Greater improvement in cardiorespiratory fitness using higher-intensity interval training in the standard cardiac rehabilitation setting. J Cardiopulm Rehabil Prev. 2014;34:98-105. [PMID: 24531203 DOI: 10.1097/hcr.0000000000000049]

Volume of Aerobic Exercise to Optimize Outcomes in Cardiac Rehabilitation: An Official Statement From the American Association of Cardiovascular and Pulmonary Rehabilitation

Exercise training is a core component of cardiac rehabilitation (CR) programming. Exercise and, more broadly, physical activity are critical elements to secondary prevention of cardiovascular disease. The central components of the exercise prescription are well-defined and include frequency (how many bouts of exercise per week), intensity (how hard to exercise), time (duration of exercise session), type (modality of exercise), and progression (rate of increase in the dose of exercise). Specific targets for the volume (total amount) of exercise, however, are less well-defined. This Position Statement provides a general overview of the specific goals for the volume of aerobic exercise to optimize long-term outcomes for participants in CR. Additionally, examples are provided to illustrate how to integrate the various aspects of the exercise.

Endurance Training Exercise Dose in Coronary Artery Disease Rehabilitation

Clinical management of patients with atherosclerotic coronary artery disease (CAD) following acute coronary syndrome includes cardiac rehabilitation. The well-established hallmark of cardiac rehabilitation is structured aerobic exercise training. To date, however, a limited number of studies have directly compared the effects of different doses of exercise on cardiovascular health, leaving uncertainty about the possible differential benefits of different exercise doses for use during cardiac rehabilitation. To address this area of uncertainty, we conducted a literature review and comparative analyses of studies that both compared two or more exercise interventions and assessed pre- and post-intervention peak oxygen consumption (V˙O2PEAK). Results from these analyses suggest that high exercise intensity, even when performed over relatively short duration interventions, appears to yield the most substantial improvements in cardiorespiratory fitness. However, this conclusion is based on the limited number of available studies, underscoring the need for future work examining exercise dose and clinical outcomes in the cardiac rehabilitation setting.

Effects of high-intensity interval training on physical morphology, cardiopulmonary function, and metabolic indicators in older adults: a systematic review and meta-analysis

Background

Despite the growing attention towards the efficacy of high-intensity interval training (HIIT) on older adult health, a consensus regarding the pleiotropic effects of HIIT in this population is yet to be reached. Previous studies have predominantly focused on specific outcomes or particular groups, lacking comprehensive analysis.

Objective

We aimed to conduct a systematic evaluation of the impact of HIIT on body composition, cardiopulmonary function, and metabolic parameters in older adults.

Methods

The databases searched included PubMed, Web of Science, Cochrane Library, Scopus, WanFang, and other relevant sources from the inception of the database until July 2023. Randomized controlled trials (RCTs) on the effects of HIIT on body shape, cardiopulmonary function, and metabolic parameters in the older adult were searched.

Results

A total of 87 RCTs meeting the criteria were included, involving 4,213 older adult people. Meta-analysis results showed that HIIT significantly improved body fat percentage (BF%) [MD: -1.63%, p = 0.005], maximal oxygen uptake (VO2max) [MD: 2.46 mL min-1 kg-1, p < 0.00001], maximal heart rate (HRmax) [MD: 2.83 beats min-1, p = 0.02], and high-density lipoprotein (HDL) levels [MD: 0.04 mmol L-1, p = 0.002]. However, for systolic blood pressure (SBP) [MD: 0.49 mmHg, p = 0.60], resting heart rate (HRrest) [MD: -0.95 BPM -1, p = 0.24], triglycerides (TG) [tendency for MD: -0.02 mmol L-1, p = 0.61], low-density lipoprotein (LDL) [MD: -0.04 mmol L-1, p = 0.27] had no significant effect. Sensitivity analysis found that HIIT significantly improved waist circumference (WC) [MD: -1.89 cm, p = 0.17], diastolic blood pressure (DBP) [MD: -0.63 mmHg, p = 0.23], respiratory exchange rate (RER) [MD: 0.01, p = 0.20], total cholesterol (TC) [MD: 0.10 mmol L-1, p = 0.14], and fasting plasma glucose (FPG) [MD:-0.20 mmol L-1, p = 0.08], but the results lacked robustness. There was no significant improvement in DBP [MD: -0.63 mmHg, p = 0.23] and body mass index (BMI) [MD: -0.36 kg m-2, p = 0.06].

