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International audience; The rise in oxygen consumption during the transition from rest to exercise is faster in those who are endurance-trained than those who have sedentary lifestyles, partly due to a more efficient cardiac response. However, data regarding this acute cardiac response in trained individuals are limited to heart rate (HR), stroke volume and cardiac output. Considering this, we compared cardiac kinetics, including left ventricular (LV) strains and twist/untwist mechanics, between endurance-trained cyclists and their sedentary counterparts. Twenty young, male, trained cyclists and 23 untrained participants aged 18-25 years performed five similar constant workload exercises on a cyclo-ergometer (target HR: 130 bpm). During each session, LV myocardial diastolic and systolic linear strains, as well as torsional mechanics, were assessed using speckle-tracking echocardiography. Cardiac function was evaluated every 15s during the first minute and every 30s thereafter, until 240s. Stroke volume increased during the first 30-45s in both groups, but to a significantly greater extent in trained cyclists (31% vs 24%). Systolic parameters were similar in both groups. Transmitral peak filling velocity and peak filling rate responded faster to exercise and with greater amplitude in trained cyclists. Left ventricular filling pressure was lower in the former, while LV relaxation was greater, but only at the base of the left ventricle. Basal rotation and peak untwisting rate responded faster and to a greater extent in the cyclists. This study provides new mechanical insights into the key role of LV untwisting in the more efficient acute cardiac response of endurance-trained athletes at onset of exercise.

International audience; Background: Left ventricular (LV) remodeling, characterized by increased LV hypertrophy and depressed function, is observed in strength-trained athletes who use anabolic-androgenic steroids (AAS). Previous studies reported an increase in cardiac fibrosis in these athletes, which could promote intraventricular dyssynchrony. In this context, this study evaluated LV dyssynchrony in strength-trained athletes using AA; hypothesizing that the use of AAS leads to an increase in LV dyssynchrony with an increase in post-systolic shortening.Methods: Forty-four participants (aged 20-40 years) were divided into three age-matched groups: strength-trained athletes using AAS (users, n=14) and those who were not (non-users, n=15), and healthy sedentary men (controls, n=15),. After completing a survey, each participant was assessed with 2D-strain echocardiography. Left ventricular dyssynchrony was quantified using the standard deviation of the time to peak for longitudinal strains (SD), the longitudinal strain delay index (LSDI) and the segmental post-systolic index (PSI).Results: Users exhibited a greater LV mass index and higher systolic and diastolic functions than both controls and non-users. The decrease in LV strains in users was predominantly observed at the interventricular segments. The SD, LSDI and PSI, calculated on the basal inferoseptal, basal anteroseptal and basal inferolateral segments, were higher in users.Conclusion: The results strongly support that the specific LV remodeling observed in young AAS users was associated with an increase in LV dyssynchrony. The correlations with ejection fraction suggested that wasted energy, due to post-systolic shortenings, contributed in part to the decrease in LV function in strength-trained athletes using AAS.

International audience; Purpose To evaluate the effectiveness of vitamin D-3 supplementation, in secondary prevention, on cardiac remodeling and function, as well as lipid profile, in a mouse model of diet-induced type 2 diabetes. Methods Mice were fed a high fat and sucrose diet for 10 weeks. Afterward, diet was maintained for 15 more weeks and two groups were formed, with and without cholecalciferol supplementation. A control group was fed with normal chow. Glucose homeostasis and cardiac function were assessed at baseline and at the 10th and 24th weeks. Animals were killed at the 10th and 25th weeks for plasma and cardiac sample analysis. Cardiac lipid profile was characterized by LC-MS/MS. Results After 10 weeks of diet, mice exhibited pre-diabetes, mild left ventricle hypertrophy, and impaired longitudinal strain, but preserved myocardial circumferential as well as global diastolic and systolic cardiac function. After 15 more weeks of diet, animals presented with well-established type 2 diabetes, pathological cardiac hypertrophy, and impaired regional myocardial function. Cholecalciferol supplementation had no effect on glucose homeostasis but improved cardiac remodeling and regional myocardial function. After 25 weeks, non-supplemented mice exhibited increased myocardial levels of ceramides and diacylglycerol, both of which were normalized by vitamin D-3 supplementation. Conclusion This work brought to light the beneficial effects of cholecalciferol supplementation, in secondary prevention, on cardiac remodeling and function in a mouse model of diet-induced type 2 diabetes. Those cardioprotective effects may be, at least in part, attributed to the modulation of myocardial levels of lipotoxic species by vitamin D.

International audience; Purpose Physical exercise (PE) combined with nutritional approaches has beneficial effects that are widely advocated to improve metabolic health. Here we used voluntary PE together with vitamin D (VD) supplementation, which has already shown beneficial effects in primary and tertiary prevention in obese mice models, to study their combined additive effects on body weight management, glucose homeostasis, metabolic inflammation, and liver steatosis as key markers of metabolic health. Methods Ten-week-old male C57BL/6J mice were fed a high-fat/sucrose (HFS) diet for 10 wk, then assigned to a 15-wk intervention period with PE, VD supplementation, or both PE and VD supplementation. Morphological, histological, and molecular phenotype data were characterized. Results The HFS-induced increases in body mass, adiposity, and adipocyte hypertrophy were improved by PE but not by VD supplementation. The HFS-induced inflammation (highlighted by chemokines mRNA levels) in inguinal adipose tissue was decreased by PE and/or VD supplementation. Furthermore, the intervention combining PE and VD showed additive effects on restoring insulin sensitivity and improving hepatic steatosis, as demonstrated through a normalization of size and number of hepatic lipid droplets and triglyceride content and a significant molecular-level decrease in the expression of genes coding for key enzymes in hepatic de novo lipogenesis. Conclusions Taken together, our data show beneficial effects of combining PE and VD supplementation on obesity-associated comorbidities such as insulin resistance and hepatic disease in mice. This combined exercise-nutritional support strategy could prove valuable in obesity management programs.

Objectives: This study was performed to evaluate the long-term maintenance of nutritional changes promoted during an intensive initial intervention to induce body weight loss. The ability of these changes to predict long-term health outcomes was also examined. Methods: Nutritional variables, body composition, and metabolic markers collected in the RESOLVE project were analyzed before and after a 3-week intensive diet&ndash, exercise intervention (Phase 1), and during a subsequent supervision under free living conditions, of 12 months (Phase 2). Results: As expected, the macronutrient composition of the diet was modified to promote a negative energy balance during Phase 1. The decrease in carbohydrates imposed during this phase was maintained during Phase 2 whereas the increase in protein intake returned to baseline values at the end of the program. Dietary fiber intake was almost doubled during Phase 1 and remained significantly greater than baseline values throughout Phase 2. Moreover, fiber intake was the only nutritional variable that systematically and significantly predicted variations of health outcomes in the study. Conclusion: The adequacy of dietary fiber intake should be a matter of primary consideration in diet-based weight reduction programs.

International audience; The beneficial effect of vitamin D (VD) supplementation on body weight gain limitation and inflammation has been highlighted in primary prevention mice models, but the long-term effect of VD supplementation in tertiary prevention has never been reported in obesity models. The curative effect of VD supplementation on obesity and associated disorders was evaluated in high-fat- and high-sucrose (HFS)-fed mice. Morphological, histological, and molecular phenotype were characterized. The increased body mass and adiposity caused by HFS diet as well as fat cell hypertrophy and glucose homeostasis were not improved by VD supplementation. However, VD supplementation led to a decrease of HFS-induced inflammation in inguinal adipose tissue, characterized by a decreased expression of chemokine mRNA levels. Moreover, a protective effect of VD on HFS-induced hepatic steatosis was highlighted by a decrease of lipid droplets and a reduction of triglyceride accumulation in the liver. This result was associated with a significant decrease of gene expression coding for key enzymes involved in hepatic de novo lipogenesis and fatty acid oxidation. Altogether, our results show that VD supplementation could be of interest to blunt the adipose tissue inflammation and hepatic steatosis and could represent an interesting nutritional strategy to fight obesity-associated comorbidities.

