to obtain estimates for the change in conduit artery and cerebrovascular function following a 7-day rIPC intervention. Methods Twenty-one patients with T2DM were randomly allocated to either 7-day daily upper-arm rIPC (4 × 5 min 220 mmHg, interspaced by 5-min reperfusion) or control. We examined peripheral endothelial function using flow mediated dilation (FMD) before and after ischemia-reperfusion injury (IRI, 20 min forearm ischaemic-20 min reperfusion) and cerebrovascular function, assessed by dynamic cerebral autoregulation (dCA) at three time points; pre, post and 8 days post intervention. Results For exploratory purposes, we performed statistical analysis on our primary comparison (pre-to-post) to provide an estimate of the change in the primary and secondary outcome variables. Using pre-intervention data as a covariate, the change from pre-post in FMD was 1.3% (95% CI: 0.69 to 3.80; P = 0.09) and 0.23 %cm/s %/mmHg mmHg/% (−0.12, 0.59; P = 0.18) in dCA normalised gain with rIPC versus control. Based upon this, a sample size of 20 and 50 for FMD and normalised gain, respectively, in each group would provide 90% power to detect statistically significant (P Conclusion We provide estimates of sample size for a randomised control trial exploring the impact of daily rIPC for 7 days on peripheral endothelial and cerebrovascular function. The directional changes outline from our pilot study suggest peripheral endothelial function can be enhanced by daily rIPC in patients with T2DM.

Item does not contain fulltext AIM: Advanced age is associated with vascular endothelial dysfunction, characterized by reductions in the endothelium-dependent vasodilation of the conduit and resistance arteries, in part, from decreased nitric oxide bioavailability. Although vascular smooth muscle function (SMF), assessed by responsiveness to an exogenous nitric oxide donor, is typically reported to be intact, many of these studies are limited by a small sample size. Therefore, the purpose of this meta-analysis is to systematically review and determine whether vascular SMF is different between older versus young healthy individuals. DESIGN: We conducted a systematic search of MEDLINE, Cochrane and Scopus, since their inceptions until January 2014, for articles evaluating SMF in the brachial artery and/or resistance arteries (BASMF and RASMF, respectively), as assessed by the endothelium-independent vasodilator response to exogenous nitric oxide donors in older (>/=60 years) and young (

BACKGROUND & AIMS: Dietary flavonoids, such as those present in black tea, are associated with reduced risk of cardiovascular disease (CVD), possibly through improving nitric oxide (NO) mediated vascular function. The aim of this study was to examine the effect of acute black tea ingestion on cutaneous microvascular function. METHODS: Twenty healthy participants (58 ± 5 y, 9 men) attended two experimental trials (tea, placebo), 7-days apart in a randomised, controlled, double-blind, cross-over design. Participants ingested a single dose of 200 ml black tea or placebo, followed by assessment of forearm cutaneous perfusion using laser-Doppler flowmetry (LDF) using three distinct heating protocols, enabling us to distinguish between axon- and endothelium-dependent vasodilation: 1. rapid 42°C, 2. rapid 39°C and 3. gradual 42°C. On the contralateral arm, full-field laser perfusion imaging (FLPI) was used to assess forearm perfusion during gradual 42°C. Data were presented as cutaneous vascular conductance (CVC; flux/mean arterial pressure, MAP) and CVC expressed as a percentage of maximal CVC (%CVCmax). RESULTS: Rapid local heating to 39°C or 42°C demonstrated no effect of tea for flux, CVC or %CVCmax (all P > 0.05). Gradual local heating to 42 °C, however, produced a higher skin blood flow following black tea ingestion for absolute CVC (P = 0.04) when measured by LDF, and higher absolute flux (P