Conclusions

HIIT has shown certain potential and advantages in improving the physical health of the older adult, especially in cardiopulmonary function. However, more high-quality studies are needed to confirm the effects of HIIT on the physical health of the older adult in the future. It also provides a reference for the clinical practice and family health management of HIIT in the older adult and the development of HIIT guidelines.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/myprospero, identifier CRD42023460252.

Impact of exercise training on exercise tolerance, cardiac function and quality of life in individuals with heart failure and preserved ejection fraction: a systematic review and meta-analysis

BACKGROUND

Heart failure with preserved ejection fraction (HFpEF) is increasingly prevalent and poses significant treatment challenges due to its complex pathophysiology. Exercise training has emerged as a promising non-pharmacological intervention to improve outcomes in HFpEF patients. This study aims to evaluate the effect of exercise training on exercise tolerance, cardiac function and quality of life in HFpEF patients.

METHOD

Through systematic review and meta-analysis, major databases were scoured for randomized controlled trials (RCTs) evaluating the influence of exercise training on HFpEF patients. Data on exercise tolerance, cardiac function parameters, and quality of life were extracted. The quality of the studies was assessed using the Cochrane Collaboration's risk of bias tool. Statistical analyses were performed using Review Manager 5.4, with mean differences (MD) or standardized mean differences (SMD) and 95% confidence intervals (CIs) calculated for continuous variables.

RESULTS

Seven RCTs encompassing 470 participants met the inclusion criteria. Exercise training significantly improved exercise tolerance as measured by the 6-Minute Walk Test (P < 0.01) and peak VO₂ (P = 0.03). No significant effects were observed on cardiac function parameters, including the E/A ratio, E/e' ratio, and LVEF. Total quality of life was similar between exercise and control groups, but significantly enhanced in physical components about quality of life was observed in the exercise group (P = 0.03). There were no significant differences between high-intensity interval training (HIIT) and moderate continuous training (MCT) in improving exercise tolerance, cardiac function, or quality of life.

CONCLUSION

Exercise training effectively enhances exercise tolerance and physical quality of life in patients with HFpEF, without significantly impacting cardiac function parameters. HIIT and MCT has similar effect in HFpEF patients. These findings support the incorporation of exercise training into the management strategies for HFpEF patients to improve functional outcomes and quality of life.

Effectiveness of exercise-based cardiac rehabilitation for patients with left ventricular assist device: A systematic review and meta-analysis

PURPOSE

Exercise-based cardiac rehabilitation (EBCR) improves functional capacity in heart failure (HF). However, data on the effect of EBCR in patients with advanced HF and left ventricular assist devices (LVADs) are limited. This meta-analysis aimed to evaluate the impact of EBCR on the functional ability of LVAD patients by comparing the corresponding outcome indicators between the EBCR and ST groups.

METHODS

PubMed, Embase, Clinical Trials, and Cochrane Library databases were searched for studies assessing and comparing the effects of EBCR and standard therapy (ST) in patients following LVAD implantation. Using pre-defined criteria, appropriate studies were identified and selected. Data from selected studies were extracted in a standardized fashion, and a meta-analysis was performed using a fixed-effects model. The protocol was registered on INPLASY (202340073).

RESULTS

In total, 12 trials involving 477 patients were identified. The mean age of the participants was 52.9 years, and 78.6% were male. The initiation of EBCR varied from LVAD implantation during the index hospitalization to 11 months post-LVAD implantation. The median rehabilitation period ranged from 2 weeks to 18 months. EBCR was associated with improved peak oxygen uptake (VO2) in all trials. Quantitative analysis was performed in six randomized studies involving 214 patients (EBCR: n = 130, ST: n = 84). EBCR was associated with a significantly high peak VO2 (weighted mean difference [WMD] = 1.64 mL/kg/min; 95% confidence interval [CI], 0.20-3.08; p = .03). Similarly, 6-min walk distance (6MWD) showed significantly greater improvement in the EBCR group than in the ST group (WMD = 34.54 m; 95% CI, 12.47-56.42; p = .002) in 266 patients (EBCR, n = 140; ST, n = 126). Heterogeneity was low among the included trials. None of the included studies reported serious adverse events related to EBCR, indicating the safety of EBCR after LVAD implantation.

