The influence of training characteristics on the effect of aerobic exercise training in patients with chronic heart failure: A meta-regression analysis

Comparison of exercise training modalities and change in peak oxygen consumption in heart failure with preserved ejection fraction: a secondary analysis of the OptimEx-Clin trial

AIMS

Exercise training (ET) is an effective therapy in heart failure with preserved ejection fraction (HFpEF), but the influence of different ET characteristics is unclear. We aimed to evaluate the associations between ET frequency, duration, intensity [% heart rate reserve (%HRR)] and estimated energy expenditure (EEE) with the change in peak oxygen consumption (V̇O2) over 3 months of moderate continuous training (MCT, 5×/week) or high-intensity interval training (HIIT, 3×/week) in HFpEF.

METHODS AND RESULTS

ET duration and heart rate (HR) were recorded with a smartphone application. EEE was calculated using the HR data during ET and the individual HR-V̇O2 relationships during cardiopulmonary exercise testing. Differences between groups and associations between ET characteristics and peak V̇O2 change were assessed with linear regression analyses. Peak V̇O2 improved by 9.2 ± 13.2% after MCT and 8.7 ± 15.9% after HIIT (P = 0.67). The average EEE of 1 HIIT session was equivalent to ∼1.42 MCT sessions and when adjusted for EEE, the mean difference between MCT and HIIT was -0.1% (P = 0.98). For both MCT and HIIT, peak V̇O2 change was positively associated with ET frequency (MCT: R2 = 0.103; HIIT: R2 = 0.149) and duration/week (MCT: R2 = 0.120; HIIT: R2 = 0.125; all P < 0.05). Average %HRR was negatively associated with peak V̇O2 change in MCT (R2 = 0.101; P = 0.034), whereas no significant association was found in HIIT (P = 0.234). Multiple regression analyses explained ∼1/3 of the variance in peak V̇O2 change.

CONCLUSION

In HFpEF, isocaloric HIIT and MCT seem to be equally effective over 3 months. Within each mode, increasing ET frequency or duration/week may be more effective to improve peak V̇O2 than increasing ET intensity.

Effects of Exercise Training Response on Quality of Life and Cardiovascular Risk Factor Profiles in People With Coronary Artery Disease: Insights From the HIIT or MISS UK Trial

OBJECTIVE

To compare the characteristics of responders and nonresponders to 8 weeks of exercise training to determine differences in key cardiovascular disease outcomes in people with coronary artery disease (CAD).

DESIGN

Secondary analysis of data from the HIIT or MISS UK trial.

SETTING

Six outpatient National Health Service cardiac rehabilitation (CR) centers in the UK. In people with CAD attending CR, the HIIT or MISS UK trial reported that short-term, low-volume, high-intensity interval training (HIIT) was more effective than moderate-intensity steady state (MISS) exercise training for improving peak oxygen uptake (V̇o2peak).

PARTICIPANTS

382 participants with CAD (N=382) (mean age: 58.8±9.6y; mean body mass index: 29.0±4.3 kg/m2).

MAIN OUTCOME MEASURES

We identified responders and nonresponders based on a meaningful change in V̇o2peak, using 2 established methods. Key clinical, quality of life (QoL), and cardiopulmonary exercise test (CPET)-derived outcomes were compared between groups.

RESULTS

Responders were more likely to be younger (P<.05), and demonstrate greater improvement in CPET-related outcomes, for example, oxygen uptake efficiency slope, ventilatory efficiency, and peak power output (all comparisons, P<.001). Responders were more likely to observe improvements in QoL (EQ-5D-5L; mean Δ 13.6 vs mean Δ 9.4; P=.045), and high-density lipoprotein cholesterol (HDL-c) (mean Δ 0.09 mmol/L vs mean Δ 0.04 mmol/L; P=.004), compared to nonresponders.

CONCLUSIONS

In people with CAD attending CR, responders to exercise training were more likely to be younger and demonstrate greater improvements in health-related QoL and HDL-c.

Exercise-based cardiac rehabilitation for adults with heart failure

BACKGROUND

People with heart failure experience substantial disease burden that includes low exercise tolerance, poor health-related quality of life (HRQoL), increased risk of mortality and hospital admission, and high healthcare costs. The previous 2018 Cochrane review reported that exercise-based cardiac rehabilitation (ExCR) compared to no exercise control shows improvement in HRQoL and hospital admission amongst people with heart failure, as well as possible reduction in mortality over the longer term, and that these reductions appear to be consistent across patient and programme characteristics. Limitations noted by the authors of this previous Cochrane review include the following: (1) most trials were undertaken in patients with heart failure with reduced (< 45%) ejection fraction (HFrEF), and women, older people, and those with heart failure with preserved (≥ 45%) ejection fraction (HFpEF) were under-represented; and (2) most trials were undertaken in a hospital or centre-based setting.

OBJECTIVES

To assess the effects of ExCR on mortality, hospital admission, and health-related quality of life of adults with heart failure.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, PsycINFO and Web of Science without language restriction on 13 December 2021. We also checked the bibliographies of included studies, identified relevant systematic reviews, and two clinical trials registers.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared ExCR interventions (either exercise only or exercise as part of a comprehensive cardiac rehabilitation) with a follow-up of six months or longer versus a no-exercise control (e.g. usual medical care). The study population comprised adults (≥ 18 years) with heart failure - either HFrEF or HFpEF.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were all-cause mortality, mortality due to heart failure, all-cause hospital admissions, heart failure-related hospital admissions, and HRQoL. Secondary outcomes were costs and cost-effectiveness. We used GRADE to assess the certainty of the evidence.

MAIN RESULTS

We included 60 trials (8728 participants) with a median of six months' follow-up. For this latest update, we identified 16 new trials (2945 new participants), in addition to the previously identified 44 trials (5783 existing participants). Although the existing evidence base predominantly includes patients with HFrEF, with New York Heart Association (NYHA) classes II and III receiving centre-based ExCR programmes, a growing body of trials includes patients with HFpEF with ExCR undertaken in a home-based setting. All included trials employed a usual care comparator with a formal no-exercise intervention as well as a wide range of active comparators, such as education, psychological intervention, or medical management. The overall risk of bias in the included trials was low or unclear, and we mostly downgraded the certainty of evidence of outcomes upon GRADE assessment. There was no evidence of a difference in the short term (up to 12 months' follow-up) in the pooled risk of all-cause mortality when comparing ExCR versus usual care (risk ratio (RR) 0.93, 95% confidence interval (CI) 0.71 to 1.21; absolute effects 5.0% versus 5.8%; 34 trials, 36 comparisons, 3941 participants; low-certainty evidence). Only a few trials reported information on whether participants died due to heart failure. Participation in ExCR versus usual care likely reduced the risk of all-cause hospital admissions (RR 0.69, 95% CI 0.56 to 0.86; absolute effects 15.9% versus 23.8%; 23 trials, 24 comparisons, 2283 participants; moderate-certainty evidence) and heart failure-related hospital admissions (RR 0.82, 95% CI 0.49 to 1.35; absolute effects 5.6% versus 6.4%; 10 trials; 10 comparisons, 911 participants; moderate-certainty evidence) in the short term. Participation in ExCR likely improved short-term HRQoL as measured by the Minnesota Living with Heart Failure (MLWHF) questionnaire (lower scores indicate better HRQoL and a difference of 5 points or more indicates clinical importance; mean difference (MD) -7.39 points, 95% CI -10.30 to -4.77; 21 trials, 22 comparisons, 2699 participants; moderate-certainty evidence). When pooling HRQoL data measured by any questionnaire/scale, we found that ExCR may improve HRQoL in the short term, but the evidence is very uncertain (33 trials, 37 comparisons, 4769 participants; standardised mean difference (SMD) -0.52, 95% CI -0.70 to -0.34; very-low certainty evidence). ExCR effects appeared to be consistent across different models of ExCR delivery: centre- versus home-based, exercise dose, exercise only versus comprehensive programmes, and aerobic training alone versus aerobic plus resistance programmes.

AUTHORS' CONCLUSIONS

This updated Cochrane review provides additional randomised evidence (16 trials) to support the conclusions of the previous 2018 version of the review. Compared to no exercise control, whilst there was no evidence of a difference in all-cause mortality in people with heart failure, ExCR participation likely reduces the risk of all-cause hospital admissions and heart failure-related hospital admissions, and may result in important improvements in HRQoL. Importantly, this updated review provides additional evidence supporting the use of alternative modes of ExCR delivery, including home-based and digitally-supported programmes. Future ExCR trials need to focus on the recruitment of traditionally less represented heart failure patient groups including older patients, women, and those with HFpEF.

High intensity interval training vs. moderate intensity continuous training on aerobic capacity and functional capacity in patients with heart failure: a systematic review and meta-analysis

Background

Exercise training is commonly employed as a efficacious supplementary treatment for individuals suffering from heart failure, but the optimal exercise regimen is still controversial. The objective of the review was to compare the effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on the exercise capacity, cardiac function, quality of life (QoL) and heart rate among patients with heart failure with reduced ejection fraction.

Methods

A systematic search was performed using the following eight databases from their inception to July 5, 2023: PubMed, Web of Science, Embase, Cochrane Library, Clinical Trials, China Knowledge Network, Wan fang Data, and the China Biology Medicine databases. The meta-analysis results were presented as mean difference (MD) and 95% confidence interval (CI). The Cochrane Risk of Bias tool was used for the included studies. The Grading of Recommendations Assessment, Development, and Evaluations was used to assess the certainty of evidence.

Results

Thirteen randomized controlled trials were included in the study. The results showed that HIIT had a significant positive effect on peak oxygen uptake (MD = 1.78, 95% CI for 0.80-2.76), left ventricular ejection fraction (MD = 3.13, 95% CI for 1.25-5.02), six-minute walk test (MD = 28.13, 95% CI for 14.56-41.70), and Minnesota Living with Heart Failure Questionnaire (MD = -4.45, 95% CI for -6.25 to -2.64) compared to MICT. However, there were no statistically significant differences observed in resting heart rate and peak heart rate.