IntroductionStress and obesity are two public health issues. The relationship between obesity and stress is biological through the actions of stress on the major hormones that regulate appetite (leptin and ghrelin). Many spa resorts in France specialise in the treatment of obesity, but no thermal spa currently proposes a specific programme to manage stress in obesity. The ObesiStress protocol has been designed to offer a new residential stress management programme. This thermal spa treatment of obesity implements stress management strategies as suggested by international recommendations.Methods and analysis140 overweight or obese participants with a Body Mass Index of >25 kg/m2 and aged over 18 years will be recruited. Participants will be randomised into two groups: a control group of usual practice (restrictive diet, physical activity and thermal spa treatment) and an intervention group with stress management in addition to the usual practice. In the present protocol, parameters will be measured on five occasions (at inclusion, at the beginning of the spa (day 0), at the end of the spa (day 21), and at 6 and 12 months). The study will assess the participants’ heart rate variability, cardiac remodelling and function, electrodermal activity, blood markers, anthropometric profile, body composition, psychology and quality of life via the use of questionnaires and bone parameters.Ethics and disseminationThe ObesiStress protocol complies with the ethics guidelines for Clinical Research and has been approved by the ethics committee (CPP Sud-Est VI, Clermont-Ferrand - ANSM: 2016-A01774-47). This study aimed to highlight the efficacy of a 21-day thermal spa residential programme of stress management in obesity through objective measurements of well-being and cardiovascular morbidity. Results will be disseminated during several research conferences and articles published in peer-reviewed journals.Trial registration numberNCT03578757.

PURPOSE At the onset of physical exercise, oxygen (O2) transport adapts to meet the working muscle O2 demands. Cardiac output abruptly increases through the concomitant changes of HR and stroke volume (SV), which is conditioned by the left ventricular (LV) function. The purpose of this study was to investigate the contribution of many LV diastolic and systolic function parameters, including twist-untwist mechanics, to SV adaptation during the first minutes after exercise onset. METHODS Diastolic and systolic myocardial strains and twist were monitored by two-dimensional speckle-tracking echocardiography with high temporal resolution in 28 young men (mean age, 23 ± 4 yr) who performed five similar constant work-load exercises on a cycloergometer (target HR: 125 bpm). Two-dimensional cine-loops were recorded every 15 s during the first minute of exercise, and then every 30 s for the next 3 min. RESULTS During the first 60 s of exercise, SV (from 104 ± 15 mL to 126 ± 21 mL, P < 0.001) increased concomitantly with LV strain and strain rates. Early filling was the main SV determinant during this phase, probably linked to the increase of venous return (at the very beginning of exercise), LV relaxation (from 1.5 ± 0.3 s to 2.5 ± 0.4 s, P < 0.001) and untwisting (from -78 ± 34°·s to -165 ± 61°·s, P < 0.001). After the first minute, SV remained constant, whereas LV untwisting continued to increase (from -165 ± 61°·s to -187 ± 60°·s, P < 0.001) and the other systolic and diastolic parameters reached a plateau. CONCLUSIONS This study gives new mechanical insights into LV kinetics to address the challenge of SV response at the onset of exercise.

Aims: The aim of the investigation was to evaluate layer-specific right ventricular (RV) deformation in normotensive and hypertensive subjects with type 2 diabetes mellitus (DM). Methods: This cross-sectional study included 129 subjects (40 controls, 42 normotensive DM and 47 hypertensive DM patients) who underwent complete two-dimensional echocardiographic examination (2DE) including multilayer strain analysis. Results: 2DE RV global and free wall longitudinal strains were reduced in normotensive and hypertensive DM subjects than in controls. RV global longitudinal layer-specific strains (endo-, mid- and epicardial) were lower in normotensive and hypertensive DM patients than in controls. On the other side, layer-specific strains of RV free wall were lower in hypertensive DM patients than in controls, without significant difference between controls and normotensive DM subjects. Parameters of DM control (fasting glucose and glycosylated hemoglobin) were associated with 2DE RV global longitudinal endo- and mid-myocardial layer strain. Conclusions: Diabetes and hypertension significantly influence RV mechanics assessed by 2DE conventional and 2DE multilayer strain. Hypertension has an additive unfavorable influence on RV deformation in diabetic patients. Laboratory parameters of diabetic control were associated with RV structure, diastolic function and mechanics assessed with complex 2DE strain analysis.

Discrepancies are present in the literature on resting myocardial mechanics in patients with uncomplicated type 2 diabetes mellitus (T2DM). Data are noticeably sparse regarding circumferential function and torsional mechanics. Resting deformation imaging may not be sensitive enough to detect subtle dysfunctions. The aim of this study was thus to comprehensively evaluate myocardial mechanics in patients with T2DM at rest and to investigate whether dobutamine stress echocardiography could unmask functional alterations that would remain otherwise subtle at rest.Forty-four patients with T2DM and 35 healthy control subjects of similar age and sex were prospectively recruited. After conventional echocardiography, myocardial mechanics was evaluated at rest and during low-dose dobutamine stress echocardiography (target heart rate, 110 beats/min).Patients with T2DM presented with altered global diastolic function but preserved systolic function. Deformation imaging indexes were similar between groups at rest, but significant differences were noticed under dobutamine infusion for longitudinal strain (-21.2 ± 2.4% vs -24.2 ± 2.5%, P .001), circumferential strain (apex, -32.3 ± 5.3% vs -36.3 ± 5.3%, P = .002; papillary muscle, -25.6 ± 3.2% vs -28.0 ± 3.6%, P = .001; base, -23.2 ± 3.6% vs -25.3 ± 3.8%, P = .03), apical (11.2 ± 4.4° vs 14.1 ± 6.3°, P = .020) and basal (-12.2 ± 3.3° vs -14.3 ± 3.9°, P = .021) rotation, and twist (21.9 ± 5.9° vs 26.8 ± 8.3°, P = .007). Multivariate analysis identified epicardial fat, dyslipidemia, and fasting glycaemia as significant contributors to the changes from rest to dobutamine.These findings demonstrate the usefulness of dobutamine stress echocardiography in establishing impairments in myocardial mechanics in patients with uncomplicated T2DM. Systemic metabolic disturbances and epicardial fat act as the main contributors to the blunted response to dobutamine stress in these patients.

Summary Background Detailed analysis of layer-specific mechanical changes in patients with type 2 diabetes mellitus (DM) might improve insight into left ventricular (LV) remodelling and diabetic cardiomyopathy. Aim We sought to investigate layer-specific LV deformation in patients with DM, with and without hypertension. Methods This cross-sectional study included 146 subjects (44 controls; 48 patients with DM; 54 patients with DM and hypertension) who underwent complete examination by two-dimensional echocardiography (2DE), including multilayer strain analysis. Results 2DE LV longitudinal and circumferential strains deteriorated progressively and significantly from controls, through patients with DM, to patients with DM and hypertension. 2DE radial strain was lower in patients with DM and hypertension than in controls. 2DE longitudinal and circumferential mid-myocardial and epicardial layer strains decreased progressively from controls to patients with DM and hypertension, whereas endocardial layer strain was lower in patients with DM and patients with DM and hypertension than in controls. Variables of DM control (fasting glucose and glycated haemoglobin) were associated with 2DE LV longitudinal and circumferential layer-specific strains, independent of age, body mass index, blood pressure, LV diastolic function and hypertrophy in patients with DM. Conclusion DM and hypertension significantly affect LV deformation assessed by 2DE traditional strain and 2DE multilayer strain. Hypertension showed an additional negative effect on LV deformation in patients with DM. Fasting glucose and glycated haemoglobin were associated with LV mechanics evaluated by comprehensive 2DE strain analysis, independent of LV structure and diastolic function.

Olive oil vascular benefits have been attributed to hydroxytyrosol (HT). However, HT biological actions are still debated because of its high metabolisation into glucuronides (GC). The aim of this study was to test HT and GC vasculoprotective effects on aorta rings from male Wistar rats. Vasorelaxant dose-responses to acetylcholine (ACh) or sodium nitroprusside (SNP) were realized in presence/absence of tert-butylhydroperoxide (t-BHP) (30 min, 500 μM). To prove this antioxidative effect, DHE staining was realized on phenol-treated aortas in oxidative stress conditions. Implication of bilitranslocase, a phenol transporter, and β-glucuronidase, implicated in deconjugation, were assessed using phenylmethanesulfonyl fluoride (PMSF, 100 μM, 20 min) and saccharolactone (SAL, 300 μM, 60 min), respectively. In addition, β-glucuronidase protein expression was assessed by western blot after using the same experimental procedures. In presence of oxidative stress, HT and GC enhanced endothelium-dependent and -independent relaxation to ACh and SNP compared to t-BHP-treated aortas. This effect was associated with a significant reduction in DHE staining for phenol-treated aortas compared to t-BHP-treated aortas. However, this protective effect was lost for GC when a washing step was introduced between phenols incubation and t-BHP stress. Bilitranslocase inhibition with PMSF reduced significantly HT but not GC effect on the vascular function upon stress induction. Moreover, GC protective effect in oxidative stress conditions was reduced by pre-incubation of aorta rings with SAL and was not associated with a reduction in β-glucuronidase protein expression. Finally, only HT was detected by high-pressure liquid chromatography in aorta rings incubated with GC and t-BHP. These results suggest that in conditions of oxidative stress, GC has to be deconjugated into HT that is transported through the cell membrane by bilitranslocase to produce its protective effect on vascular function.