CONCLUSION

This study demonstrated that EBCR following LVAD implantation is associated with greater improvement in functional capacity compared with ST as reflected by the improved peak VO2 and 6MWD values. Considering the small number of patients in this analysis, further research on the clinical impact of EBCR in LVAD patients is warranted.

Core Components of Cardiac Rehabilitation Programs: 2024 Update: A Scientific Statement From the American Heart Association and the American Association of Cardiovascular and Pulmonary Rehabilitation: Endorsed by the American College of Cardiology

The science of cardiac rehabilitation and the secondary prevention of cardiovascular disease has progressed substantially since the most recent American Heart Association and American Association of Cardiovascular and Pulmonary Rehabilitation update on the core components of cardiac rehabilitation and secondary prevention programs was published in 2007. In addition, the advent of new care models, including virtual and remote delivery of cardiac rehabilitation services, has expanded the ways that cardiac rehabilitation programs can reach patients. In this scientific statement, we update the scientific basis of the core components of patient assessment, nutritional counseling, weight management and body composition, cardiovascular disease and risk factor management, psychosocial management, aerobic exercise training, strength training, and physical activity counseling. In addition, in recognition that high-quality cardiac rehabilitation programs regularly monitor their processes and outcomes and engage in an ongoing process of quality improvement, we introduce a new core component of program quality. High-quality program performance will be essential to improve widely documented low enrollment and adherence rates and reduce health disparities in cardiac rehabilitation access.

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

BACKGROUND

With the increasing utilization of cardiac rehabilitation in clinical treatment and prognosis for patients with cardiovascular diseases, exercise training has become a crucial component. High-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) are commonly employed in rehabilitating patients with cardiovascular diseases. However, further investigation is required to determine whether HIIT and MICT can effectively enhance the prognosis of patients with coronary artery disease. Therefore, this study aims to assess the effectiveness of HIIT and MICT interventions, optimal intervention duration for different intensity levels of training, as well as effective training modalities that improve cardiorespiratory function and exercise capacity among patients.

METHODS

We conducted a comprehensive search of the Cochrane Library, PubMed, EMbase, Web of Science, and CINAHL databases for randomized controlled trials (RCTs) pertaining to high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) interventions in patients with coronary artery disease from inception until publication on September 26, 2024. Two independent researchers assessed articles that met the inclusion criteria and analyzed the results using Sata 17.0 software. Forest plots were employed to evaluate the impact of HIIT and MICT on outcome indicators. Sensitivity analysis and funnel plot assessment were performed to examine publication bias. Subgroup analysis was conducted to determine optimal intervention duration and training methods.

RESULTS

A total of 22 studies with 1364 patients were included in the study, including the HIIT group (n = 685) and the MICT group (n = 679). The results showed that compared to MICT, HIIT significantly increased PeakVO2(Peak oxygen uptake)[WMD = 1.42mL /kg/min 95%CI (0.87, 1.98), P = 0.870, I2 = 0%], 6MWT(6-minute walk test)[WMD = 18.60m 95%CI (2.29, 34.92), P = 0.789, I2 = 0%], PHR(Peak heart rate)[WMD = 4.21bpm 95%CI (1.07, 7.36), P = 0.865, I2 = 0%], DBP(diastolic blood pressure)[WMD = 3.43mmHg 95%CI (1.09, 5.76), P = 0.004, I2 = 60.2%]. However, in LVEF(left- ventricular ejection fraction)[WMD = 0.32mL 95%CI (-1.83, 2.46), P = 0.699, I2 = 0%], LVEDV(left ventricular end-diastolic volume)[WMD = 0.91 ml 95%CI (-1.83, 2.46), P = 0.995, I2 = 0%] and SBP(systolic blood pressure)[WMD = 1.85mmHg 95%CI (-0.23, 3.93),P = 0.266, I2 = 18.2%], there was no significant difference between HIIT and MICT.