Contains fulltext : 229801.pdf (Publisher’s version ) (Closed access) Atrial fibrillation (AF) is the most common cardiac arrhythmia, characterized by irregular atrial activity. AF is related to increased risk of thromboembolic events, heart failure, and premature mortality. Recent advances in our understanding of its pathophysiology include a potentially central role for inflammation and presence of cardiovascular risk factors. The role of physical activity and exercise in the development and progression of AF, however, are not yet fully understood. Physical activity is protective for modifiable cardiovascular risk factors, including those associated with AF. Indeed, emerging research has demonstrated beneficial effects of exercise on AF-specific outcomes, including AF recurrence postablation. Counterintuitively, the prevalence of AF in veteran endurance athletes seems higher compared with the general population. In this review, we discuss the novel evidence and underlying mechanisms underpinning the role of exercise as medicine in the development and management of AF but also the counterintuitive detrimental role of excessive endurance exercise. Finally, we advocate regular (but not long-term high-intensity endurance) exercise training as a safe and effective strategy to reduce the risk of incident AF and to minimize the associated risk of secondary cardiovascular events.

Item does not contain fulltext Reperfusion is essential for ischemic tissue survival, but causes additional damage to the endothelium [i.e., ischemia-reperfusion (I/R) injury]. Ischemic preconditioning (IPC) refers to short repetitive episodes of ischemia that can protect against I/R. However, IPC efficacy attenuates with older age. Whether physical inactivity contributes to the attenuated efficacy of IPC to protect against I/R injury in older humans is unclear. We tested the hypotheses that lifelong exercise training relates to 1) attenuated endothelial I/R and 2) maintained IPC efficacy that protects veteran athletes against endothelial I/R. In 18 sedentary male individuals (SED, 20 yr, 63 +/- 7 yr) and 20 veteran male athletes (ATH, >5 exercise h/wk for >20 yr, 63 +/- 6 yr), we measured brachial artery endothelial function with flow-mediated dilation (FMD) before and after I/R. We induced I/R by 20 min of ischemia followed by 20 min of reperfusion. Randomized over 2 days, participants underwent either 35-min rest or IPC (3 cycles of 5-min cuff inflation to 220 mmHg with 5 min of rest) before I/R. In SED, FMD decreased after I/R [median (interquartile range)]: [3.0% (2.0-4.7) to 2.1% (1.5-3.9), P = 0.046] and IPC did not prevent this decline [4.1% (2.6-5.2) to 2.8% (2.2-3.6), P = 0.012]. In ATH, FMD was preserved after I/R [3.0% (1.7-5.4) to 3.0% (1.9-4.1), P = 0.82] and when IPC preceded I/R [3.2% (1.9-4.2) to 2.8% (1.4-4.6), P = 0.18]. These findings indicate that lifelong exercise training is associated with increased tolerance against endothelial I/R. These protective, preconditioning effects of lifelong exercise against endothelial I/R may contribute to the cardioprotective effects of exercise training.

The COVID-19 lockdown has been associated with physical inactivity. We prospectively evaluated changes in moderate-to-vigorous physical activity (MVPA) and sedentary time (ST) among 1565 cardiovascular disease (CVD) patients using validated questionnaires at 5 weeks after lockdown initiation (i.e., baseline, April 2020) and at every 4 subsequent weeks, until July 2020. Multivariate mixed model analyses were performed to identify whether age, sex, CVD-subtype, lockdown adherence and mental health factors impacted changes in physical (in)activity. Patients were 67 (interquartile range: 60–73) years and primarily diagnosed with coronary artery disease. Time spent in MVPA was 143 min/day (95% confidence interval (CI) 137, 148) at baseline. Female sex, heart-failure, fear of COVID-19 infection and limited possibilities for physical activity were independently associated with lower levels of MVPA across time. After adjusting for confounders, overall MVPA did not change. ST was 567 (95% CI 555, 578) min/day at baseline. Lack of social contact, limited possibilities for physical activity and younger age were independently associated with higher levels of ST. After adjusting for confounders, ST progressively increased following 8 (Δ+19.7 (95% CI 0.4, 39.0)) and 12 weeks (Δ+25.2 (95% CI 5.4, 47.1) min/day) of lockdown. Despite a phased relaxation of the lockdown, CVD patients progressively increased ST and reported no change in MVPA. This highlights the need to target physical inactivity during and beyond the COVID-19 pandemic.