With an aging population and the increasing prevalence of heart failure with preserved ejection fraction, developing strategies to prevent diastolic dysfunction is crucial. Regular endurance training has been suggested to be one such strategy. However, the underlying mechanisms of training, including the effect on left ventricular (LV) untwist, which promotes LV filling, are unclear and studies exploring the heart during exercise in the aging heart are lacking. Cardiopulmonary exercise testing with speckle tracking echocardiography was realized in male subjects: 16 young athletes (YA), 19 young controls (YC), 22 middle-aged athletes (MA) with a lifelong history of endurance training, and 20 middle-aged controls (MC). During exercise, the early filling was lower in MC compared to YC, whereas it was preserved between YA and MA. At exercise, peak untwisting rate/peak twist ratio and the percentage of untwist during isovolumic relaxation time were decreased in senior groups but higher in YA and MA compared to age-matched controls. Early diastolic filling reserve correlated with untwisting rate/peak twist reserve in YA and MA (R 2 = 0.22, p

Controversy exists on whether endothelial function is enhanced in athletes. We sought to systematically review the literature and determine whether endothelial function, as assessed by flow-mediated dilation (FMD), is greater in athletes across all ages relative to that in their age-matched counterparts.We conducted a systematic search on MEDLINE, Cochrane, Scopus, and Web of Science since their inceptions until July 2013 for articles evaluating FMD in athletes. A meta-analysis was performed to compare the standardized mean difference (SMD) in FMD of the brachial artery between athletes and age-matched control subjects. Subgroup analyses and meta-regression were used to identify sources of heterogeneity.Twenty-one articles were included in this analysis, comprising 530 athletes (452 endurance trained, 49 strength trained, and 29 endurance and strength trained) and 376 control subjects. After data pooling, FMD was higher in athletes than that in control groups (SMD, 0.48; P = 0.008). In subgroup analyses, young athletes (40 yr) presented increased baseline brachial artery diameter (mean difference, 0.40 mm; P0.00001) and similar FMD (SMD, 0.27; P = 0.22) compared with those in controls. In contrast, master athletes (;50 yr) showed similar baseline brachial artery diameter (mean difference, 0.04 mm; P = 0.69) and increased FMD (SMD, 0.99; P = 0.0005) compared with those in controls.The current meta-analysis provides evidence that master athletes but not young athletes exhibit greater FMD compared with that in age-matched healthy controls, thus suggesting that the association between high levels of exercise training and increased FMD is age dependent.

Introduction Metabolic syndrome (MetS), a cluster of cardiovascular risk factors, increases the incidence of type 2 diabetes (DB2). And among them, obesity, defined as the expansion of white adipose tissue (AT), which stores excessive energy intake, is associated to vitamin D (vitD) deficiency. Aside, growing evidences suggest that physical activity (PA) is efficient to reduce MetS and its associated complications. Objectives The aim of the study was to assess the impact of PA associated with vitD supplementation on MetS cardiovascular risk factors. Method In this context, C57/bl6 mice (n = 110) were fed with an obesogenic high fat/high sucrose (HFS) diet during 10 weeks. Then, mice underwent PA and vitD supplemented HFS diet during 15 weeks. Mice were monitored for weight, glucose and insulin tolerance and maximum aerobic capacity up to 25 weeks of protocol, and plasma and AT were collected after sacrifice. Results PA reduced significantly weight gain (−20%), adiposity (−23%) and enhanced physical performances (+26%) compared to HFS mice. VitD supplementation associated to PA did not provide additional benefits on these parameters. Nevertheless, insulin sensitivity was significantly improved after 15 weeks of PA + vitD supplementation, with a normalization to control mice values. On the other hand, inguinal AT gene expression analysis revealed: – a reduced inflammation, with pro-inflammatory mediators MCP1 (CCL-2) and RANTES (CCL-5) decreased mRNA levels; – increased lipid oxidation metabolism with PGC1-a (Peroxisome proliferator-activated receptor gamma coactivator 1-alpha) and CPT1b (Carnitine Palmitoyltransferase-1b) increased mRNA levels after PA + vitD in comparison to inguinal AT from HFS mice. Conclusions Our study underlines that PA associated to vitD supplementation prevent DB2 development in obese mice, with a decrease of inflammation and enhanced lipid catabolism in AT. More analysis is undergoing to characterize the mechanisms involved.

Background Discrepancies are present in the literature on resting myocardial mechanics in patients with uncomplicated type 2 diabetes mellitus (T2DM). Data are noticeably sparse regarding circumferential function and torsional mechanics. Resting deformation imaging may not be sensitive enough to detect subtle dysfunctions. The aim of this study was thus to comprehensively evaluate myocardial mechanics in patients with T2DM at rest and to investigate whether dobutamine stress echocardiography could unmask functional alterations that would remain otherwise subtle at rest. Methods Forty-four patients with T2DM and 35 healthy control subjects of similar age and sex were prospectively recruited. After conventional echocardiography, myocardial mechanics was evaluated at rest and during low-dose dobutamine stress echocardiography (target heart rate, 110 beats/min). Results Patients with T2DM presented with altered global diastolic function but preserved systolic function. Deformation imaging indexes were similar between groups at rest, but significant differences were noticed under dobutamine infusion ( Table 1 ). Multivariate analysis identified epicardial fat, dyslipidemia, and fasting glycaemia as significant contributors to the changes from rest to dobutamine. Conclusion These findings demonstrate the usefulness of dobutamine stress echocardiography in establishing impairments in myocardial mechanics in patients with uncomplicated T2DM. Systemic metabolic disturbances and epicardial fat act as the main contributors to the blunted response to dobutamine stress in these patients.

AB Introduction: Prolonged and strenuous exercise (PSE) induces transient left ventricular (LV) dysfunction. Although a consensus exists regarding the decrease in diastolic function, the existence of a decrease in systolic function by a PSE remains controversial, probably due to the transient tachycardia and changes in loading conditions observed upon the completion of exercise. Therefore, the objective was to evaluate LV systolic function before and after a PSE using two-dimensional speckle tracking echocardiography not only at rest but also during incremental tests to adjust heart rates (HR). Methods and Results: Sixteen healthy young men (23 +/- 3 yr old) performed a 3-h period of intensity-controlled upright cycling. LV strain (S), systolic strain rate (SR), rotation, and systolic rotational rate were evaluated by two-dimensional speckle tracking echocardiography before and after a 3-h period of PSE at rest and during incremental tests. Posttest evaluation was performed once the HR had returned to the pretest value. Under resting conditions, parameters of systolic function were either unchanged or increased after the PSE. However, during the incremental test, all LV systolic SR and apical rotational rates were decreased after PSE (radial SR at workload 3 (W3): 2.21 +/- 0.12.s-1 vs 1.87 +/- 0.10.s-1, P < 0.01 and apical rotational rate at W3: 128 +/- 28 deg.s-1 vs 105 +/- 26 deg.s-1, P < 0.05). Regression analyses between LV systolic SR and HR showed lower y-intercepts without differences in slopes, suggesting a decrease of both global and regional systolic functions irrespective of HR after the PSE. Conclusion: Our findings based on LV S and SR data during incremental tests demonstrate that the 3-h period of PSE induces LV systolic dysfunction

Objective Recent findings indicated silent incipient myocardial dysfunction in juvenile obesity despite normal global cardiac function. The present study investigated whether lifestyle intervention is able to favorably impact these obesity-related myocardial abnormalities and whether improvements are related to changes in insulin resistance and cardiac remodeling. Design and Methods Twenty-eight severe obese adolescents (OB) participated in a 9 month lifestyle intervention program (LIP) based on aerobic exercise and diet. Twenty healthy adolescents (CG) served as controls. Conventional echocardiography and myocardial mechanics were obtained at baseline and follow-up along with insulin resistance. Results Insulin sensitivity improved (P < 0.001) and body weight decreased (P < 0.001) consecutive to LIP. At baseline, OB had depressed longitudinal (L) strain (CG: −18.3 ± 2.6, OB: −14.2 ± 3.6%, P < 0.001) and enhanced twist compared to controls. The LIP in OB restored L strain to normal values (−16.9 ± 3.5%, NS), whereas it did not affect twist mechanics. From stepwise multiple regression analysis, only baseline L strain and changes in BMI Z-score (r2-adjusted = 0.49, P < 0.001) emerged as independent predictors of L strain changes. Conclusions Juvenile obesity is associated with myocardial mechanic abnormalities that can be partly corrected by lifestyle intervention. Restoration of longitudinal myocardial function occurs in the absence of left ventricular remodeling changes and is not associated with insulin resistance improvements.