Conclusions

HIIT significantly improves peak oxygen uptake, left ventricular ejection fraction, six-minute walk test, and Minnesota Living with Heart Failure Questionnaire in patients with heart failure with reduced ejection fraction. Additionally, HIIT exhibits greater effectiveness in improving peak oxygen uptake among patients with lower body mass index.

Systematic Review Registration

https://www.doi.org/10.37766/inplasy2023.7.0100, identifier (INPLASY2023.7.0100).

Appropriate exercise prescription in primary and secondary prevention of cardiovascular disease: why this skill remains to be improved among clinicians and healthcare professionals. A call for action from the EXPERT Network†

In Europe alone, on a yearly basis, millions of people need an appropriate exercise prescription to prevent the occurrence or progression of cardiovascular disease (CVD). A general exercise recommendation can be provided to these individuals (at least 150 min of moderate-intensity endurance exercise, spread over 3-5 days/week, complemented by dynamic moderate-intensity resistance exercise 2 days/week). However, recent evidence shows that this one size does not fit all and that individual adjustments should be made according to the patient's underlying disease(s), risk profile, and individual needs, to maximize the clinical benefits of exercise. In this paper, we (i) argue that this general exercise prescription simply provided to all patients with CVD, or elevated risk for CVD, is insufficient for optimal CVD prevention, and (ii) show that clinicians and healthcare professionals perform heterogeneously when asked to adjust exercise characteristics (e.g. intensity, volume, and type) according to the patient's condition, thereby leading to suboptimal CVD risk factor control. Since exercise training is a class 1A intervention in the primary and secondary prevention of CVD, the awareness of the need to improve exercise prescription has to be raised among clinicians and healthcare professionals if optimized prevention of CVD is ambitioned.

Exercise prescription by physiotherapists to patients with cardiovascular disease is in greater agreement with European recommendations after using the EXPERT training tool

BACKGROUND

Exercise prescriptions by clinicians to patients with cardiovascular disease (CVD) often disagree with recommendations, thus requiring improvement.

AIM

To assess whether exercise prescriptions by physiotherapists to patients with CVD are better in agreement with European (ESC/EAPC) recommendations when the EXPERT (EXercise Prescription in Everyday practice & Rehabilitative Training) Training tool is used for digital educational training.

DESIGN

In a prospective non-randomized intervention study.

METHODS

Twenty-three belgian physiotherapists first prescribed exercise intensity, frequency, session duration, program duration and exercise type (endurance or strength training) for the same three patient cases, from which the agreement with ESC/EAPC recommendations (based on a maximal score of 60/per case: agreement score) was assessed. Next, they completed a one-month digital training by using the EXPERT Training tool and completed 31 ± 13 training cases. The EXPERT tool is a training and decision support system that automatically generates a (personalised) exercise prescription according to the patient's characteristics, thus integrating the exercise prescriptions for different CVDs and risk factors, all based on ESC/EAPC recommendations. Thereafter, the same three patient cases as at entry of study were filled out again, with re-assessment of level of agreement with ESC/EAPC recommendations.

RESULTS

After using the EXPERT Training tool, the physiotherapists prescribed significantly greater exercise frequencies, program durations and total exercise volumes in all three patient cases (p < 0.05). In cases 1, 2 and 3, the agreement score increased from 29 ± 9 (out of 60), 28 ± 9, and 34 ± 7 to 41 ± 9, 41 ± 10, and 45 ± 8, respectively (p < 0.001). Hence, the total agreement score increased from 91 ± 17 (out of 180) to 127 ± 19 (p < 0.001, +44 ± 32%). A lower starting agreement score and younger age correlated with a greater improvement in total agreement score (p < 0.05).

CONCLUSIONS

Exercise prescriptions to patients with CVD, generated by physiotherapists, are significantly better in agreement with European recommendations when the EXPERT Training tool is used, indicating its educational potential.

Telerehabilitation in patients with recent hospitalisation due to acute decompensated heart failure: protocol for the Tele-ADHF randomised controlled trial

BACKGROUND

Cardiac rehabilitation in patients with chronic heart failure (CHF) has favourable effects on exercise capacity, the risk at hospital (re-)admission and quality of life. Although cardiac rehabilitation is generally recommended it is still under-utilised in daily clinical practice, particularly in frail elderly patients after hospital admission, mainly due to low referral and patient-related barriers. Cardiac telerehabilitation (CTR) has the potential to partially solve these barriers. The purpose of this study is to evaluate the effects of CTR as compared to standard remote care after hospital admission on physical functional capacity in CHF patients.

METHODS

In this randomised controlled trial, 64 CHF patients will be recruited during hospitalisation for acute decompensated heart failure, and randomised to CTR combined with remote patient management (RPM) or RPM alone (1:1). All participants will start with RPM after hospital discharge for early detection of deterioration, and will be up titrated to optimal medical therapy before being randomised. CTR will start after randomisation and consists of an 18-week multidisciplinary programme with exercise training by physical and occupational therapists, supported by a (remote) technology-assisted dietary intervention and mental health guiding by a physiologist. The training programme consists of three centre-based and two home-based video exercise training sessions followed by weekly video coaching. The mental health and dietary programme are executed using individual and group video sessions. A wrist-worn device enables remote coaching by the physical therapist. The web application is used for promoting self-management by the following modules: 1) goal setting, 2) progress tracking, 3) education, and 4) video and chat communication. The primary outcome measure is physical functional capacity evaluated by the Short Physical Performance Battery (SPPB) score. Secondary outcome measures include frailty scoring, recovery after submaximal exercise, subjective health status, compliance and acceptance to the rehabilitation programme, and readmission rate.

DISCUSSION

The Tele-ADHF trial is the first prospective randomised controlled trial designed for evaluating the effects of a comprehensive combined RPM and CTR programme in recently hospitalised CHF patients. We hypothesize that this intervention has superior effects on physical functional capacity than RPM alone.

TRIAL REGISTRATION

Netherlands Trial Registry (NTR) NL9619, registered 21 July 2021.

Predictors of Improvement in Exercise Capacity After Cardiac Rehabilitation Differ Between Octogenarian and Young-Old Patients With Acute Myocardial Infarction

BACKGROUND

Whether the magnitude and predictors of improvement in exercise capacity after cardiac rehabilitation (CR) are the same between young-old (YO) and octogenarian (OCT) patients with acute myocardial infarction (AMI) is unknown.

METHODS AND RESULTS

We studied 284 YO (age range 65-69 years; mean [±SD] 67±1 years) and 65 OCT (age range ≥80 years; mean [±SD] 83±2 years) patients who participated in a post-AMI CR program. After 3 months of CR, peak oxygen uptake (PV̇O2) measured during cardiopulmonary exercise testing improved significantly in both age groups (P<0.01), although the percentage increase in PV̇O2(%∆PV̇O2) was significantly smaller in the OCT than YO group (5.4±13.7% vs. 10.0±12.8%; P<0.01). Multiple regression analysis demonstrated that independent predictors of %∆PV̇O2were the number of outpatient CR (OPCR) sessions attended (P=0.015), left ventricular ejection fraction (P=0.028), and baseline PV̇O2(P=0.0007) in the YO group; and the number of sessions attended (P=0.018), atrial fibrillation (P=0.042), and the presence of nutritional risk (Geriatric Nutritional Risk Index ≤98; P=0.036) in the OCT group.

CONCLUSIONS

The predictors of improvement in exercise capacity after CR differed between the YO and OCT patients with AMI. To obtain a greater improvement in PV̇O2in CR, frequent OPCR session attendance may be necessary in both groups; in addition, particularly in OCT patients, better nutritional status may be important.

High-intensity training with short and long intervals regulate cortical neurotrophic factors, apoptosis markers and chloride homeostasis in rats with stroke

BACKGROUND/PURPOSE

The optimal endurance exercise parameters remain to be defined to potentiate long-term functional recovery after stroke. We aim to assess the effects of individualized high-intensity interval training (HIIT) with either long or short intervals on neurotrophic factors and their receptors, apoptosis markers and the two-main cation-chloride cotransporters in the ipsi- and contralesional cerebral cortices in rats with cerebral ischemia. Endurance performance and sensorimotor functions were also assessed METHODS: : Rats with a 2-hour transient middle cerebral artery occlusion (tMCAO) performed work-matched HIIT4 (intervals: 4min) or HIIT1 (intervals: 1min) on treadmill for 2 weeks. Incremental exercises and sensorimotor tests were performed at day 1 (D1), D8, and D15 after tMCAO. Molecular analyses were achieved in both the paretic and non-paretic triceps brachii muscles and the ipsi- and contralesional cortices at D17 RESULTS: : Gains in endurance performance are in a time-dependent manner from the first week of training. This enhancement is supported by the upregulation of metabolic markers in both triceps brachii muscles. Both regimens alter the expression of neurotrophic markers and chloride homeostasis in a specific manner in the ipsi- and contralesional cortices. HIIT acts on apoptosis markers by promoting anti-apoptotic proteins in the ipsilesional cortex CONCLUSION: : HIIT regimens seem to be of clinical relevance in the critical period of stroke rehabilitation by strongly improving aerobic performance. Also, the observed cortical changes suggest an influence of HIIT on neuroplasticity in both ipsi- and contralesional hemispheres. Such neurotrophic markers might be considered as biomarkers of functional recovery in individuals with stroke.