CONCLUSION

Based on the findings of this systematic review, HIIT demonstrates superior efficacy compared to MICT in enhancing PeakVO2, PHR, 6MWT and DBP. However, no significant differences were observed in LVEF, LVEDV, and SBP. In summary, HIIT exhibits potential for improving cardiopulmonary function and exercise capacity among patients with coronary artery disease.

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

BACKGROUND

Despite the well-known positive effects of exercise in patients with coronary artery disease, the best exercise training protocol is still under discussion.

OBJECTIVE

We performed a systematic review and a meta-analysis to investigate the effects of high-intensity interval training (HIIT) versus moderate-intensity continuous training (MICT) on exercise capacity and health-related quality of life (HRQoL) in patients with coronary artery disease.

METHODS

We searched MEDLINE/PubMed, the Cochrane Library EMBASE, and the PEDro database for randomized controlled trials that evaluated the effects of HIIT versus MICT. Mean difference and 95 % confidence intervals (CI) were calculated.

RESULTS

27 studies, with 1454 patients, met the eligibility criteria. Twenty-four studies with 1259 patients assessed peak oxygen consumption (VO2peak) as an outcome. The HIIT group showed an increase of VO2peak (MD = 2.11 mL/kg/min; 95 % CI: 1.14, 3.07; I2 = 78 %; N = 1259) compared with the MICT group. Six studies with 316 patients assessed HRQoL as outcome. No differences in physical, emotional, and social domains of HRQoL were found between the HIIT and MICT groups. In the subgroup analysis of 10 studies with isocaloric exercise training, the HIIT and MICT groups showed similar VO2peak (MD = 0.72 mL/kg/min; 95 % CI: -0.03, 1.48; I2 = 44 %; N = 453).

CONCLUSIONS

Our meta-analysis showed low-quality evidence that HIIT training was more effective than MICT for improving VO2peak but not HRQoL in patients with coronary artery disease. However, when the analysis was limited to isocaloric protocols no difference between HIIT and MICT was found for VO2peak.

Global consensus on optimal exercise recommendations for enhancing healthy longevity in older adults (ICFSR)