Objective The aim of the study is to characterize left ventricular (LV) myocardial mechanics in adults with metabolic syndrome (MetS), and elucidate the effects of multiple risk-factors on myocardial function using speckle tracking echocardiography (STE); a more sensitive method than conventional echocardiography for detecting subclinical myocardial dysfunction. Design and Methods Cross-sectional analyses of 92 adults (50–70 years) with MetS, and 50 healthy controls included conventional echocardiography, blood biochemistry, and STE-derived myocardial longitudinal, circumferential, and twist mechanics. Results Using conventional measures, MetS participants revealed LV hypertrophy and reduced diastolic function compared with controls, while systolic function was preserved. From STE, MetS participants showed attenuated longitudinal strain (−16.8% ± 2.8% vs. −20.6% ± 2.7%), and both diastolic (1.1 ± 0.2 vs. 1.4 ± 0.3 s s−1) and systolic (−1.0 ± 0.1 vs. −1.2 ± 0.2 s s−1) strain rate (SR). Circumferential strain, SR, and twist mechanics did not differ. Participants with the highest number of MetS factors or diabetes demonstrated the greatest reduction in longitudinal strain and SR. Abdominal obesity, TNF-α, HbA1c, and systolic dyssynchrony explained 48% of impairment in longitudinal strain. Conclusions Impaired longitudinal myocardial diastolic and systolic function, but preserved circumferential function and twist mechanics were found in MetS participants, indicative of altered subendocardial function. This dysfunction was best predicted by abdominal obesity, inflammation, glucose-intolerance, and systolic dyssynchrony.

Aims: The purpose of our study was to determine the effect of lifestyle intervention on left ventricular (LV) regional myocardial function in patients with metabolic syndrome (MetS) and investigate the relationships of the changes in myocardial function to changes in epicardial adipose tissue (EAT), inflammatory profile and MetS components. Methods: Eighty-seven MetS patients were enrolled in a 6 month lifestyle intervention program based on dietary management and increased physical activity, and compared with 44 aged and sex-matched healthy controls. MetS individuals were allocated to different groups randomized (computer-generated randomization) on exercise modalities (high-intensity dominant resistance or aerobic training, and moderate-intensity of both modes). EAT was measured by transthoracic echocardiography and LV longitudinal strains and strain rates were obtained using vector velocity imaging. Blood chemistry allowed assessments of adipocytokines (TNF-α: tumor necrosis factor α, PAI active: active plasminogen activator inhibitor-1 and adiponectin) and glucose tolerance markers. Results: Regardless of exercise training modalities, lifestyle intervention improved significantly LV strains and strain rates (p < 0.001) as well as metabolic and inflammatory profiles. Stepwise multiple regression analyses revealed EAT (β = 0.73, p < 0.01), log adiponectin (β = − 0.13, p < 0.05) and log TNF-α (β = 0.15, p < 0.05) as independent predictors of LV longitudinal strain (R2 = 0.74, p < 0.001) while myocardial function improvement consecutive to lifestyle intervention was explained by EAT changes only (R2 = 0.54, p < 0.001). Conclusion: The mechanisms through which regional myocardial function is impaired in MetS and improved consecutive to intervention involved EAT, possibly via paracrine effects of adipocytokines. EAT should be considered as a future therapeutic target of interest in the treatment of metabolic-related cardiac diseases.

Hydroxytyrosol (HT) is known to be a strong polyphenolic antioxidant of olive oil. However, its in vivo effects are controversial since intestinal absorption is low and it is highly metabolized into glucuronides (GC), suggesting that these metabolites could be responsible of HT biological activity in vivo . Our objectives were to study the direct effects of HT and its glucuronides on vascular function and the oxidative stress vascular protection on healthy and diabetic rats The vascular function was assessed on aortas from diabetic-High Fat Sucrose diet (HFS) and age-matched (22 weeks) control fed with a standard diet (SD) Wistar rats, in comparison to young (9 weeks) control Wistar rats (ySD). The endothelium-dependent and independent vasorelaxing effects of these compounds were assessed via incremental doses of HT and GC (10 -9 to 10 -4 M) and compared to Resveratrol (Res). Expression and phosphorylation of Ser 1177 eNOS were measured by Western blot. To evaluate the anti-oxidative effects of these polyphenols (100 μM, 5min), vascular function was assessed in presence/absence of t -BOOH (500μM, 30min). HT and GC did not show any endothelium-dependent and independent vasorelaxation effects in ySD and HFS rats while Res produced vasorelaxing effect at 10 -4 M in all groups of rats and no vasorelaxant effects were noticed in SD rats. The overall absence of vasorelaxing effect can be explained by the lack eNOS phosphorylation. As for the antioxidative properties, HT, GC and Res increased significantly endothelium-dependent relaxation in comparison of aorta rings treated only with t -BOOH (79.9%±9.2, 74.1%±8.6, 71.0%±8.2, 48.4%±5.3 respectively). In addition, co-incubation of HT/GC and Res/GC increased even more the vasorelaxation under pro-oxydant conditions. In diabetic HFS rats, (i) the incubation for 5min with HT and GC did not improve neither vasorelaxation nor the contraction; (ii) however, a prolonged 30 min incubation resulted in more pronounced and significant contractile (64.8%±12.4 and 95.6%±16.3, respectively) and endothelium-dependent relaxation effects (30%±7.5 and 58.1%±10.3 respectively) for GC in comparison to HT. In conclusion, GC seems to be responsible for the anti-oxidative properties of olive oil but further experimentations have to be realized concerning its possible interconversion in HT by β-glucuronidase. The author hereby declares no conflict of interest

Background— Abnormal left ventricular (LV) deformational mechanics have been demonstrated in patients with hypertrophic cardiomyopathy (HCM) at rest, but there is a lack of information on their adaptation to exercise. The aim of this study was to assess the adaptability of LV strains and torsional mechanics during exercise in HCM patients. Methods and Results— Twenty nonobstructive HCM patients (age, 48.3±12.3 years; 14 men) and 20 control subjects underwent speckle-tracking echocardiographic measurement of longitudinal, radial, and circumferential strains, systolic twist, and diastolic untwisting rate (UTR) at rest and submaximal exercise. HCM patients showed lower resting longitudinal (−15.7±5.0% versus −19.4±2.6%, P P P P P P P =0.68). Conclusions— HCM patients had severely limited strain adaptability and no LV twisting reserve at exercise. They had reduced and delayed UTR with reduced systolic-diastolic coupling efficiency by twist-untwist mechanics.

International audience; Objective: Although increased blood flow (BF) in exercising muscles is thought to be impaired in obese subjects and may contribute to physical inactivity, data are scarce in this regard and the involvement of endothelium dysfunction remains partly hypothetical. Methods: A total of 16 middle-aged obese men (body mass index, BMIX30 kg m À2) and 16 normal-weight men (BMIo25 kg m À2), matched for age, were recruited. We used ultrasonography to compare intima-media thickness (IMT) and distensibility of the carotid artery, flow-mediated dilation (FMD), nitrate-dependent dilation (NDD) and peak BF during post-ischemic hyperemia in the brachial artery (a conduit artery), and leg BF during knee-extensor exercise (indicative of resistance vessel function) in obese and in normal-weight men. In addition, 10 obese men participated in an 8 week individualized low-intensity training program. Results: Compared with normal-weight men, obese men had higher carotid IMT (0.50 ± 0.01 vs 0.62 ± 0.04 mm, Po0.05) but lower carotid distensibility (0.26±0.03 vs 0.11±0.03 mm Hg À1 10 À2 , Po0.05), FMD (5.7±0.4 vs 3.3±0.5%, Po0.05) and peak BF during post-ischemic hyperemia (398 ± 52 vs 229 ± 24%, Po0.05), despite similar maximal shear rate, without NDD differences. Lower limb BF (ml min À1 100 g À1) increased significantly from rest to maximal exercise in both groups with lower values in obese men (at peak power, 36.9 ± 1.6 vs 31.5 þ 2.2 ml min À1 100 g À1 , Po0.05). Exercise training normalized carotid distensibility (0.14±0.04 before vs 0.23±0.03 mm Hg À1 10 À2 after training, P ¼ 0.09) and FMD (2.7±0.4 before vs 4.8±0.5% after training, Po0.05), but did not improve brachial post-ischemic peak BF or exercising leg BF. Conclusions: In obese men, conduit and resistance vessel reactivity is depressed, but a short-term low-intensity exercise training improves distensibility and endothelium dependent vasodilation in the large conduit artery, but not post ischemic or exercise muscle BF.