Effects of cardiac rehabilitation with motion assistance from a wearable cyborg hybrid assistive limb on patients with chronic heart failure: a randomized controlled trial with a one-year follow-up

[Purpose] We have recently reported that using a wearable cyborg hybrid assistive limb improved the isometric knee extensor muscle strength of patients with chronic heart failure. Here, we investigated the long-term effects of a lumbar-type hybrid assistive limb for patients with chronic heart failure. [Participants and Methods] A total of 28 hospitalized patients with chronic heart failure (mean age, 73.1 ± 13.8 years) were randomly assigned to two groups: the hybrid assistive limb group or the control group, in which they performed a sit-to-stand exercise with or without the hybrid assistive limb, respectively. The cardiac rehabilitation therapy included this intervention, which was performed as many times as possible for 5-30 minutes per day for 6-10 days. Clinical assessments like lower-limb muscle strength, walking ability, etc., were measured before and after the intervention. Cardiac events were followed up for up to a year after discharge. [Results] No adverse events occurred during the study period in either group. In terms of long-term effects, the incidence of cardiac events was 23% and 45% in the hybrid assistive limb and the control groups, respectively. [Conclusion] Hybrid assistive limb-assisted exercise therapy may be a safe and feasible cardiac rehabilitation tool in patients with chronic heart failure. The lumbar-type wearable cyborg hybrid assistive limb may have a positive effect on heart failure prognosis by adding long-term exercise therapy.

Effect of Resistance Training on Body Composition, Hemodynamic Parameters and Exercise Tolerance among Patients with Coronary Artery Disease: A Systematic Review

BACKGROUND

Effectiveness and safety of Resistance Training in treating various Cerebrovascular Disease diagnoses have drawn attention in recent years. Patients suffering with coronary artery disease should be offered individually tailored Resistance Training in their exercise regimen. Resistance Training was developed to help individuals with their functional status, mobility, physical performance, and muscle strength.

OBJECTIVE

The objective of this review was to collect, summarize and present information on the state of science focusing on usefulness, viability, safety and efficacy of Resistance Training in treating coronary artery disease and enhancing the aerobic capacity and improving overall health-related quality of life.

METHODS

The review is prepared in accordance with Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. Searches were conducted in Cochrane Library, PubMed/MEDLINE, PEDro and Scopus database. PEDro scale was used for methodological quality assessment of included studies. Two independent reviewers determined the inclusion criteria of studies by classifying interventions based on core components, outcome measures, diagnostic population and rated the quality of evidence and strength of recommendations using GRADE criteria.

RESULTS

Total 13 studies with 1025 patients were included for the detailed analysis. Findings emphasize the importance of assessing effectiveness and safety of Resistance Training in individuals with coronary artery disease. Patient specific designed exercise programs as Resistance Training targets at enhancing patients' exercise tolerance, improves hemodynamic response and muscular strength with reduction in body fat composition.

CONCLUSION

Resistance Training is an effective exercise that should be incorporated to counteract the loss of muscle strength, muscle mass, and physiological vulnerability, as well as to combat the associated debilitating effects on physical functioning, mobility and overall independence and Quality of Life during rehabilitation of patients with coronary artery disease.

Preoperative Evaluation and Care of Heart Transplant Candidates

Heart transplantation is recommended for patients with advanced heart failure refractory to medical and device therapy, and who do not have absolute contraindications. When patients become eligible for heart transplantation, they undergo comprehensive evaluation and preparation to optimize their posttransplantation outcomes. This review provides an overview of the processes that are employed to enable the candidates to be transplant-ready when donor hearts are available.

Clinician approach to cardiopulmonary exercise testing for exercise prescription in patients at risk of and with cardiovascular disease

Exercise training is highly recommended in current guidelines on primary and secondary prevention of cardiovascular disease (CVD). This is based on the cardiovascular benefits of physical activity and structured exercise, ranging from improving the quality of life to reducing CVD and overall mortality. Therefore, exercise should be treated as a powerful medicine and critical component of the management plan for patients at risk for or diagnosed with CVD. A tailored approach based on the patient's personal and clinical characteristics represents a cornerstone for the benefits of exercise prescription. In this regard, the use of cardiopulmonary exercise testing is well-established for risk stratification, quantification of cardiorespiratory fitness and ventilatory thresholds for a tailored, personalised exercise prescription. The aim of this paper is to provide a practical guidance to clinicians on how to use data from cardiopulmonary exercise testing towards personalised exercise prescriptions for patients at risk of or with CVD.

Which high-intensity interval training program is more effective in patients with coronary artery disease?

The aim of the study is to examine high-intensity interval training (HIIT) programs and a moderate-intensity continuous training (MICT) program, which are frequently used in cardiac rehabilitation programs in terms of their effects on the functional capacity and quality of life of patients with coronary artery disease (CAD). The study included 20 patients with CAD (mean age, 60.95 ± 5.08 years) who had undergone revascularization surgery. The participants were randomized into HIIT-short, HIIT-long, and MICT groups. All the groups participated in a 24-session exercise-based cardiac rehabilitation program. The participants' exercise capacity was evaluated using the maximal exercise test and estimated VO2max values, functional capacity using the 6-min walk test (6MWT), and quality of life using the Short Form-36 survey and MacNew Heart Disease Health-related Quality of Life (MacNew) questionnaire. It was determined that the estimated VO2max values statistically significantly improved after treatment (P < 0.05), and both HIIT groups were superior to the MICT group (P < 0.05). Only the HIIT groups achieved the minimal clinically important difference in the 6MWT distance. After treatment, only the MICT group had a statistically significant improvement in quality of life. There was no statistically significant difference between the groups in relation to the improvement in the 6MWT distance and quality of life (P > 0.05). The results of our study showed that both HIIT programs were superior to MICT in improving the maximal exercise capacity of patients with CAD, and the three programs had a similar effect on quality of life.

Exercise Training and Interventions for Coronary Artery Disease

Coronary artery disease (CAD) may be considered a main cause of mortality and the prevalence of CAD is increasing nowadays, leading to high health costs in many countries. Despite the fact of the regression of the atherosclerotic plaque, the decrease in blood viscosity and the growth of collateral vessels have been proposed as improvements that CAD patients may obtain under exercise performance. Thus, the present narrative review aimed to carry out a brief specific analysis of the results achieved when performing endurance, strength or inspiratory muscle training. Exercise attenuates certain pathophysiological processes of this disease, such as endothelial dysfunction or the vulnerability of atherosclerotic plaques, and produces improvements in functional capacity and muscle strength, among others. Within the different exercise modalities, the most important parameter to be considered seems to be the total caloric expenditure, and not so much the modality itself. As such, in cardiac rehabilitation, when prescribing exercise, we should possibly focus on the modality that obtains more adherence in patients. To conclude, it must be highlighted that total caloric expenditure is not being taken into account when comparing interventions and this relevant information should be considered in future studies.

Atrial Fibrillation Specific Exercise Rehabilitation: Are We There Yet?

Regular physical activity and exercise training are integral for the secondary prevention of cardiovascular disease. Despite recent advances in more holistic care pathways for people with atrial fibrillation (AF), exercise rehabilitation is not provided as part of routine care. The most recent European Society of Cardiology report for AF management states that patients should be encouraged to undertake moderate-intensity exercise and remain physically active to prevent AF incidence or recurrence. The aim of this review was to collate data from primary trials identified in three systematic reviews and recent real-world cohort studies to propose an AF-specific exercise rehabilitation guideline. Collating data from 21 studies, we propose that 360–720 metabolic equivalent (MET)-minutes/week, corresponding to ~60–120 min of exercise per week at moderate-to-vigorous intensity, could be an evidence-based recommendation for patients with AF to improve AF-specific outcomes, quality of life, and possibly prevent long-term major adverse cardiovascular events. Furthermore, non-traditional, low-moderate intensity exercise, such as Yoga, seems to have promising benefits on patient quality of life and possibly physical capacity and should, therefore, be considered in a personalised rehabilitation programme. Finally, we discuss the interesting concepts of short-term exercise-induced cardioprotection and ‘none-response’ to exercise training with reference to AF rehabilitation.

Exercise intensity assessment and prescription in cardiovascular rehabilitation and beyond: why and how: a position statement from the Secondary Prevention and Rehabilitation Section of the European Association of Preventive Cardiology

A proper determination of the exercise intensity is important for the rehabilitation of patients with cardiovascular disease (CVD) since it affects the effectiveness and medical safety of exercise training. In 2013, the European Association of Preventive Cardiology (EAPC), together with the American Association of Cardiovascular and Pulmonary Rehabilitation and the Canadian Association of Cardiac Rehabilitation, published a position statement on aerobic exercise intensity assessment and prescription in cardiovascular rehabilitation (CR). Since this publication, many subsequent papers were published concerning the determination of the exercise intensity in CR, in which some controversies were revealed and some of the commonly applied concepts were further refined. Moreover, how to determine the exercise intensity during resistance training was not covered in this position paper. In light of these new findings, an update on how to determine the exercise intensity for patients with CVD is mandatory, both for aerobic and resistance exercises. In this EAPC position paper, it will be explained in detail which objective and subjective methods for CR exercise intensity determination exist for aerobic and resistance training, together with their (dis)advantages and practical applications.