Aging, a universal and inevitable process, is characterized by a progressive accumulation of physiological alterations and functional decline over time, leading to increased vulnerability to diseases and ultimately mortality as age advances. Lifestyle factors, notably physical activity (PA) and exercise, significantly modulate aging phenotypes. Physical activity and exercise can prevent or ameliorate lifestyle-related diseases, extend health span, enhance physical function, and reduce the burden of non-communicable chronic diseases including cardiometabolic disease, cancer, musculoskeletal and neurological conditions, and chronic respiratory diseases as well as premature mortality. Physical activity influences the cellular and molecular drivers of biological aging, slowing aging rates-a foundational aspect of geroscience. Thus, PA serves both as preventive medicine and therapeutic agent in pathological states. Sub-optimal PA levels correlate with increased disease prevalence in aging populations. Structured exercise prescriptions should therefore be customized and monitored like any other medical treatment, considering the dose-response relationships and specific adaptations necessary for intended outcomes. Current guidelines recommend a multifaceted exercise regimen that includes aerobic, resistance, balance, and flexibility training through structured and incidental (integrated lifestyle) activities. Tailored exercise programs have proven effective in helping older adults maintain their functional capacities, extending their health span, and enhancing their quality of life. Particularly important are anabolic exercises, such as Progressive resistance training (PRT), which are indispensable for maintaining or improving functional capacity in older adults, particularly those with frailty, sarcopenia or osteoporosis, or those hospitalized or in residential aged care. Multicomponent exercise interventions that include cognitive tasks significantly enhance the hallmarks of frailty (low body mass, strength, mobility, PA level, and energy) and cognitive function, thus preventing falls and optimizing functional capacity during aging. Importantly, PA/exercise displays dose-response characteristics and varies between individuals, necessitating personalized modalities tailored to specific medical conditions. Precision in exercise prescriptions remains a significant area of further research, given the global impact of aging and broad effects of PA. Economic analyses underscore the cost benefits of exercise programs, justifying broader integration into health care for older adults. However, despite these benefits, exercise is far from fully integrated into medical practice for older people. Many healthcare professionals, including geriatricians, need more training to incorporate exercise directly into patient care, whether in settings including hospitals, outpatient clinics, or residential care. Education about the use of exercise as isolated or adjunctive treatment for geriatric syndromes and chronic diseases would do much to ease the problems of polypharmacy and widespread prescription of potentially inappropriate medications. This intersection of prescriptive practices and PA/exercise offers a promising approach to enhance the well-being of older adults. An integrated strategy that combines exercise prescriptions with pharmacotherapy would optimize the vitality and functional independence of older people whilst minimizing adverse drug reactions. This consensus provides the rationale for the integration of PA into health promotion, disease prevention, and management strategies for older adults. Guidelines are included for specific modalities and dosages of exercise with proven efficacy in randomized controlled trials. Descriptions of the beneficial physiological changes, attenuation of aging phenotypes, and role of exercise in chronic disease and disability management in older adults are provided. The use of exercise in cardiometabolic disease, cancer, musculoskeletal conditions, frailty, sarcopenia, and neuropsychological health is emphasized. Recommendations to bridge existing knowledge and implementation gaps and fully integrate PA into the mainstream of geriatric care are provided. Particular attention is paid to the need for personalized medicine as it applies to exercise and geroscience, given the inter-individual variability in adaptation to exercise demonstrated in older adult cohorts. Overall, this consensus provides a foundation for applying and extending the current knowledge base of exercise as medicine for an aging population to optimize health span and quality of life.

Comparison of high-intensity interval training and moderate-intensity continuous training on cardiopulmonary function, cardiac autonomic function and vascular function in adolescent boys with obesity: A randomized controlled trial

Adolescent obesity can impair cardiopulmonary function, vascular elasticity, endothelial function, and vago-sympathetic balance. While moderate-intensity continuous training (MICT) benefits cardiovascular health in obese adolescents, the effects of high-intensity interval training (HIIT) are less understood. We hypothesize that HIIT may be more effective than MICT in improving VO2peak, vascular elasticity, endothelial function, and vago-sympathetic balance in obese adolescent boys. Forty four participants were randomly assigned to the HIIT (10 × 1-min at 85%-95% peak HR, intersperse with 2-min active recovery at 60%-70% peak HR) or MICT (35 min at 65%-75% peak HR) for an 8-week program. The primary outcome measured was the change in VO2peak with secondary outcomes including brachial-ankle pulse wave velocity (baPWV), flow-mediated dilation (FMD), and heart rate variability (HRV). Forty four adolescent boys with obesity (age, 14 ± 1 years old, body mass index, 31.6 ± 1.3 kg/m2) were enrolled and 43 (97.73%) completed the 8-week exercise. No significant difference of VO2peak was found between the HIIT and MICT group (p = 0.243). There was no significant difference of baPWV between the groups (p = 0.789). Change in FMD% was significantly higher in the HIIT group compared to the MICT group (p < 0.001). The Change in HRV-high frequency (HRV-HF; p = 0.009) and HRV-low frequency/high frequency (HRV-LF/HF; p = 0.035) was significantly higher in the HIIT group compared to the MICT group. Among adolescent boys with obesity, 8-week HIIT and MICT had similar effects on improving VO2peak. HIIT may be superior to MICT to improve endothelial function and vago-sympathetic balance.

Effect of high-intensity intermittent rehabilitation training on physical function, gut microbiome and metabolite after percutaneous coronary intervention in patients with coronary heart disease

Background

Postoperative rehabilitation exercise training after percutaneous coronary intervention (PCI) is crucial for coronary heart disease (CHD) patients in restoring health and preventing recurrence, including high-intensity interval training (HIIT). However, the impact of HIIT on cardiopulmonary function, gut microbiome and metabolite remains underexplored.