The contraction of cardiomyocytes induces a systolic increase in left ventricular (LV) normal (radial, circumferential and longitudinal) and shear strains, whose functional consequences have not been evaluated, so far, in athletes. We used 2D ultrasound speckle tracking imaging (STI) to evaluate LV regional strain in high-level cyclists compared to sedentary controls. Sixteen male elite cyclists and 23 sedentary controls underwent conventional, tissue Doppler, and STI echocardiography at rest. We assessed LV long and short axis normal strains and shear strains. We evaluated circumferential–longitudinal shear strain from LV torsion, and circumferential–radial shear strain from the difference between subendocardial and subepicardial torsion. Apical radial strain (42.7 ± 10.5%versus 52.2 ± 14.3%, P < 0.05) and LV torsion (6.0 ± 1.8 deg versus 9.2 ± 3.2 deg, P < 0.01) were lower in cyclists than in controls, respectively. Rotations and torsion were higher in the subendocardial than in the subepicardial region in sedentary controls, but not in cyclists. Haemodynamic and tissue Doppler based indexes of global LV diastolic and systolic functions were not different between cyclists and controls. Athlete's heart is associated with specific LV adaptation including lower apical strain and lower myocardial shear strains, with no change in global LV diastolic and systolic function. These mechanical alterations could improve the cardiovascular adjustments to exercise by increasing the radial strain and torsional (and thus untwisting) response to exercise, a key element of diastolic filling and thus of cardiac performance in athletes.

Although cardiotoxic effects of highly active antiretroviral therapy (HAART) are a growing concern, there is a lack of prospective studies of subclinical involvement of the heart in human immunodeficiency virus (HIV)-infected patients. This study evaluated noninvasively cardiac morphologic characteristics and function in HIV-positive (HIV(+)) men receiving HAART for > or =2 years with no clinical evidence of cardiovascular disease. Echocardiography at rest, including tissue Doppler imaging and exercise testing, were performed in 30 HIV(+) men (age 42.1 +/- 4.7 years, duration of HIV infection 10.4 +/- 4.7 years, duration of HAART 5.3 +/- 2.1 years) and 26 age-matched healthy controls. At rest, HIV(+) patients had similar left ventricular (LV) mass indexed to height(2.7) (40.6 +/- 9.5 vs 37.5 +/- 9.3 g/m; p >0.05), but a higher prevalence of LV diastolic dysfunction (abnormal relaxation or pseudonormal filling pattern in 64% of patients vs 12% of controls; p

International audience; Hypoxia-induced pulmonary hypertension is associated with an impairment of nitric oxide-mediated vasorelaxation in the pulmonary circulation that is not prevented by exercise training. The present study was designed to test the hypothesis that a decrease in l-arginine bioavailability could be involved in this blunted response to exercise training. Male Wistar rats were randomly assigned to 4 groups: normotensive sedentary, normotensive trained, pulmonary hypertensive sedentary, pulmonary hypertensive trained. Pulmonary hypertension was induced by chronic exposure to hypobaric hypoxia (PIO(2) approximately 90 mmHg). Endothelium-dependent vasorelaxation to acetylcholine (10(-8)-10(-4) M) with or without l-arginine (10(-3) M) and/or nitro-l-arginine methyl ester (5.10(-6) M) was assessed on isolated pulmonary arterial rings. Maximal relaxation to acetylcholine was impaired in both pulmonary hypertensive groups. Acute l-arginine supplementation improved acetylcholine-induced vasorelaxation in the pulmonary hypertensive trained rats (P

Aim Specific cardiac adaptations leading to lack of improvement in left ventricular (LV) filling have been recently established consecutive to altitude training (AT). The aim of this study was to investigate the contribution of LV relaxation properties, preload and dimensions in the explanation of this hypoxia (with or without training)-induced absence of LV filling enhancement. Methods Male rats were randomly assigned to four groups: Normoxic groups (PIO2 = 159 mmHg) with (NT) or without (N) training, and hypoxic groups (PIO2 = 110 mmHg) with (CHT) or without training (CH). Cardiac adaptations were evaluated by Doppler-echocardiograhy, cardiac weighing, aortic pulsed-Doppler transducer and intraventricular pressure variations. Results Our major finding was that the lack of LV filling improvement consecutive to AT was not accounted for by deleterious effects of hypoxia exposure on LV relaxation properties but rather explained by altitude-induced cardiac morphological and preload alterations.

The present study was conducted to investigate both skeletal and somatic developments in a group of highly trained prepubertal girl gymnasts at the beginning of their peak bone mass acquisition. The experimental group included 14 gymnasts who had trained 12—15 h per wk for 3 y before starting the study. The control group consisted of 15 non-exerciser children and 6 swimmers training for 5—6 h/wk. Body composition and bone mineral density (BMD) of the total body, lumbar spine, non-dominant hip and radius were measured using dual-energy X-ray absorptiometry. Calculation of bone age and measurement of body height and weight were done. All measurements and analyses were carried out twice with a 1-y interval by the same technician. There were no differences between groups in age, bone age, body height and weight and lean tissue mass at the start of the study and 1 y later. The somatic changes observed between the first and second years tended to be greater in gymnasts compared to controls, except for body height. At the first and second investigations, BMD values in the gymnasts were statistically higher than in the controls at all skeletal sites, but not for the whole body (from p < 0.05 to p < 0.001, depending on the site). Percentage changes in BMD pre-investigation compared with post-investigation tended to be greater in gymnasts. Variations in lean mass, bone age and fat mass were found to be the best independent predictors of annual changes in BMD for total body, lumbar spine, trochanter and femoral neck sites. These results suggested that high-volume impact loading training could promote a higher annual gain in bone mineral acquisition at the strained body sites in prepubertal girls without affecting somatic growth dimensions. □Bone mass, growth, gymnasts, prepubertal training, somatic development

UNLABELLED The aim of this study was to examine the effect of two endurance training regimens of varying duration and frequency on maximal oxygen uptake (VO2max) of prepubertal boys and girls. The subjects consisted of 84 prepubertal children, aged 10-11 y. Two groups, EG1 (n = 36) and EG2 (n = 20), were involved in a 13 wk endurance training programme (intensity: higher than 80% of maximal heart rate for both groups; frequency: 3 and 2 sessions per week: duration: 25-35 min and 15-20 min per session in the target zone, for EG1 and EG2, respectively). Another group of 28 children served as a control group. Each subject performed a continuous and progressive exercise test to exhaustion on a cycle ergometer to evaluate VO2max before and after the 13 wk study period. The main findings of this study were: (i) there was no improvement in VO2max after a training programme with the following characteristics: 2 sessions per week with 15-20 min of exercise performed at an intensity higher than 80% of maximal heart rate; (ii) a VO2max enhancement (on average +7%) was seen only in children who participated in a training programme organized on the basis of three sessions per week during which exercise intensities higher than 80% of maximal heart rate were sustained for at least 25 min per session; and (iii) there was no gender difference in the training response. CONCLUSION It appeared from this longitudinal study that only a programme with continuous activity, organized on the basis of three sessions per week, with 25-35 min at an intensity higher than 80% of maximal heart rate at each session, enhanced VO2max in prepubertal boys and girls.

The aim of the present study was to investigate the gender effect of an endurance training programme on the maximal oxygen uptake (VO2max) of prepubertal children. The subjects comprised eighty-five 10-11-y-old prepubertal children: 35 (17 girls, 18 boys; EG) were involved in a 13-wk running training programme and 50 (22 girls, 28 boys; CG) served as a control group. Each subject carried out a continuous and progressive cycle ergometer test before and after the 13-wk study period under the same conditions and procedures. Oxygen consumption, carbon dioxide, ventilation and heart rate (HR) were continuously monitored during the test. The training programme consisted of interval and continuous long-distance running (frequency: 3 times a week, duration: 1 h per session, intensity: higher than 80% of maximal HR). V02max significantly increased after the training programme for EG (before = 42.3 +/- 7.7, after = 45.3 +/- 7.5 ml x min(-1) x kg(-1), p < 0.01), while no alterations were noticed for CG (before = 43.1 +/- 6.7, after = 42.6 +/- 7.6 ml x min(-1) x kg(-1), p < 0.01). Such an increase was higher in the girls (+9.1%) than the boys (+4.6%). The lower initial fitness of the girls could explain this, however, because a significant relationship was found between the percentage of VO2max increase after training and the initial VO2max. The present longitudinal study shows that maximal oxygen uptake can increase in prepubertal children after an aerobic training programme and that such an increase is of the same order in boys and girls when the initial aerobic fitness is taken into account.