Effect of High-Intensity Interval Training on Physical Health in Coronary Artery Disease Patients: A Meta-Analysis of Randomized Controlled Trials

The effects of exercise-based cardiac rehabilitation (CR) on physical health in coronary artery disease (CAD) patients has long been established, while the optimal exercise mode remains to be determined. This meta-analysis compared the efficacy of high-intensity interval training (HIIT) versus moderate-intensity continuous training (MICT) in CAD patients. Databases were searched up to December 2020. Twenty-five studies with 1272 participants were analyzed. The results showed that both HIIT and MICT induced significant VO_2peak improvement with a 4.52 mL/kg/min (p < 0.01) and 2.36 mL/kg/min (p < 0.01), respectively. Additionally, a larger improvement of VO_2peak (1.92 mL/kg/min, p < 0.01) was observed in HIIT over MICT. HIIT with medium and long intervals, higher work/rest ratio induced larger VO_2peak improvement than the compared subgroup. Interestingly, non-isocaloric exercise protocols induced larger VO_2peak improvement compared with isocaloric protocols. In addition, both HIIT and MICT significantly increased anaerobic threshold and peak power with HIIT superior to MICT. No significant different changes were observed in blood pressure after HIIT or MICT intervention, however when HIIT was compared with MICT, MICT seems superior to HIIT in reducing systolic blood pressure (−3.61 mmHg, p < 0.01) and diastolic blood pressure (−2.37 mmHg, p < 0.01). Although, HIIT and MICT induced significant improvement of most other parameters, like HR_rest, HR_peak, left ventricular ejection fraction (LVEF), quality of life (QoL), no significant differences were noted between groups. This meta-analysis suggested that HIIT is superior to MICT in increasing VO_2peak, anaerobic threshold, peak power in CAD patients. Additionally, the efficacy of HIIT over MICT in improving VO_2peaks was influenced by HIIT intervals, work/rest ratio and total caloric consumption. Both HIIT and MICT did not significantly influence resting BP, however, MICT seemed to be more effective in reducing BP than HIIT. HIIT and MICT equally significantly influenced HR_rest, HR_peak, HRR1min, OUES, LVEF%, QoL.

Optimizing Outcomes in Cardiac Rehabilitation: The Importance of Exercise Intensity

Exercise based cardiac rehabilitation (CR) is recognized internationally as a class 1 clinical practice recommendation for patients with select cardiovascular diseases and heart failure with reduced ejection fraction. Over the past decade, several meta-analyses have generated debate regarding the effectiveness of exercise-based CR for reducing all-cause and cardiovascular mortality. A common theme highlighted in these meta-analyses is the heterogeneity and/or lack of detail regarding exercise prescription methodology within CR programs. Currently there is no international consensus on exercise prescription for CR, and exercise intensity recommendations vary considerably between countries from light-moderate intensity to moderate intensity to moderate-vigorous intensity. As cardiorespiratory fitness [peak oxygen uptake (VO₂peak)] is a strong predictor of mortality in patients with coronary heart disease and heart failure, exercise prescription that optimizes improvement in cardiorespiratory fitness and exercise capacity is a critical consideration for the efficacy of CR programming. This review will examine the evidence for prescribing higher-intensity aerobic exercise in CR, including the role of high-intensity interval training. This discussion will highlight the beneficial physiological adaptations to pulmonary, cardiac, vascular, and skeletal muscle systems associated with moderate-vigorous exercise training in patients with coronary heart disease and heart failure. Moreover, this review will propose how varying interval exercise protocols (such as short-duration or long-duration interval training) and exercise progression models may influence central and peripheral physiological adaptations. Importantly, a key focus of this review is to provide clinically-relevant recommendations and strategies to optimize prescription of exercise intensity while maximizing safety in patients attending CR programs.

Cardiac Rehabilitation in German Speaking Countries of Europe-Evidence-Based Guidelines from Germany, Austria and Switzerland LLKardReha-DACH-Part 2

Background: Scientific guidelines have been developed to update and harmonize exercise based cardiac rehabilitation (ebCR) in German speaking countries. Key recommendations for ebCR indications have recently been published in part 1 of this journal. The present part 2 updates the evidence with respect to contents and delivery of ebCR in clinical practice, focusing on exercise training (ET), psychological interventions (PI), patient education (PE). In addition, special patients’ groups and new developments, such as telemedical (Tele) or home-based ebCR, are discussed as well. Methods: Generation of evidence and search of literature have been described in part 1. Results: Well documented evidence confirms the prognostic significance of ET in patients with coronary artery disease. Positive clinical effects of ET are described in patients with congestive heart failure, heart valve surgery or intervention, adults with congenital heart disease, and peripheral arterial disease. Specific recommendations for risk stratification and adequate exercise prescription for continuous-, interval-, and strength training are given in detail. PI when added to ebCR did not show significant positive effects in general. There was a positive trend towards reduction in depressive symptoms for “distress management” and “lifestyle changes”. PE is able to increase patients’ knowledge and motivation, as well as behavior changes, regarding physical activity, dietary habits, and smoking cessation. The evidence for distinct ebCR programs in special patients’ groups is less clear. Studies on Tele-CR predominantly included low-risk patients. Hence, it is questionable, whether clinical results derived from studies in conventional ebCR may be transferred to Tele-CR. Conclusions: ET is the cornerstone of ebCR. Additional PI should be included, adjusted to the needs of the individual patient. PE is able to promote patients self-management, empowerment, and motivation. Diversity-sensitive structures should be established to interact with the needs of special patient groups and gender issues. Tele-CR should be further investigated as a valuable tool to implement ebCR more widely and effectively.

Combined aerobic and strength training for fitness outcomes in heart failure: meta-analysis and meta-regression

PURPOSE

To compare the effects of combined training (CT) versus aerobic training (AT) or versus control on VO₂ peak and quadriceps muscle strength in patients with heart failure (HF).

MATERIALS AND METHODS

Major electronic databases were searched, from inception to November 2020, for randomized clinical trials comparing the effects of CT against AT or control on VO₂ peak and/or quadriceps muscle strength in patients with HF. Random effects meta-analyses were conducted, calculating the standardized mean difference (SMD).

RESULTS

Twenty-eight articles were included. An increase on VO₂ peak (SMD = 0.77, 95%CI 0.39-1.14, I²=80.1%) and quadriceps muscle strength (SMD = 0.67, 95%CI 0.18-1.16, I²=0%) was found in CT compared to control. CT increased quadriceps muscle strength, versus AT (SMD = 0.44, 95%CI 0.15-0.74, I²=0%). There were no differences between CT and AT on VO₂ peak (SMD=-0.01, 95%CI -0.36 to 0.34, I²=65%). Time of session and training duration moderate the effects of CT over control on VO₂ peak.

CONCLUSIONS

CT promotes increases on quadriceps muscle strength and aerobic capacity over control and provides additional gains on quadriceps muscle strength, having the same effects on VO₂ peak compared to AT. A longer time of session is associated with greater benefits to aerobic capacity.Implications for rehabilitationCombining aerobic and strength training increases the functional capacity and quadriceps muscle strength in heart failure patients.Using longer sessions of training has a greater impact on aerobic capacity.

Exercise Intensity in Patients with Cardiovascular Diseases: Systematic Review with Meta-Analysis

Exercise-induced improvements in the VO₂peak of cardiac rehabilitation participants are well documented. However, optimal exercise intensity remains doubtful. This study aimed to identify the optimal exercise intensity and program length to improve VO₂peak in patients with cardiovascular diseases (CVDs) following cardiac rehabilitation. Randomized controlled trials (RCTs) included a control group and at least one exercise group. RCTs assessed cardiorespiratory fitness (CRF) changes resulting from exercise interventions and reported exercise intensity, risk ratio, and confidence intervals (CIs). The primary outcome was CRF (VO₂peak or VO₂ at anaerobic threshold). Two hundred and twenty-one studies were found from the initial search (CENTRAL, MEDLINE, CINAHL and SPORTDiscus). Following inclusion criteria, 16 RCTs were considered. Meta-regression analyses revealed that VO₂peak significantly increased in all intensity categories. Moderate-intensity interventions were associated with a moderate increase in relative VO₂peak (SMD = 0.71 mL-kg^-1-min^-1; 95% CI = [0.27-1.15]; p = 0.001) with moderate heterogeneity (I² = 45%). Moderate-to-vigorous-intensity and vigorous-intensity interventions were associated with a large increase in relative VO₂peak (SMD = 1.84 mL-kg^-1-min^-1; 95% CI = [1.18-2.50], p < 0.001 and SMD = 1.80 mL-kg^-1-min^-1; 95% CI = [0.82-2.78] p = 0.001, respectively), and were also highly heterogeneous with I² values of 91% and 95% (p < 0.001), respectively. Moderate-to-vigorous and vigorous-intensity interventions, conducted for 6-12 weeks, were more effective at improving CVD patients' CRF.

Aerobic exercise improves cardiac function in rats with chronic heart failure through inhibition of the long non-coding RNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1)

Background

To explore the beneficial effects and underlying mechanisms of aerobic exercise on chronic heart failure (CHF).

Methods

A CHF rat model was induced via left anterior descending coronary artery ligation. Four weeks post-surgery, CHF rats received aerobic exercise training over an 8-week period and cardiac function indexes including xxx were analyzed. To investigate the mechanisms involved in the aerobic exercise-induced benefits on CHF, overexpression of the long non-coding RNA MALAT1 was examined both in vivo and in vitro. Furthermore, the interaction between MALAT1 and the microRNA miR-150-5p and the downstream PI3K/Akt signaling pathway was investigated.

Results

Compared to the control group, the CHF rats showed evidence of left ventricular dysfunction including aggravated cardiac function indexes and lung to body weight ratio. The Masson staining demonstrated a significant degree of blue-stained fibrotic myocardial tissue in CHF rats compared to control rats. Furthermore, the levels of collagen I and collagen II were also markedly increased in CHF rats. Aerobic exercise improved cardiac function and left ventricular remodeling in rats with CHF. There was a significant reduction in the levels of the reactive oxygen species (ROS), inflammatory cytokines including TNF-α, IL-6, and IL-1β, and inflammatory mediums containing the matrix metalloproteinases (MMPs) MMP-2 and MMP-9. Moreover, CHF rats receiving aerobic exercise showed decreased myocardial apoptosis and increased expression of autophagy-related proteins including beclin-1 and LC3B-II. Overexpression of the lncRNA MALAT1 eliminated all the beneficial effects related to aerobic exercise in CHF rats. Subsequent investigations demonstrated that miR-150-5p expression was up-regulated in CHF-Tr rats and down-regulated in CHF-Tr-MALAT1 rats. Furthermore, the downstream PI3K/Akt signaling pathway was re-activated in CHF-Tr-MALAT1 rats. In vitro experiments revealed that overexpression of MALAT1 reduced the miR-150-5p levels, resulting in increased cellular apoptosis and less autophagy. In addition, overexpression of MALAT1 suppressed the downstream PI3K/Akt signaling pathway. Restoring miR-150-5p level with a miR-150-5p mimic decreased the cellular apoptosis and increased autophagy, and the downstream PI3K/Akt signaling pathway was re-activated.