Methods

This study included 60 patients with CHD who underwent percutaneous coronary intervention (PCI). Participants were divided into two groups: 33 in the moderate-intensity continuous training (MCT) group and 27 in the high-intensity interval training (HIIT) group. We assessed difference between two training in cardiopulmonary function, 6-minute walk test (6MWT) performance, biochemical indicators, plasma metabolites, and gut microbiome feature at baseline and after 3 months training. Furthermore, we analyzed 6MWT association to gut microbiome and metabolites with group differences.

Results

The 6MWT showed significantly greater improvement in the HIIT group compared to the MCT group (P = 0.0024). Both groups showed reductions in low-density lipoprotein (LDL) levels and increases in peak oxygen uptake (VO2 peak) after training, but the HIIT group demonstrated a larger effect size in these measures. Moreover, subgroup analysis revealed that patients with a history of myocardial infarction (MI) in the HIIT group experienced a more substantial increase in VO2 peak compared to the MCT group (P = 0.04). In addition, we identified 29 gut microbial species and 30 plasma metabolites that were differentially enriched between the two groups, with some showing a significant impact on 6MWT performance.

Conclusions

High-intensity interval training significantly improves 6MWT performance and exercise tolerance in cardiac rehabilitation patients, particularly enhancing VO2 peak in those with a history of MI. HIIT also appears to modulate the gut microbiome, increasing the abundance of Clostridiales and decreasing traumatic acid content, which may contribute to the observed improvements in exercise tolerance.

High-Intensity Interval Training vs. Medium-Intensity Continuous Training in Cardiac Rehabilitation Programs: A Narrative Review

Exercise-based cardiac rehabilitation (ExCR) programs are essential for patients diagnosed with cardiac diseases. Studies have shown that they aid in the rehabilitation process and may even facilitate a return to previous cardiorespiratory fitness. Also, patients who enroll and follow such programs have shown a lower rate of complications and mortality in the long run. The results vary depending on the type of program followed and the degree of debilitation the disease has caused. Therefore, in order to obtain optimal results, it is ideal to tailor each ExCR program to the individual profile of each patient. At the moment, the two most studied and employed training types are medium-intensity continuous training (MICT) and high-intensity interval training (HIIT). For most of the time, MICT was the first-choice program for patients with cardiovascular disease. In recent years, however, more and more studies have pointed towards the benefits of HIIT and how it better aids patients in recovering their cardiovascular fitness. Generally, MICT is more suited for patients with a severe degradation in functional capacity and who require a higher degree of safety (e.g., elderly, with a high number of comorbidities). On the other hand, while HIIT is more demanding, it appears to offer better outcomes. Therefore, this review aimed to summarize information from different publications on both types of training regimens in ExCR and assess their utility in current clinical practice.

Effectiveness of a 12-week combining tai chi and yoga program on pulmonary function and functional fitness in COPD patients

BACKGROUND

Chronic obstructive pulmonary disease (COPD) poses significant challenges to both patients and healthcare providers due to its progressive nature and adverse impact on respiratory function and quality of life (QoL). While pulmonary rehabilitation remains a cornerstone of non-pharmacological COPD management, additional interventions are needed to address patients' diverse needs and preferences.

AIM

This study investigated the feasibility and potential benefits of a 12-week combining Tai Chi and Yoga (TY combining) program on cardiorespiratory and lung functions, functional fitness, and QoL in older males diagnosed with COPD.

METHODS

Twenty-four male COPD patients (age: 70 ± 6 years) with moderate to severe disease were recruited and randomized into the TY combining group (n = 12) or control group (n = 12). Assessments were conducted at baseline and at week 12, including pulmonary function tests, quality of life measures, dyspnea, and fatigue. Functional fitness tests were assessed at baseline, week 4, week 8, and week 12.

RESULTS

The TY combining program significantly improved pulmonary functions, functional fitness, quality of life, and fatigue over the 12-week intervention period. Notably, improvements in functional fitness parameters were observed after just four weeks of training, emphasizing the rapid benefits of the intervention. Moreover, the program exhibited high safety and feasibility, with no reported complications.