Background Sedentary behaviour might be a potential risk factor for cognitive decline. However, the short-term effects of sedentary behaviour on (cerebro) vascular and cognitive performance in older people are unknown. Methods We used a cross-over design with 22 older adults (78 years, 9 females) to assess the short-term hemodynamic and cognitive effects of three hours uninterrupted sitting and explored if these effects can be counteracted with regular (every 30 min) two-minute walking breaks. In addition, we investigated if low versus high mental activity during the three hours of sitting modified these effects. Before and after each condition, alertness, executive functioning, and working memory were assessed with the Test of Attentional Performance battery. Additionally, cerebral blood flow velocity (Transcranial Doppler) and blood pressure (Finapres) were measured in rest, and during sit-to-stand and CO2 challenges to assess baroreflex sensitivity, cerebral autoregulation, and cerebral vasomotor reactivity. Results No short-term differences were observed in cognitive performance, cerebral blood flow velocity, baroreflex sensitivity, cerebral autoregulation, or cerebral vasomotor reactivity across time, or between conditions. Blood pressure and cerebrovascular resistance increased over time (8.6 mmHg (5.0;12.1), p p = 0.04). However, these effects were not mitigated by mental activity or by short walking breaks to interrupt sitting. Conclusions In older individuals, three hours of sitting did not influence cognitive performance or cerebral perfusion. However, the sitting period increased blood pressure and cerebrovascular resistance, which are known to negatively impact brain health in the long-term. Importantly, we found that these effects in older individuals cannot be mitigated by higher mental activity and/or regular walking breaks. Trial registration Clinical trial registration URL: https://www.toetsingonline.nl/. Unique identifier: NL64309.091.17. Date of registration: 06–02–2018.

Aerobic exercise training reduces cardiovascular morbidity and mortality in humans. In subjects with hypertension, aerobic exercise decreases blood pressure, an effect primarily mediated by changes in peripheral vascular resistance and modification in the function and structure of macro- and micro-vessels. Aerobic exercise training also has direct anti-atherogenic impacts on artery health which decrease the risk for cardiovascular events through pathways additional to direct impacts on blood pressure. The main aim of this chapter is to summarise the effect of aerobic exercise on structural and functional characteristics of conduit and resistance arteries in humans. We provide an overview of the techniques to that are used to assess vascular structure and function followed by influence of aerobic exercise training on vascular structure and function. Potential mechanisms that contribute to vascular adaptations to aerobic exercise are then discussed. Finally, we integrate the available knowledge in this area to provide evidence-based guidelines for influence of exercise training on vascular health among individuals with hypertension.

Contains fulltext : 238781.pdf (Publisher’s version ) (Open Access) Due to its cardiovascular effects sedentary behaviour might impact cerebrovascular function in the long term, affecting cerebrovascular regulatory mechanisms and perfusion levels. Consequently this could underly potential structural brain abnormalities associated with cognitive decline. We therefore assessed the association between sedentary behaviour and brain measures of cerebrovascular perfusion and structural abnormalities in community-dwelling older adults. Using accelerometery (GENEActiv) data from The Irish Longitudinal Study on Ageing (TILDA) we categorised individuals by low- and high-sedentary behaviour (≤8 vs >8 hours/day). We examined prefrontal haemoglobin oxygenation levels using Near-Infrared Spectroscopy during rest and after an orthostatic challenge in 718 individuals (66 ± 8 years, 52% female). Global grey matter cerebral blood flow, total grey and white matter volume, total and subfield hippocampal volumes, cortical thickness, and white matter hyperintensities were measured using arterial spin labelling, T1, and FLAIR MRI in 86 individuals (72 ± 6 years, 55% female). While no differences in prefrontal or global cerebral hemodynamics were found between groups, high-sedentary individuals showed lower hippocampal volumes and increased white matter hyperintensities compared to their low-sedentary counterparts. Since these structural cerebral abnormalities are associated with cognitive decline and Alzheimer's disease, future work exploring the causal pathways underlying these differences is needed.