Conclusions

Aerobic exercise improved cardiac function through inhibition of the lncRNA MALAT1 in CHF, and the potential mechanisms may be mediated via the miR-150-5p/PI3K/Akt signaling pathway.

Intensity level and cardiorespiratory responses to Baduanjin exercise in patients with chronic heart failure

AIMS

Baduanjin (eight silken movements), a traditional Chinese exercise, is an alternative to the most common cardiac rehabilitation programmes due to their scarcity and unaffordability in China. The aim of this study was to measure the intensity and energy expenditure during Baduanjin and to determine the relative oxygen consumption (VO2 ) and heart rate (HR) responses of Baduanjin compared with maximal capacity in patients with chronic heart failure.

METHODS AND RESULTS

Twenty participants (age: 65 ± 10 years, male: n = 17) with New York Heart Association II-III volunteered for this study. Participants were examined during two separate sessions, with 1-2 weeks between sessions. During session one, a symptom-limited cardiopulmonary exercise testing was performed on a cycle ergometer for measurement of maximal exercise capacity. Additionally, participants were taught Baduanjin exercise from a professional coach and were required to do it at home until the second session when their technique was confirmed by the coach. During session two, participants performed one 9 min round of Baduanjin with continuous measurement of VO2 and HR. Measurements obtained during the Baduanjin were compared with data obtained during cardiopulmonary exercise testing. While performing Baduanjin, the mean VO2 and HR were 7.1 ± 1.2 mL/kg/min and 86.1 ± 15.2 b.p.m., respectively. Compared with the cardiopulmonary exercise test, the VO2 was 44% of their VO2max and 67% of their HRmax , categorizing Baduanjin as a moderate-intensity exercise. The average energy expenditure during Baduanjin was 23.3 ± 4.4 kcal. Additionally, the VO2 and HR responses during Baduanjin both exhibited a bimodal pattern.

CONCLUSIONS

The results suggest that Baduanjin is a moderate-intensity aerobic exercise that could be an effective and safe exercise modality for home-based cardiac rehabilitation.

Cardiac cachexia: the mandate to increase clinician awareness

PURPOSE OF REVIEW

Heart failure is a frequent problem in an ageing population, associated with high rates of morbidity and mortality. Today, it is important to not only treat heart failure itself but also the related comorbidities. Among them, cardiac cachexia is one of the major challenges. It is a complex multifactorial disease with a negative impact on quality of life and prognosis. Therefore, prevention, early recognition and treatment of cardiac cachexia is essential.

RECENT FINDINGS

Cardiac cachexia frequently presents with skeletal as well as heart muscle depletion. Imaging-based diagnostic techniques can help to identify patients with cardiac cachexia and muscle wasting. Several blood biomarkers are available to detect metabolic changes in cardiac cachexia.

SUMMARY

Several studies are currently ongoing to better comprehend the underlying pathophysiological mechanisms of cardiac cachexia and to find new treatments. It is essential to diagnose it as early as possible to initiate therapy.

Observations on changes in ventricular repolarization following four weeks of exercise training in chronic heart failure patients

OBJECTIVE

The aim of this study was to investigate the effects of exercise training on ventricular repolarization dynamicity and heart rate variability in chronic heart failure patients.

DESIGN

A total of 22 chronic heart failure patients with reduced ejection fraction in sinus rhythm were included in the study. The patients were in NYHA classes II-III with an ejection fraction of 29.7 ± 7.7%. Before and after 4 weeks of aerobic exercise training, all patients performed a cardiopulmonary exercise test, a standard twelve-lead electrocardiogram and a 24 h Holter recording from which heart rate variability and ventricular repolarization dynamicity were assessed.

RESULTS

We observed a significant decrease of QTpeak (p < .001) and QTend (p < .001) at RR intervals ranging from 600 to 1000 ms on 24 h QT/RR regressions after 4 weeks of exercise training. Our analyses revealed that short-term exercise training induced significant changes in the frequency and time domain HRV parameters on an overall time-period of 24 h.

CONCLUSION

Four weeks of exercise training induced significant changes in ventricular repolarization dynamicity in chronic heart failure patients. In addition, short-term exercise training was enough to improve patients' heart rate variability.

Physical Therapist Clinical Practice Guideline for the Management of Individuals With Heart Failure

The American Physical Therapy Association (APTA), in conjunction with the Cardiovascular and Pulmonary Section of APTA, have commissioned the development of this clinical practice guideline to assist physical therapists in their clinical decision making when managing patients with heart failure. Physical therapists treat patients with varying degrees of impairments and limitations in activity and participation associated with heart failure pathology across the continuum of care. This document will guide physical therapist practice in the examination and treatment of patients with a known diagnosis of heart failure. The development of this clinical practice guideline followed a structured process and resulted in 9 key action statements to guide physical therapist practice. The level and quality of available evidence were graded based on specific criteria to determine the strength of each action statement. Clinical algorithms were developed to guide the physical therapist in appropriate clinical decision making. Physical therapists are encouraged to work collaboratively with other members of the health care team in implementing these action statements to improve the activity, participation, and quality of life in individuals with heart failure and reduce the incidence of heart failure-related re-admissions.

Impact of exercise training program attendance and physical activity participation on six minute walk distance in patients with heart failure

Background: Exercise training is recommended for all people with stable heart failure (HF) however adherence is poor. This study sought to describe exercise participation in recently hospitalized HF patients who participated in a 12-week exercise training program. The association between exercise training variables and improvement in 6-min walk distance (6MWD) was also investigated.Methods: This study is a secondary analysis of results from the intervention arm of the EJECTION-HF trial (ACTRN12608000263392), (n = 140). Exercise program attendance was defined according to session frequency (< 12 sessions vs ≥ 12 sessions) and attendance duration (< 6 weeks attendance vs ≥ 6 weeks) over the 12 weeks. Physical activity at baseline and follow up were reported according to self-report of 150 min of moderate intensity exercise per week. Primary outcome was change in 6MWD at 12 weeks.Results: Being physically active (OR 3.8, CI 1.3-11.5) and frequent program attendance (OR 2.7, CI 1.2-5.9) were associated with significant improvements in 6MWD. Program duration and baseline physical activity were not significantly associated with the outcome.Conclusions: Attainment of 150 min of moderate intensity exercise per week and at least weekly attendance at the program, were associated with significant improvements in 6MWD at follow up. Efforts should be made to assist patients with HF to achieve these targets.

Exercise-based cardiac rehabilitation in patients with reduced left ventricular ejection fraction: The Cardiac Rehabilitation Outcome Study in Heart Failure (CROS-HF): A systematic review and meta-analysis

Background

In heart failure with reduced left ventricular ejection fraction (HFrEF) patients the effects of exercise-based cardiac rehabilitation on top of state-of-the-art pharmacological and device therapy on mortality, hospitalization, exercise capacity and quality-of-life are not well established.

Design

The design of this study involved a structured review and meta-analysis.

Methods

Evaluation of randomised controlled trials of exercise-based cardiac rehabilitation in HFrEF-patients with left ventricular ejection fraction ≤40% of any aetiology with a follow-up of ≥6 months published in 1999 or later.

Results

Out of 12,229 abstracts, 25 randomised controlled trials including 4481 HFrEF-patients were included in the final evaluation. Heterogeneity in study population, study design and exercise-based cardiac rehabilitation-intervention was evident. No significant difference in the effect of exercise-based cardiac rehabilitation on mortality compared to control-group was found (hazard ratio 0.75, 95% confidence interval 0.39–1.41, four studies; 12-months follow-up: relative risk 1.29, 95% confidence interval 0.66–2.49, eight studies; six-months follow-up: relative risk 0.91, 95% confidence interval 0.26–3.16, seven studies). In addition there was no significant difference between the groups with respect to ‘hospitalization-for-any-reason’ (12-months follow-up: relative risk 0.79, 95% confidence interval 0.41–1.53, four studies), or ‘hospitalization-due-to-heart-failure’ (12-months follow-up: relative risk 0.59, 95% confidence interval 0.12–2.91, four studies; six-months follow-up: relative risk 0.84, 95% confidence interval 0.07–9.71, three studies). All studies show improvement of exercise capacity. Participation in exercise-based cardiac rehabilitation significantly improved quality-of-life as evaluated with the Kansas City Cardiomyopathy Questionnaire: (six-months follow-up: mean difference 1.94, 95% confidence interval 0.35–3.56, two studies), but no significant results emerged for quality-of-life measured by the Minnesota Living with Heart Failure Questionnaire (nine-months or more follow-up: mean difference –4.19, 95% confidence interval –10.51–2.12, seven studies; six-months follow-up: mean difference –5.97, 95% confidence interval –16.17–4.23, four studies).

Conclusion

No association between exercise-based cardiac rehabilitation and mortality or hospitalisation could be observed in HFrEF patients but exercise-based cardiac rehabilitation is likely to improve exercise capacity and quality of life.

A systematic review of recent cardiac rehabilitation meta-analyses in patients with coronary heart disease or heart failure

Aim: The aim of the project was to conduct a systematic review of meta-analyses of supervised, home-based or telemedicine-based exercise cardiac rehabilitation (CR) published between July 2011 and April 2018. Materials & methods: Evidence on mortality, hospitalization, peak VO₂, exercise capacity, muscle strength and health-related quality of life in patients with coronary heart disease or heart failure referred to CR was obtained by searching six electronic databases. Results: Of the 127 point estimates identified in the 30 CR meta-analyses identified (mortality, n = 12; hospitalization, n = 11; VO₂, n = 40; exercise capacity, n = 20; strength, n = 18; health-related quality of life, n = 26), 60% were statistically significant and 35% clinically important. Conclusion: The statistical data are sufficiently robust to promote strategies to improve referral to and participation in CR although evidence for clinical importance needs to be further investigated.