BackgroundYoung women are under-represented in cardiovascular disease research, with obesity and cardiometabolic risk factor interventions generally targeting older adults. Furthermore, appropriate study designs for young women remain uncertain. This study aimed to assess the impact of a 12 week multi-disciplinary lifestyle intervention on cardiometabolic risk factors in premenopausal women with abdominal obesity.MethodsWomen aged 18-30 y with abdominal obesity [waist circumference (WC) ≥ 80 cm] were randomised to a 12 week lifestyle intervention (n = 26) of physical activity, nutrition education and cognitive behavioural therapy, or a wait-list control group (n = 17). Both groups completed anthropometric, biochemical, nutrition and fitness testing, at pre (0 weeks) and post (12 weeks), with intervention participants completed follow-up testing at 24 weeks.ResultsResults from a linear mixed model showed no between-group differences, other than increased physical activity in the intervention group, at post. In the intervention group alone, positive within-group changes were observed in WC, waist-hip-ratio (WHR), waist-height-ratio (WHtR), resting heart rate, blood pressure, predicted VO2max, and total energy intake. Most changes were maintained at 24 weeks post-intervention. Similar within-group improvements were observed in control participants in WC, WHR, WHtR, and systolic blood pressure but no changes were detected in physical activity and nutrition.ConclusionsCardiometabolic risk factors were decreased as a result of a lifestyle intervention in young women with abdominal obesity. It is difficult to describe observations in the control group without greater understanding of the behaviour of wait-list participants.Trial registrationAustralian New Zealand Clinical Trials Registry ACTRN12612001017819.

Abdominal obesity is an independent risk factor for cardiovascular disease. The effect of abdominal obesity on myocardial function in young obese women remains unknown. Therefore, we aimed to investigate cardiac morphology and function, myocardial deformation, and mechanical indices, in young women with and without abdominal obesity.Cross-sectional analyses of 39 women with abdominal obesity (waist circumference ≥ 80 cm) and 33 nonobese control subjects (waist circumference80 cm) aged 18-30 years underwent conventional echocardiographic measures of cardiac morphology and function together with tissue Doppler, and 2-dimensional speckle tracking measures of myocardial deformation and mechanics. Cardiometabolic risk factors including anthropometric, hypertension, biochemistry, and fitness were also assessed.Standard echocardiography results for cardiac morphology and function were similar between groups, with the exception of larger left atrial dimensions in women with abdominal obesity (P ≤ 0.05). Compared with control subjects, women with abdominal obesity also demonstrated reduced systolic and diastolic mitral annular plane velocities, increased left atrial pressure surrogates (E/diastolic mitral annular plane velocity), and prolonged timing measures of diastolic function including isovolumic relaxation time and transmitral deceleration time (P ≤ 0.05). In addition, longitudinal strain and diastolic strain rate were reduced in women with abdominal obesity (P ≤ 0.05) but circumferential deformation and myocardial mechanics (twist indices and rotation) were preserved. Markers of abdominal obesity retained an independent direct correlation with parameters of cardiac dysfunction, explaining 12%-39% of the overall variability.A young, otherwise healthy group of women with abdominal obesity displayed subclinical cardiac dysfunction indicated using selected tissue Doppler imaging and speckle tracking echocardiography measures.

The effects of anabolic androgenic steroids (AASs) on left ventricular (LV) diastolic function in strength-trained athletes are controversial. The main objective of this study was to evaluate the effects of regular AAS administration in bodybuilders using pulsed tissue Doppler imaging (TDI) to evaluate LV relaxation properties. Fifteen male bodybuilders with a history of intensive, long-term strength training and 16 age-matched sedentary controls were recruited. Six of the bodybuilders reported regular use of AASs, and 9 were drug free. To assess LV diastolic function, each subject underwent standard Doppler echocardiography and pulsed TDI. Drug-using bodybuilders exhibited altered LV diastolic filling characterized by a smaller contribution of passive filling to LV filling compared with their drug-free counterparts. TDI measurements indicated that drug-using bodybuilders had smaller peak E(m) than drug-free bodybuilders and sedentary controls, except at the level of the anterior wall, at which peak E(m) was significantly smaller than in drug-free bodybuilders only. The E/E(m) ratio, an index of LV filling pressures, was not affected by strength training or by AAS use. Drug-using bodybuilders exhibited larger LV end-diastolic diameters, volumes, and masses than their drug-free counterparts. However, no difference was found in LV wall thickness between the groups. In conclusion, drug-using bodybuilders showed a decrease in the contribution in LV passive filling to LV filling associated with a decrease in LV relaxation properties. Because no wall thickening was obtained in drug-using bodybuilders, the decrease in LV relaxation properties might have been be due to an alteration in the active properties of the myocardium, but that has yet to be confirmed.

Background In children, there is very limited evidence focusing on the beneficial effect of exercise training on heart rate variability (HRV) during childhood. Despite the fact that more and more children are engaged in intensive training programs, the question arises if such intensive training involves deleterious effects on the cardiac autonomic nervous system during childhood. Thus the aim of the present study was to compare HRV parameters in highly trained swimmer boys and untrained counterparts. Methods Twenty prepubertal boys, aged 11–12 years old, took part in the study. The children were divided into 11 highly trained prepubertal swimmers (training sessions of 8–10 h weekly for at least 4 years) and 9 age-matched active boys. HRV analysis was performed on diurnal recordings in the frequency (short-term recordings 6 min the most ‘vagal’) and time (long-term recordings 4 h centred on the 6 min most ‘vagal’) domains. Results No significant differences were obtained between groups for all frequency variables whatever the mode of expression (absolute in ms2, relative in Ln or %). All time-domain components were not significantly different in swimmers and untrained boys. Conclusions The results of the present study demonstrate that participating intensively in swimming training does not induce in children changes in HRV indices. Neither time nor domain HRV variables were significantly different between untrained and highly trained prepubertal boys. Thus, intensive training in healthy children does not involve deleterious effects on HRV.

Pollution is known to particularly affect patients with respiratory insufficiency and right ventricle abnormalities. We therefore hypothesized that carbon monoxide (CO) at low dose could be involved in cardiovascular disorders in patients with chronic hypoxic pulmonary hypertension secondary to chronic hypoxia. Ten-week-old male and female healthy Dark Agouti rats were randomly divided into two series--untrained (U) and trained (T)--of four groups of 18 animals each. Both U and T series were continuously exposed to ambient air (U(AIR), and T(AIR); n = 16) or air plus 50 ppm CO (U(AIR+CO) and T(AIR+CO); n = 18). Similarly, rats initially subjected to right ventricle hypertrophy secondary to chronic hypoxia (H) were continuously exposed to ambient air (TH(AIR), and UH(AIR); n = 18) or air plus 50 ppm CO (UH(AIR+CO), and TH(AIR+CO); n = 18). Doppler-echocardiography and hemodynamic studies performed at rest both indi-cated that CO had no significant effect on cardiac morphology or functions in control rats (U(AIR+CO) vs U(AIR)). In contrast, cardiac dilation and large decreases in left ventricular ejection fraction, mitral early diastolic rapid inflow (E) deceleration, E/atrial contraction filling (A) ratio, +dP/dt, and -dP/dt were found in TH(AIR+CO) compared with TH(AIR). After exposure, heart rate variability was unaffected in U(AIR+CO), whereas total power spectra were markedly decreased and low frequency/high frequency power ratio was increased in TH(AIR+CO) rats. CO pollution could be directly involved in cardiac disorders of patients with pre-existent hypertrophic cardiomyopathies.

