Contrary to earlier smaller trials, we observed similar improvements in exercise capacity and peripheral endothelial function following AIT and ACT in a large population of CAD patients.

BackgroundNumerous meta-analyses have investigated the effect of exercise in different populations and for single cardiovascular risk factors, but none have specifically focused on the metabolic syndrome (MetS) patients and the concomitant effect of exercise on all associated cardiovascular risk factors.ObjectiveThe aim of this article was to perform a systematic review with a meta-analysis of randomized and clinical controlled trials (RCTs, CTs) investigating the effect of exercise on cardiovascular risk factors in patients with the MetS.MethodsRCTs and CTs ≥4 weeks investigating the effect of exercise in healthy adults with the MetS and published in a peer-reviewed journal up to November 2011 were included. Primary outcome measures were changes in waist circumference (WC), systolic and diastolic blood pressure, high-density lipoprotein cholesterol (HDL-C), triglycerides and fasting plasma glucose. Peak oxygen uptake () was a secondary outcome. Random and fixed-effect models were used for analyses and data are reported as means and 95% confidence intervals (CIs).ResultsSeven trials were included, involving nine study groups and 206 participants (128 in exercise group and 78 in control group). Significant mean reductions in WC −3.4 (95% CI −4.9, −1.8) cm, blood pressure −7.1 (95% CI −9.03, −5.2)/−5.2 (95% CI −6.2, −4.1) mmHg and a significant mean increase in HDL-C +0.06 (95% CI +0.03, +0.09) mmol/L were observed after dynamic endurance training. Mean plasma glucose levels −0.31 (95% CI −0.64, 0.01; p = 0.06) mmol/L and triglycerides −0.05 (95% CI −0.20, 0.09; p = 0.47) mmol/L remained statistically unaltered. In addition, a significant mean improvement in of +5.9 (95% CI +3.03, +8.7) mL/kg/min or 19.3% was found.ConclusionsOur results suggest that dynamic endurance training has a favourable effect on most of the cardiovascular risk factors associated with the MetS. However, in the search for training programmes that optimally improve total cardiovascular risk, further research is warranted, including studies on the effects of resistance training and combined resistance and endurance training.

In a previous paper, as the first of a series of three on the importance of characteristics and modalities of physical activity (PA) and exercise in the management of cardiovascular health within the general population, we concluded that, in the population at large, PA and aerobic exercise capacity clearly are inversely associated with increased cardiovascular disease risk and all-cause and cardiovascular mortality and that a dose–response curve on cardiovascular outcome has been demonstrated in most studies. More and more evidence is accumulated that engaging in regular PA and exercise interventions are essential components for reducing the severity of cardiovascular risk factors, such as obesity and abdominal fat, high BP, metabolic risk factors, and systemic inflammation. However, it is less clear whether and which type of PA and exercise intervention (aerobic exercise, dynamic resistive exercise, or both) or characteristic of exercise (frequency, intensity, time or duration, and volume) would yield more benefit for each separate risk factor. The present paper, therefore, will review and make recommendations for PA and exercise training in the management of cardiovascular health in individuals with cardiovascular risk factors. The guidance offered in this series of papers is aimed at medical doctors, health practitioners, kinesiologists, physiotherapists and exercise physiologists, politicians, public health policy makers, and individual members of the public. Based on previous and the current literature overviews, recommendations from the European Association on Cardiovascular Prevention and Rehabilitation are formulated regarding type, volume, and intensity of PA and regarding appropriate risk evaluation during exercise in individuals with cardiovascular risk factors.

We thank Drs Yoneyama and Akashi for their important reference to the confounding influence of respiration on biventricular volume assessment by real-time cardiac magnetic resonance imaging. As we noted in the Discussion, changes in biventricular volumes "may be caused by physiological differences in preload attributable to the fall in intrathoracic pressures during inspiration and cardiac translation through the imaging plane."1 Real-time cardiac magnetic resonance imaging provides a novel means of expanding on the eloquent work of Natarajan et al 2 on assessing the influence of the respiratory pump on cardiac filling and function. This interaction between breathing and cardiac function has received limited attention, but now we have an excellent noninvasive tool for very accurately detailing changes in both right and left ventricular volumes with various respiratory maneuvers. We hope to provide novel data in the peer-reviewed literature soon that will detail the importance of this respiratory pump in enhancing cardiac filling. We slightly disagree with the assertion that breath-hold imaging should be considered a gold standard. Breath-holding is a nonphysiological surrogate that has previously been necessary to enable gating of cardiac magnetic resonance images. Real-time imaging enables the investigator to apply the accuracy of cardiac magnetic resonance to real physiological settings. We can neither ignore the fact that our patients breathe nor ignore the fact that most of our patients develop symptoms with exertion. This new methodology finally enables us to accurately measure cardiac function when it really matters. DisclosuresNone. References

In CAD patients with preserved and/or reduced LVEF, AIT is superior to MCT for improving peakVO2, while MCT seems to be more effective in reducing body weight. However, large, well-designed, randomized controlled trials are warranted to confirm these findings.