Impact of a Graded Exercise Program on V˙O2peak and Survival in Heart Failure Patients

INTRODUCTION

Although exercise therapy has the potential to improve health outcomes of patients with chronic heart failure (CHF), less than 50% of patients adhere to prescribed physical activity guidelines 1 yr after cardiac rehabilitation. We aimed to assess the effects of an extended cardiac rehabilitation program with 12 months of graded exercise therapy (GET) and resistance exercise training (RT) on exercise capacity and long-term survival in patients with CHF.

METHODS

This prospective cohort study included 60 CHF patients between 2009 and 2010. The GET-RT program consisted of exercise sessions at 6 d·wk. Total training time of aerobic exercises increased incrementally every other week without changing exercise intensity. Resistance exercise training consisted of 8 exercises with a durable resistance band. Guidance consisted of a step-down approach from in-hospital to home-based training. Cardiopulmonary exercise tests were performed at baseline, 3, 6, and 12 months. Subsequently, patients were propensity score matched on a 1:2 ratio with controls (n = 117) from a CHF registry of patients from the same clinic receiving usual out-patient care and the incidence of all-cause mortality was compared between both groups.

RESULTS

Baseline V˙O2 peak was 15.0 mL·min·kg and significantly elevated at 3 months (+1.1 mL·min·kg (95% CI, 0.4-1.8), 6 months (+2.9 mL·min·kg (95% CI, 1.1-2.9) and 12 months (+2.6 mL·min·kg (95% CI, 1.4-3.8). During 8 yr of follow-up 23 (38.3%) patients of the GET-RT program died versus 63 (53.8%) patients of the control group (P = 0.063).

CONCLUSIONS

The 12-month GET-RT program was associated with an improved fitness during 1-yr follow-up, whereas a tendency toward better survival rates was observed during long-term follow-up.

Predictors of Exercise Training and Physical Activity Adherence in People Recently Hospitalized With Heart Failure: A BRIEF REPORT

PURPOSE

For individuals with heart failure (HF), frequent attendance at exercise training programs and meeting physical activity (PA) guidelines are significantly associated with improvements in 6-min walk distance. Despite the evidence, adherence to exercise interventions remains poor. The aim of this study was to identify predictors of these 2 variables in patients recently hospitalized with HF.

METHODS

In this substudy of the Exercise Joins Education: Combined Therapy to Improve Outcomes in Newly-discharged Heart Failure (EJECTION-HF) trial, all participants were enrolled in a HF disease management program, including weekly review of a home exercise program for 12 wk. Intervention group participants additionally undertook twice weekly supervised exercise training. Primary outcomes were frequent exercise training program attendance (≥12 sessions) and attainment of PA guidelines (150 min/wk of moderate intensity exercise) at 12 wk. Participant and clinical characteristics were analyzed using a logistic regression model to identify significant predictors of each outcome.

RESULTS

A total of 278 participants provided PA data and 140 contributed attendance data. New diagnosis of HF was a significant predictor of frequent program attendance (OR = 2.3; 95% CI, 1.1-4.7; P = .03). Predictors of meeting PA guidelines at follow-up included new HF diagnosis (OR = 2.4; 95% CI, 1.2-4.8, P = .013), and being physically active at baseline (OR = 2.7; 95% CI, 1.3-5.6; P = .007). Gender, symptom severity, multimorbidity, and disability were not significantly associated with either outcome in multivariate analysis.

CONCLUSION

To improve adherence, specific strategies may be required for patients with decompensated HF and those physically inactive at time of referral.

Benefits and Risks of High-Intensity Interval Training in Patients With Coronary Artery Disease

Exercise-based cardiac rehabilitation is integral to secondary prevention in patients with coronary artery disease. Recently, the effectiveness and "superiority" of high-intensity interval training (HIIT) is a purported time-saving alternative to "traditional" moderate-intensity continuous training (MICT) in cardiac rehabilitation. The rationale for HIIT adoption is, however, not fully substantiated in the scientific literature. Established guidelines for exercise testing and training, when carefully adhered to, reduce the likelihood of triggering a cardiac event or inducing musculoskeletal injury. Clinicians should likewise consider patient risk stratification and introduce HIIT as an alternative to MICT only after patients exhibit stable and asymptomatic responses to vigorous exercise training. Although HIIT adherence appears comparable with MICT during outpatient rehabilitation, compliance drops dramatically for unsupervised exercise. Despite the enthusiasm surrounding HIIT, its main advantage over MICT appears to be short-term exercise performance outcomes and indices of vascular function. Regarding benefits to cardiovascular disease risk factor modification, management of vital signs, and measures of cardiac performance, current evidence indicates that HIIT does not outperform MICT. Long-term outcomes to HIIT are currently uncertain and logistical constraints to HIIT incorporation need additional clarification. Based on these limited findings, derived from facilities and clinicians at the forefront of cardiac rehabilitation, the routine adoption of HIIT should be viewed cautiously. In conclusion, the current review highlights numerous specific research directives that are needed before the safety and effectiveness of HIIT can be confirmed and widely adopted in patients with known or suspected coronary artery disease, especially in unsupervised, nonmedical settings.

Exercise-based cardiac rehabilitation for adults with heart failure

BACKGROUND

Chronic heart failure (HF) is a growing global health challenge. People with HF experience substantial burden that includes low exercise tolerance, poor health-related quality of life (HRQoL), increased risk of mortality and hospital admission, and high healthcare costs. The previous (2014) Cochrane systematic review reported that exercise-based cardiac rehabilitation (CR) compared to no exercise control shows improvement in HRQoL and hospital admission among people with HF, as well as possible reduction in mortality over the longer term, and that these reductions appear to be consistent across patient and programme characteristics. Limitations noted by the authors of this previous Cochrane Review include the following: (1) most trials were undertaken in patients with HF with reduced (< 45%) ejection fraction (HFrEF), and women, older people, and those with preserved (≥ 45%) ejection fraction HF (HFpEF) were under-represented; and (2) most trials were undertaken in the hospital/centre-based setting.

OBJECTIVES

To determine the effects of exercise-based cardiac rehabilitation on mortality, hospital admission, and health-related quality of life of people with heart failure.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and three other databases on 29 January 2018. We also checked the bibliographies of systematic reviews and two trial registers.

SELECTION CRITERIA

We included randomised controlled trials that compared exercise-based CR interventions with six months' or longer follow-up versus a no exercise control that could include usual medical care. The study population comprised adults (> 18 years) with evidence of HF - either HFrEF or HFpEF.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened all identified references and rejected those that were clearly ineligible for inclusion in the review. We obtained full papers of potentially relevant trials. Two review authors independently extracted data from the included trials, assessed their risk of bias, and performed GRADE analyses.

MAIN RESULTS

We included 44 trials (5783 participants with HF) with a median of six months' follow-up. For this latest update, we identified 11 new trials (N = 1040), in addition to the previously identified 33 trials. Although the evidence base includes predominantly patients with HFrEF with New York Heart Association classes II and III receiving centre-based exercise-based CR programmes, a growing body of studies include patients with HFpEF and are undertaken in a home-based setting. All included studies included a no formal exercise training intervention comparator. However, a wide range of comparators were seen across studies that included active intervention (i.e. education, psychological intervention) or usual medical care alone. The overall risk of bias of included trials was low or unclear, and we downgraded results using the GRADE tool for all but one outcome.Cardiac rehabilitation may make little or no difference in all-cause mortality over the short term (≤ one year of follow-up) (27 trials, 28 comparisons (2596 participants): intervention 67/1302 (5.1%) vs control 75/1294 (5.8%); risk ratio (RR) 0.89, 95% confidence interval (CI) 0.66 to 1.21; low-quality GRADE evidence) but may improve all-cause mortality in the long term (> 12 months follow up) (6 trials/comparisons (2845 participants): intervention 244/1418 (17.2%) vs control 280/1427 (19.6%) events): RR 0.88, 95% CI 0.75 to 1.02; high-quality evidence). Researchers provided no data on deaths due to HF. CR probably reduces overall hospital admissions in the short term (up to one year of follow-up) (21 trials, 21 comparisons (2182 participants): (intervention 180/1093 (16.5%) vs control 258/1089 (23.7%); RR 0.70, 95% CI 0.60 to 0.83; moderate-quality evidence, number needed to treat: 14) and may reduce HF-specific hospitalisation (14 trials, 15 comparisons (1114 participants): (intervention 40/562 (7.1%) vs control 61/552 (11.1%) RR 0.59, 95% CI 0.42 to 0.84; low-quality evidence, number needed to treat: 25). After CR, a clinically important improvement in short-term disease-specific health-related quality of life may be evident (Minnesota Living With Heart Failure questionnaire - 17 trials, 18 comparisons (1995 participants): mean difference (MD) -7.11 points, 95% CI -10.49 to -3.73; low-quality evidence). Pooling across all studies, regardless of the HRQoL measure used, shows there may be clinically important improvement with exercise (26 trials, 29 comparisons (3833 participants); standardised mean difference (SMD) -0.60, 95% CI -0.82 to -0.39; I² = 87%; Chi² = 215.03; low-quality evidence). ExCR effects appeared to be consistent different models of ExCR delivery: centre vs. home-based, exercise dose, exercise only vs. comprehensive programmes, and aerobic training alone vs aerobic plus resistance programmes.