The purpose of this study was to compare O2 uptake [Formula: see text] and muscle electromyography activity kinetics during moderate and severe exercise to test the hypothesis of progressive recruitment of fast-twitch fibers in the explanation of the [Formula: see text] slow component. After an incremental test to exhaustion, 7 trained cyclists (mean ± SD, 61.4 ± 4.2 ml•min−1•kg−1) performed several square-wave transitions for 6 min at moderate and severe intensities on a bicycle ergometer. The [Formula: see text] response and the electrical activity (i.e., median power frequency, MDF) of the quadriceps vastus lateralis and vastus medialis of both lower limbs were measured continuously during exercise. After ∼2 to 3 min of exercise onset, MDF values increased similarly during moderate and severe exercise for almost all muscles whereas a [Formula: see text] slow component occurred during severe exercise. There was no relationship between the increase of MDF values and the magnitude of the [Formula: see text] slow component during the severe exercise. These results suggest that the origin of the slow component may not be due to the progressive recruitment of fast-twitch fibers. Key words: median power frequency, O2 uptake, recruitment of fast-twitch fibers, [Formula: see text]slow component

In order to assess possible influences of socioeconomic status and gender on habitual physical activity (HPA) of prepubertal French children, daily heart rate was 24-hr-monitored in 65 normal subjects for 2 days in the same school week. HPA was evaluated as the mean daily time spent at heart rates greater than 140 bpm (tFC > 140), 160 bpm (tFC > 160), 50% (tFC > 50%), and 70% (tFC > 70%) of the heart rate reserve. An effect of socioeconomic status (determined by questionnaire) was found in boys, with HPA being greater in the underprivileged ones (tFC > 140: 51.8 ± 30.1 vs 33.0 ± 14.1 min, p FC > 160: 22.7 ± 16.6 vs 11.1 ± 7.4 min, p FC > 50%: 61.4 ± 33.5 vs 46.5 ± 17.1 min, p FC > 70%: 20.1 ± 15.2 vs 10.6 ± 7.1, p FC > 140: 51.8 ± 30.1 vs 32.8 ± 26.0 min, tFC > 160: 22.7 ± 16.6 vs 9.9 ± 8.2 min, p FC > 50%: 61.4 ± 33.5 vs 37.4 ± 23.8 min, p FC > 70%: 20.1 ± 15.2 vs 8.1 ± 6.3, p

Background The aim of the present study was to evaluate the effect of an endurance training program on heart rate variability (HRV) in prepubertal healthy children and to determine the relationships between HRV components and training-induced cardiac adaptations. Methods Nineteen prepubertal children (aged 10–11 years old) took part in this study: 12 children were assigned to participate in a 13-week endurance training program (3 × 1 h week−1; intensity, > 80% HRmax) and 7 children served as a control group. Before and after the 13-week study period, all the children were tested for maximal oxygen uptake (V O2max), HRV was measured by spectral and time domain analysis of 5 h night ECG recordings, and left ventricular (LV) cardiac morphology and function were assessed by means of Doppler-Echocardiography. Results V O2max increased significantly (+15·5% ± 12·1; P

Stroke volume response to exercise depends on changes in cardiac filling, intrinsic myocardial contractility, and left ventricular afterload. The purpose of this study was to compare these responses during an upright cycle test performed until exhaustion in children and adults.Stroke volume, cardiac output (Doppler echocardiography), left ventricular dimensions (two-dimensional and time-movement echocardiography), as well as arterial pressure and systemic vascular resistance (SVR) were assessed in 17 boys (mean age, 11.7 +/- 0.6 yr) and 23 young adult men (mean age, 21.2 +/- 2.7 yr) having a similar aerobic potential. All variables were measured at the end of the resting period, during the final minute of each workload, and during the last minute of the test.No significant differences were obtained for stroke volume, cardiac output, and left ventricular dimensions when they were scaled to body surface area at rest and whatever the exercise intensity. However, arteriovenous oxygen uptake was higher and the SVR lower in the adults than in the children.The patterns of stroke volume, as well as its underlying mechanisms, were not age-related during an upright maximal exercise test. However, other studies are required to understand further the effect of pubertal status on the peripheral cardiovascular system.

Insights into both normal and pathological cardiac responses to exercise have been hampered by lack of a safe, accurate, feasible means of estimating cardiac output (Q) during high-intensity and maximal exercise. Doppler ultrasound noninvasively measures blood velocity as it exits the heart and can be performed during exhaustive exercise without interference of the subject or need for steady state. From the product of aortic blood velocity and cross-sectional area of the aorta, stroke volume (SV) can be calculated. Despite these advantages of the Doppler technique, a number of potential sources of error have raised concern regarding the accuracy of this method. These include transducer angulation, change in aortic cross-sectional area during exercise, turbulence and alteration of a flat velocity profile in the aorta with increased Q, and uncertainties regarding the proper location for measurement of aortic outflow area. The magnitude of the influence of these potentially confounding variables on the accuracy of SV measurements determined by the Doppler technique is unknown. Estimates of both construct and concurrent validity suggest that the overall error may be small. Test-retest studies have indicated a high level of reliability with this technique.

Stabilization of the Hypoxia Inducible Factor (HIF) using prolyl-hydroxylase inhibitors (PHI) leads to an EPO synthesis which is suspected to be used as a doping practice. Such a treatment is suspected to improve endurance performance by increasing oxygen transport. However the effects of a PHI treatment on heart morphology and function has never been investigated. Therefore the aim of this study was to evaluate whether potential effects of PHI on cardiac function could contribute to explain its beneficial effect on aerobic performance.We tested the effects of a 1 week treatment with a PHI (DMOG, 150mg.kg–1, I.P.) or a placebo (NaCl) on both sedentary (Sed) and trained rats (Ex; trained during 5 weeks before treatment started; 40min at 25m.min–1 per day; 5days/week). Our first result was that PHI increased running performance (+12%, p

International audience; Background: Growing evidence demonstrates subtle left ventricular myocardial dysfunction in patients with metabolic syndrome (MetS), with central obesity, glucose intolerance and inflammation emerging as important contributors. Whether these results can be translated to the right ventricle (RV) is not yet fully elucidated. Furthermore, although lifestyle intervention favorably impacts MetS components and inflammatory biomarkers, its effect on RV myocardial function remains unknown today. Methods: Thirty-nine MetS adults free of diabetes were enrolled in a three month lifestyle intervention program including diet and physical exercise, and compared with forty healthy controls. Blood biochemistry, echocardiography including tissue Doppler imaging (TDI), and vector velocity imaging of the RV free wall to assess global longitudinal strain (GLS) and strain rates (SR) were obtained at baseline and after the intervention. Results: Compared with controls, MetS patients presented similar right atrial and RV morphology but reduced systolic (P = 0.04) and early diastolic (P = 0.02) velocities of the tricuspid annulus. They showed attenuated RV GLS (−21.4 ± 4.5vs-25.7 ± 4.9%, P < 0.001) as well as early diastolic (P = 0.003) and systolic (P < 0.001) SR. Multiple regression analyses revealed log PAI-1 active, (P < 0.001), log adiponectin, (P = 0.01), LV mass indexed (P = 0.004) and central fat (P = 0.03) as independent predictors of RV GLS (R 2 = 0.46, P < 0.001). Biological markers of MetS and inflammation as well as RV GLS (−21.8 ± 3.8vs-24.3 ± 3.0%, P = 0.009) and systolic (P = 0.003) and early diastolic (P = 0.01) SR, but not TDI indexes, significantly improved after diet and exercise training, and vector velocity imaging data in MetS following the lifestyle intervention no longer differed from controls. Conclusions: MetS is associated with subtle impairments in both RV free wall diastolic and systolic myocardial function which could be partly related to central-obesity induced changes in pro-and anti-inflammatory cytokines and left ventricular remodeling. The favorable impact of healthy dieting and physical activity on RV free wall mechanics indicates that cellular and sub-cellular alterations responsible for the RV myocardial abnormalities are probably not permanent and modifiable throughout adequate interventional strategies. Trial registration: American National Institutes of Health database NCT00917917.