AUTHORS' CONCLUSIONS

This updated Cochrane Review provides additional randomised evidence (11 trials) to support the conclusions of the previous version (2014) of this Cochane Review. Compared to no exercise control, CR appears to have no impact on mortality in the short term (< 12 months' follow-up). Low- to moderate-quality evidence shows that CR probably reduces the risk of all-cause hospital admissions and may reduce HF-specific hospital admissions in the short term (up to 12 months). CR may confer a clinically important improvement in health-related quality of life, although we remain uncertain about this because the evidence is of low quality. Future ExCR trials need to continue to consider the recruitment of traditionally less represented HF patient groups including older, female, and HFpEF patients, and alternative CR delivery settings including home- and using technology-based programmes.

Cardioprotective effects of physical exercise on redox biology in mice exposed to hand-rolled cornhusk cigarette smoke

The present study sought to evaluate the effects of physical training on histological parameters and oxidative stress in the myocardium of mice chronically exposed to hand-rolled cornhusk cigarette (HRCC) smoke. Male Swiss mice (60 days old, 30-35 g) were either exposed to ambient air or passively exposed to the smoke of 12 cigarettes daily over 3 sessions (4 cigarettes per session) for 60 consecutive days with or without physical training for 8 weeks. Forty-eight hours after the last training session, the heart was surgically removed for histological analysis and measurement of oxidative stress parameters. Histological imaging revealed cell disruption, with poorly defined nuclei, in the mice exposed to HRCC smoke, but not in the control group. However, mice exposed to HRCC smoke with physical training displayed signs of tissue repair and improved tissue integrity. Biochemical analysis revealed decreased production of superoxide, 2',7'-dichlorofluorescein (DCF), and nitrite, as well as decreased protein carbonylation, in the physical training groups, likely due to the exercise-induced increase in glutathione peroxidase (GPX) activity and glutathione (GSH) content. Taken together, our results suggest that physical exercise exerts cardioprotective effects by modulating the redox responses in animals exposed to HRCC smoke.

Reported methods for handling missing change standard deviations in meta-analyses of exercise therapy interventions in patients with heart failure: A systematic review

Background

Well-constructed systematic reviews and meta-analyses are key tools in evidenced-based healthcare. However, a common problem with performing a meta-analysis is missing data, such as standard deviations (SD). An increasing number of methods are utilised to calculate or impute missing SDs, allowing these studies to be included in analyses. The aim of this review was to investigate the methods reported and utilised for handling missing change SDs in meta-analyses, using the topic of exercise therapy in heart failure patients as a model.

Methods

A systematic search of PubMed, EMBASE and Cochrane Library from 1 January 2014 to 31st March 2018 was conducted for meta-analyses of exercise based trials in heart failure. Studies were eligible to be included if they performed a meta-analysis of change in exercise capacity in heart failure patients after a training intervention.

Results

Twenty two publications performed a meta-analysis on the effect of exercise therapy on exercise capacity in heart failure patients. Eleven (50%) publications did not directly report the approach for dealing with missing change SDs. Approaches reported and utilised to deal with missing change SDs included imputation, actual and approximate algebraic recalculation using study level summary statistics and exclusion of studies.

Conclusion

Change SDs are often not reported in trial papers and while in the first instance meta-analysts should attempt to obtain missing data from trial authors, this information is frequently not forthcoming. Meta-analysts are then forced to make a decision on how these trials and missing data are to be handled. Whilst not one approach is favoured for dealing with this matter, authors need to clearly report the approach to be utilised for missing change SDs. Where change SDs are imputed meta-analyst are encouraged to explore several options and have a sound rationale as to the choice, and where data is imputed, sensitivity analysis should be conducted.

Exercise-based cardiac rehabilitation for people with implantable ventricular assist devices

BACKGROUND

Heart failure is the end stage of heart disease, and the prevalence and incidence of the condition is rapidly increasing. Although heart transplantation is one type of surgical treatment for people with end-stage heart failure, donor availability is limited. Implantable ventricular assist devices (VADs) therefore offer an alternative treatment to heart transplantation. Although two studies reported the beneficial effects of exercise-based cardiac rehabilitation (CR) on functional capacity and quality of life (QOL) by performing systematic reviews and meta-analyses, both systematic reviews included studies with limited design (e.g. non-randomised, retrospective studies) or participants with implantable or extracorporeal VADs.

OBJECTIVES

To determine the benefits and harms of exercise-based CR for people with implantable VADs.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE, Embase, PsycINFO, Conference Proceedings Citation Index-Science (CPCI-S) on Web of Science, CINAHL, and LILACS on 3 October 2017 with no limitations on date, language, or publication status. We also searched two clinical trials registers on 10 August 2017 and checked the reference lists of primary studies and review articles.

SELECTION CRITERIA

Randomised controlled trials (RCTs) regardless of cluster or individual randomisation, and full-text studies, those published as abstract only, and unpublished data were eligible. However, only individually RCTs and full-text publications were included.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted outcome data from the included studies. We double-checked that data were entered correctly by comparing the data presented in the systematic review with the study reports. We had no dichotomous data to analyse and used mean difference or standardised mean difference with 95% confidence intervals (CIs) for continuous data. Furthermore, we assessed the quality of evidence as it relates to those studies that contribute data to the meta-analyses for the prespecified outcomes, using GRADEpro software.

MAIN RESULTS

We included two studies with a total of 40 participants in the review. Exercise-based CR consisted of aerobic or resistance training or both three times per week for six to eight weeks. Exercise intensity was 50% of oxygen consumption (VO2) reserve, or ranged from 60% to 80% of heart rate reserve. Two serious adverse events were observed in one trial, in which participants did not complete the study due to infections. Furthermore, a total of four participants in each group required visits to the emergency department, although these participants did complete the study. Summary scores from the 36-item Short Form Health Survey (SF-36) and the Kansas City Cardiomyopathy Questionnaire (KCCQ) were measured as quality of life. One trial reported that the KCCQ summary score improved by 14.4 points in the exercise group compared with 0.5 points in the usual care group. The other trial reported that the SF-36 total score improved by 29.2 points in the exercise group compared with 16.3 points in the usual care group. A large difference in quality of life was observed between groups at the end of follow-up (standardised mean difference 0.88, 95% CI -0.12 to 1.88; 37 participants; 2 studies; very low-quality of evidence). However, there was no evidence for the effectiveness of exercise-based CR due to the young age of the participants, high risk of performance bias, very small sample size, and wide confidence intervals, which resulted in very low-quality evidence. Furthermore, we were not able to determine the effect of exercise-based CR on mortality, rehospitalisation, heart transplantation, and cost, as these outcomes were not reported.

AUTHORS' CONCLUSIONS

The evidence is currently inadequate to assess the safety and efficacy of exercise-based CR for people with implantable VADs compared with usual care. The amount of RCT evidence was very limited and of very low quality. In addition, the training duration was very short term, that is from six to eight weeks. Further high-quality and well-reported RCTs of exercise-based CR for people with implantable VADs are needed. Such trials need to collect data on events (mortality and rehospitalisation), patient-related outcomes (including quality of life), and cost-effectiveness.

What is the effect of aerobic exercise intensity on cardiorespiratory fitness in those undergoing cardiac rehabilitation? A systematic review with meta-analysis

OBJECTIVE

Assess the role of exercise intensity on changes in cardiorespiratory fitness (CRF) in patients with cardiac conditions attending exercise-based cardiac rehabilitation.

DESIGN

Systematic review with meta-analysis.

DATA SOURCES

MEDLINE, Embase, CINAHL, SPORTDiscus, PsycINFO and Web of Science.

ELIGIBILITY CRITERIA FOR SELECTION

Studies assessing change in CRF (reported as peak oxygen uptake; V̇O_2peak) in patients post myocardial infarction and revascularisation, following exercise-based cardiac rehabilitation. Studies establishing V̇O_2peak via symptom-limited exercise test with ventilatory gas analysis and reported intensity of exercise during rehabilitation were included. Studies with mean ejection fraction <40% were excluded.

RESULTS

128 studies including 13 220 patients were included. Interventions were classified as moderate, moderate-to-vigorous or vigorous intensity based on published recommendations. Moderate and moderate-to-vigorous-intensity interventions were associated with a moderate increase in relative V̇O_2peak (standardised mean difference±95% CI=0.94±0.30 and 0.93±0.17, respectively), and vigorous-intensity exercise with a large increase (1.10±0.25). Moderate and vigorous-intensity interventions were associated with moderate improvements in absoluteV̇O_2peak (0.63±0.34 and 0.93±0.20, respectively), whereas moderate-to-vigorous-intensity interventions elicited a large effect (1.27±0.75). Large heterogeneity among studies was observed for all analyses. Subgroup analyses yielded statistically significant, but inconsistent, improvements in CRF.

CONCLUSION

Engagement in exercise-based cardiac rehabilitation was associated with significant improvements in both absolute and relative V̇O_2peak. Although exercise of vigorous intensity produced the greatest pooled effect for change in relative V̇O_2peak, differences in pooled effects between intensities could not be considered clinically meaningful.

REGISTRATION

Prospero CRD42016035638.

Exercise for Preventing Hospitalization and Readmission in Adults With Congestive Heart Failure

We critically appraised all available evidence regarding exercise interventions for improving patient survival and reducing hospital admissions in adults with chronic heart failure (HF). We searched 4 databases up to April 2018 and graded the quality of evidence according to the Grading of Recommendations Assessment, Development and Evaluation working group approach. We reviewed 7 meta-analyses and the publications of 48 randomized controlled trials (RCTs). In HF with reduced ejection fraction, low-quality evidence suggests that exercise prevents all-cause hospitalizations [Relative risk (RR), 0.77; 95% confidence interval (CI), 0.63 to 0.93; 1328 patients in 15 RCTs] and hospitalizations due to HF (RR, 0.57; 95% CI, 0.37 to 0.88; 1073 patients in 13 RCTs) and improves quality of life (standardized mean difference, -0.37; 95% CI, -0.60 to -0.14; 1270 patients in 25 RCTs) but has no effect on mortality. In HF with preserved ejection fraction, low-quality evidence suggests that exercise improves peak oxygen uptake (mean difference, 2.36; 95% CI, 1.16 to 3.57; 171 patients in 3 RCTs) and quality of life (mean difference, -4.65; 95% CI, -8.46 to -0.83; 203 patients in 4 RCTs). In patients after heart transplantation, low-quality evidence suggests that exercise improves peak oxygen uptake (standardized mean difference, 0.68; 95% CI, 0.43 to 0.93; 284 patients in 9 RCTs) but does not improve quality of life. In order to reduce hospitalization and improve quality of life for adults with HF and reduced ejection fraction, clinicians should recommend exercise interventions. For adults with HF and preserved ejection fraction and in those undergoing heart transplantation, clinicians may recommend exercise interventions in order to improve peak oxygen uptake.

Exercise and heart failure: an update

The present update is dedicated to the evolution of the interaction between heart failure (HF) and exercise and how the scientific community has handled it. Indeed, on the one hand, HF is a leading cause of morbidity and mortality with a stable prevalence from 1998 onward varying between 6.3% and 13.3%. On the other hand, exercise is seen as a diagnostic and prognostic tool as well as a therapeutic intervention in chronic HF. More precisely, the knowledge, the clinical application, and the research interest on the mutual interactions between exercise and HF have different phases in disease progression: Before HF onset (past): exercise provides protective benefit in preventing HF (primary prevention). With HF present: exercise improvement with training provides benefits in HF (secondary prevention). The prediction of future in HF patients: exercise impairment, as a leading characteristic of HF, is used as a prognostic factor.

High intensity interval training versus moderate intensity continuous training on exercise capacity and quality of life in patients with heart failure with reduced ejection fraction: A systematic review and meta-analysis

OBJECTIVE

The aim of this study was to investigate the effects of high intensity interval training (HIIT) versus moderate intensity continuous training (MICT) in heart failure patients with reduced ejection fraction (HFrEF).

BACKGROUND

Despite the well-known positive effects of exercise in heart failure patients, the best mode of exercise is still under discussion.

METHODS

We searched Pubmed/MEDLINE, Cochrane Central Register of Controlled Trials, PEDro data base, and SciELO (from the earliest date available to October 2017) for randomized controlled trials that evaluated the effects of HIIT versus MICT in HFrEF patients. Weighted mean differences (WMD) with 95% confidence interval (CI) were calculated, and heterogeneity was assessed using the I² test.

RESULTS

13 studies met the study criteria, including 411 patients. Compared to MICT, HIIT resulted in improvement in Peak VO₂ WMD (1.35 mL·kg^-1·min^-1 95% CI: 0.03 to 2.64 N = 411). HIIT resulted in no difference in VE/VCO₂ slope WMD (-1.21 95% CI: -3.0 to 0.58 N = 135), and quality of life measured by Minnesota Living with Heart Failure questionnaire WMD (1.19 95% CI: -5.81 to 8.19 N = 79). Sub-group analyses comparing studies with and without isocaloric exercise training protocol also showed a nonsignificant difference in peak VO₂ for participants in the HIIT group compared with MICT group.

CONCLUSIONS

HIIT improves peak VO₂ and should be considered as a component of care of HFrEF patients. However, its superiority versus MICT disappears when isocaloric protocols are compared. An important caveat is uncertainty and variation of actual training intensities compared to program targets.

Effects of l-arginine supplementation associated with continuous or interval aerobic training on chronic heart failure rats

OBJECTIVE

Chronic heart failure (CHF) is related with exercise intolerance and impaired nitric oxide (NO) production, which can lead to several functional capacity alterations. Considering the possible superiority of aerobic interval training compared to continuous training and the capacity of l-arginine to restore the NO pathway, the aim of the present study was to investigate whether these treatments are beneficial to exercise capacity, muscle mass preservation and hemodynamic, inflammatory and oxidative stress parameters in CHF rats.

METHODS

Thirty-eight male Wistar rats post 6weeks of myocardial infarction (MI) surgery were randomly assigned into 6 CHF groups: sedentary (SED, n=6); SED+Arg (n=7); ACT (n=8); ACT+Arg (n=5); AIT (n=7); AIT+Arg (n=5). Exercise test capacity (ETC) was performed pre and post 8weeks of intervention. Supplemented rats received Arg (1g/kg) by oral gavage (7×/week). Exercise training was performed on a rat treadmill (5×/week). Hemodynamic variables, tissue collection, congestion, inflammatory cytokines, and oxidative parameters were evaluated at the end of protocols.

RESULTS

All trained groups showed a superior exercise capacity compared to SED groups on the post-intervention test (p<0.0001). Pulmonary congestion was attenuated in AIT and AIT+Arg compared with the SED group (p<0.05). Left ventricular end-diastolic pressure (LVEDP) was lower in ACT+Arg, AIT, and AIT+Arg groups than SED group (p<0.05). Association of AIT with Arg supplementation was able to improve hemodynamic responses (left ventricular systolic pressure (LVSP), systolic blood pressure (SBP), +dP/dt_max, and -dP/dt_max (p<0.05), likewise, decrease muscular and renal lipid peroxidation and tumor necrosis factor (TNF)-α, and increase interleukin (IL)-10/TNF-α plasmatic levels (p<0.01). Groups that associated aerobic exercise with Arg supplementation (ACT+Arg and AIT+Arg) revealed higher gastrocnemius mass compared to the SED group (p<0.01).

CONCLUSIONS

Both aerobic training protocols were capable to improve aerobic capacity, and the association with Arg supplementation was important to attenuate muscle loss. Moreover, interval training associated with Arg supplementation elicits greater improvements in hemodynamic parameters, contributing to reduction in pulmonary congestion, and demonstrated particular responses in the inflammatory profile and in the antioxidant status.

High-intensity interval training versus moderate-intensity continuous training on exercise capacity and quality of life in patients with coronary artery disease: A systematic review and meta-analysis

Background Exercise is an effective strategy for reducing total and cardiovascular mortality in patients with coronary artery disease. However, it is not clear which modality is best. We performed a meta-analysis to investigate the effects of high-intensity interval versus moderate-intensity continuous training of coronary artery disease patients. Methods We searched MEDLINE, PEDro, LILACS, SciELO and the Cochrane Library (from the earliest date available to November 2016) for controlled trials that evaluated the effects of high-intensity interval versus moderate-intensity continuous training for coronary artery disease patients. Weighted mean differences and 95% confidence intervals were calculated, and heterogeneity was assessed using the I² test. Results Twelve studies met the study criteria, including 609 patients. High-intensity interval training resulted in improvement in peak oxygen uptake weighted mean difference (1.3 ml/kg/min, 95% confidence interval: 0.6-1.9, n = 594) compared with moderate-intensity continuous training. No significant difference in physical, emotional, and social domain of quality of life was found for participants for participants in the high-intensity interval training group compared with the moderate-intensity continuous training group. Sub-analysis of three studies with isocaloric exercise training showed no significant difference in peak oxygen uptake weighted mean difference (0.4 ml/kg/min, 95% confidence interval: -0.1-0.9, n = 137) for participants in the high-intensity interval training group compared with moderate-intensity continuous training group. Conclusions High-intensity interval training may improve peak oxygen uptake and should be considered as a component of care of coronary artery disease patients. However, this superiority disappeared when isocaloric protocol is compared.

The influence of training characteristics on the effect of exercise training in patients with coronary artery disease: Systematic review and meta-regression analysis

BACKGROUND

Although exercise-based cardiac rehabilitation improves exercise capacity of coronary artery disease patients, it is unclear which training characteristic determines this improvement. Total energy expenditure and its constituent training characteristics (training intensity, session frequency, session duration and programme length) vary considerably among clinical trials, making it hard to compare studies directly. Therefore, we performed a systematic review and meta-regression analysis to assess the effect of total energy expenditure and its constituent training characteristics on exercise capacity.

METHODS

We identified randomised controlled trials comparing continuous aerobic exercise training with usual care for patients with coronary artery disease. Studies were included when training intensity, session frequency, session duration and programme length was described, and exercise capacity was reported in peakVO₂. Energy expenditure was calculated from the four training characteristics. The effect of training characteristics on exercise capacity was determined using mixed effects linear regression analyses. The analyses were performed with and without total energy expenditure as covariate.

RESULTS

Twenty studies were included in the analyses. The mean difference in peakVO₂ between the intervention group and control group was 3.97ml·min^-1·kg^-1 (p<0.01, 95% CI 2.86 to 5.07). Total energy expenditure was significantly related to improvement of exercise capacity (effect size 0.91ml·min^-1·kg^-1 per 100J·kg, p<0.01, 95% CI 0.77 to 1.06), no effect was found for its constituent training characteristics after adjustment for total energy expenditure.

CONCLUSIONS

We conclude that the design of an exercise programme should primarily be aimed at optimising total energy expenditure rather than on one specific training characteristic.

Molecular effects of exercise training in patients with cardiovascular disease: focus on skeletal muscle, endothelium, and myocardium

For decades, we have known that exercise training exerts beneficial effects on the human body, and clear evidence is available that a higher fitness level is associated with a lower incidence of suffering premature cardiovascular death. Despite this knowledge, it took some time to also incorporate physical exercise training into the treatment plan for patients with cardiovascular disease (CVD). In recent years, in addition to continuous exercise training, further training modalities such as high-intensity interval training and pyramid training have been introduced for coronary artery disease patients. The beneficial effect for patients with CVD is clearly documented, and during the last years, we have also started to understand the molecular mechanisms occurring in the skeletal muscle (limb muscle and diaphragm) and endothelium, two systems contributing to exercise intolerance in these patients. In the present review, we describe the effects of the different training modalities in CVD and summarize the molecular effects mainly in the skeletal muscle and cardiovascular system.