Background We aimed to comprehensively evaluate lipoprotein profile including lipid particle size following a lifestyle intervention in metabolic syndrome (MetS) volunteers and to assess the associations between lipoprotein subfractions and carotid-intima-media-thickness (CIMT) – a surrogate indicator of atherogenesis. Methods 100 participants (50–70 years) from the RESOLVE trial, underwent a one-year follow-up beginning with a three-week residential program combining high exercise volume (15-20 h/week), restrictive diet (-500 kcal/day), and education. For baseline references, 40 aged-matched healthy controls were recruited. Independent associations between subfractions of lipoproteins and CIMT were evaluated using a generalized estimating equations model accounting for variation in correlations between repeated measures. The lipoprotein subfractions profile was assessed using Lipoprint® electrophoresis allowing to separate: the very low-density lipoprotein (VLDL) fraction, then the intermediate-density lipoprotein (IDL) C, B and A, the low-density lipoprotein (LDL) with subfractions 1 and 2 as large LDL and subfractions 3 to 7 as small dense LDL (sdLDL), and the high density lipoprotein (HDL) subfractions categorized into large, intermediate, and small HDL. Apolipoproteins A1 and B were also measured. Results 78 participants completed the program. At baseline, apolipoproteins B/A1, VLDL, sdLDL and small HDL were higher in MetS than in healthy controls; IDL, LDL size, large and intermediate HDL were lower. Despite time-related regains during the follow-up, lipoprotein subfractions traditionally involved in cardiovascular risk, such as sdLDL, improved immediately after the residential program with values closest to those of healthy controls. CIMT improved throughout the lifestyle intervention. Using a generalized estimating equations model, none of the subfractions of lipoproteins nor apolipoproteins were linked to CIMT. Conclusions Lipoprotein subfractions traditionally involved in CVR, decreased after the 3-week residential program. During a 12 month follow-up, the time-related regains remained closer to the values of healthy controls than they were at baseline. CIMT improved throughout the lifestyle intervention. However, we failed to demonstrate a link between some lipoprotein subfractions and the atherogenicity directly measured from the wall thickness of arteries (CIMT). Further investigations are required to explore the atherogenicity of lipoprotein subfractions. Trial registration NCT00917917

Context and Objective: Impaired insulin-dependent vasodilation might contribute to microvascular dysfunction of metabolic syndrome (MetS). The aims of this study were to assess the insulin vasoreactivity in MetS, and to evaluate the effects of a lifestyle program. Design, Setting, Participants, and Outcome Measures: Laser Doppler measurements were used to assess cutaneous blood flux (CBF) and flowmotion in response to iontophoresis of insulin and acetylcholine (ACh) in 38 MetS and 18 controls. Anthropometric, plasma insulin, glycemia, and inflammatory markers were measured. MetS subjects (n = 24) underwent a 6-month lifestyle intervention (M6) with a 3-week residential program (D21). Results: The absolute and relative peak insulin and ACh CBF were significantly higher in controls than in MetS subjects. Significant inverse correlations were found between peak insulin CBF and glycemia, insulin and glycated hemoglobin, active plasminogen activator inhibitor-1 (PAI-1), C-reactive protein (CRP), and IL-6. With respect to flowmotion, MetS subjects showed lower values in total spectrum CBF and in all its components (except respiratory one). At D21 and M6, peak insulin CBF increased and was no longer different from control values whereas peak ACh CBF did not change. From D21, all the different components and the total CBF spectrum became similar to the control values. The changes in peak insulin CBF and in endothelial component between M6 and baseline were inversely correlated with the change in CRP and PAI-1. Conclusions: The local vasodilatory effects to insulin and its overall flowmotion are impaired in MetS subjects in relation to inflammation. The lifestyle intervention reversed this insulin-induced vascular dysfunction in parallel to decreased inflammation level.

The aim of this study was to assess the effects of vigorous activity on the somatic and skeletal growths in young females reaching puberty. From a group of 41 prepubertal girls, 24 remained in this study: 10 gymnasts training 15 to 22 hr a week and 14 non-exercising controls. At the start and during the study period, bone age, height, weight, fat and lean mass were significantly lower in the gymnasts vs. the controls (p < .05). These variables had increased in the same way for both groups. At each investigation, the gymnasts had significantly higher BMC, BMD, and BMAD at all the sites (p < .01) except the whole body. The strong correlation between somatic measurements at the start and at the end of the study indicated that physical exercise does not disrupt the normal growth in these children.

The aim of this study was to examine the reproducibility of cardiac output (Q) measured by Doppler echocardiography and CO2-rebreathing in prepubertal children during exercise. Fourteen healthy children (8 girls and 6 boys aged 10.9 ± 0.9 years) underwent a progressive maximum upright cycle test until exhaustion on two separate occasions (1 week apart). Q was determined successively by the two methods at rest and during the final minutes of each workload. The reproducibility of the Doppler method was higher than the reproducibility of the CO2-rebreathing method, both at rest and during exercise. Moreover, this reproducibility was lower during high intensity exercise whatever the method used. On account of its high reproducibility, Doppler echocardiography should be preferentially used to detect changes in Q as a result of an exercise training intervention in prepubertal children.

Hydroxytyrosol (HT) and Resveratrol (RES) are recognized as strong antioxidant polyphenolic compound. While RES antioxidative mechanisms are well known, those of HT are controversial because of its low intestinal absorption and its high metabolisation in glucuronides (GC), suggesting that these metabolites are susceptible to express HT biologicial activity in vivo. Our objective was to compare the vasorelaxant effect of Res, HT and GC on isolated aortic from young males Wistar rats (3months), old Wistar and GK rats (14 months), in presence or not of t-BOOH-induced oxidative stress (1mM; 30min). No vasorelaxant effect of the polyphenols was observed in young or old males Wistar rats. However, in old GK rats, Res and GC had significant vasorelaxant effect. In response to t-BOOH-induced oxidative stress, HT and RES protected the aortic rings of young Wistar rats (p < 0.05). However, different maximal relaxation was found between HT + t-BOOH, Res + t-BOOH and Control (72.5±2.8%, 76.1%±7.7% vs 88.8±0.7% ; p

In adults, left ventricular (LV) systolic twist is an important factor that determines LV filling, both at rest and during exercise. In children, lower LV twist has been demonstrated at rest, but its adaptation during exercise and its functional consequences on LV filling are unknown. Using speckle-tracking echocardiography, LV twist-untwist mechanics were studied in 25 children (aged 10-12 years) and 20 young adults (aged 18-44 years) at rest and during three exercise workloads performed at 20%, 30%, and 40% of their maximal aerobic power. At rest, LV twist was lower in children, because of a higher temporal dispersion of peak rotation between base and apex. During exercise, the increase of basal rotation was blunted in children compared with adults (-6.7 ± 2.7° vs -9.0 ± 2.0° at 40% of maximal aerobic power, P < .05). Consequently, LV twist increased to a lesser extent (13.0 ± 5.0° vs 15.8 ± 4.5° at 40% of maximal aerobic power, P < .05). The increase in LV untwisting rates during exercise was also lower in children, leading to a lower percentage of untwisting during early diastole (8 ± 8% vs 29 ± 20% at 40% of maximal aerobic power, P < .001). Consequently, during early diastole, the normal timing of diastolic events observed in young adults, with untwist occurring before radial displacement, was blunted in children. Nevertheless, children exhibited normal LV filling due to higher diastolic radial and longitudinal strain rates. Twist-untwist mechanics may evolve with advancing age. In children, early diastolic LV untwisting appears to be less important than in adults. Their better LV intrinsic myocardial relaxation may ensure adequate LV filling during exercise without dependence on the additional effect of suction resulting from LV energy recoil. 26;11

International audience; a r t i c l e i n f o Background: Opinions differ over the exercise modalities that best limit cardiovascular risk (CVR) resulting from visceral obesity in individuals with metabolic syndrome (MetS). As little is known about the combined effects of resistance and endurance training at high volumes under sound nutritional conditions, we aimed to analyze the impact of various intensities of physical activity on visceral fat and CVR in individuals with MetS. Methods: 100 participants, aged 50–70 years, underwent a diet restriction (protein intake 1.2 g/kg/day) with a high exercise volume (15–20 h/week). They were randomized to three training groups: moderate-resistance–moderate-endurance (re), high-resistance–moderate-endurance (Re), or moderate-resistance– high-endurance (rE). A one-year at-home follow-up (M12) commenced with a three-week residential program (Day 0 to Day 21). We measured the change in visceral fat and body composition by DXA, MetS parameters , fitness, the Framingham score and carotid-intima–media-thickness. Results: 78 participants completed the program. At D21, visceral fat loss was highest in Re (−18%, p b .0001) and higher in rE than re (− 12% vs. − 7%, p b .0001). Similarly, from M3, visceral fat decreased more in high-intensity-groups to reach a visceral fat loss of −21.5% (Re) and − 21.1% (rE) > −13.0% (re) at M12 (p b .001). CVR, MetS parameters and fitness improved in all groups. Visceral fat loss correlated with changes in MetS parameters. Conclusion: Increased intensity in high volume training is efficient in improving visceral fat loss and carotid-intima–media-thickness, and is realistic in community dwelling, moderately obese individuals. High-intensity-resistance training induced a faster visceral fat loss, and thus the potential of resistance training should not be undervalued (ClinicalTrials.gov number: NCT00917917).