CONCLUSION

The 12-week TY combining program represents a safe, feasible, and effective adjunctive therapy for COPD management in older male patients. By addressing multiple dimensions of health and functioning, including pulmonary and cardiovascular health, functional fitness, and quality of life, this holistic approach holds promise for optimizing outcomes in COPD patients. Further research is warranted to validate these findings and explore optimal implementation strategies in clinical practice.

Core Components of Cardiac Rehabilitation Programs: 2024 Update: A Scientific Statement From the American Heart Association and the American Association of Cardiovascular and Pulmonary Rehabilitation

The science of cardiac rehabilitation and the secondary prevention of cardiovascular disease has progressed substantially since the most recent American Heart Association and American Association of Cardiovascular and Pulmonary Rehabilitation update on the core components of cardiac rehabilitation and secondary prevention programs was published in 2007. In addition, the advent of new care models, including virtual and remote delivery of cardiac rehabilitation services, has expanded the ways that cardiac rehabilitation programs can reach patients. In this scientific statement, we update the scientific basis of the core components of patient assessment, nutritional counseling, weight management and body composition, cardiovascular disease and risk factor management, psychosocial management, aerobic exercise training, strength training, and physical activity counseling. In addition, in recognition that high-quality cardiac rehabilitation programs regularly monitor their processes and outcomes and engage in an ongoing process of quality improvement, we introduce a new core component of program quality. High-quality program performance will be essential to improve widely documented low enrollment and adherence rates and reduce health disparities in cardiac rehabilitation access.

The Effect of Acute Aerobic Exercise on Biomarkers of Renal Health and Filtration in Moderate-CKD

Purpose: Efficacy of exercise to improve renal health and filtration remains understudied in adults with moderate-stages (stages G3a-b) of chronic kidney disease (CKD). Acute exercise may contribute clinically relevant information for exercise-related augmentation of renal health and filtration in CKD. Urine epidermal growth factor (uEGF) and cystatin C (CyC) are proposed to be more direct biomarkers of renal health and filtration. This study aimed to determine the influence of continuous moderate-intensity exercise (CMIE) and high-intensity interval exercise (HIIE) on traditional and novel biomarkers of renal health and filtration in moderate-stages of CKD. Methods: Twenty CKD participants completed 30 minutes of both CMIE and HIIE. Blood and urine samples were obtained pre, 1-hour, and 24-hours post-exercise. Traditional-serum creatinine (sCr) urine creatinine, novel-uEGF, uEGF ratio (uEGFr), and CyC. Estimates of glomerular filtration rate (eGFR)-modification of diet in renal disease (MDRD) and the CKD-Epidemiology (CKD-EPI)-responses were compared pre, 1 hr, and 24 hr post-exercise. Results: Relative to pre-exercise measures, uEGF remained unchanged in both exercise conditions. However, uEGFr was 5.4% greater 24-hours after HIIE (P = .05), while uEGFr remained unchanged with CMIE. sCr decreased 6 to 19% 1-hour post-exercise in both conditions (P = .009). On average renal filtration increased in eGFR-MDRD (7.2 ± 2.0 ml/min/1.73 m2) (P = .007) and eGFR-CKD-EPI (8.6 ± 2.3 ml/min/1.73 m2) 1-hour post-exercise (P = .009). Conclusion: By clinical estimates, renal filtration in CKD was not normalized but transiently improved regardless of exercise condition, with HIIE eliciting transient improvements in renal health.

Rates of compliance and adherence to high-intensity interval training: a systematic review and Meta-analyses

BACKGROUND

To determine rates of compliance (i.e., supervised intervention attendance) and adherence (i.e., unsupervised physical activity completion) to high-intensity interval training (HIIT) among insufficiently active adults and adults with a medical condition, and determine whether compliance and adherence rates were different between HIIT and moderate-intensity continuous training (MICT).

METHODS

Articles on adults in a HIIT intervention and who were either insufficiently active or had a medical condition were included. MEDLINE, EMBASE, PsychINFO, SPORTDiscus, CINAHL, and Web of Science were searched. Article screening and data extraction were completed by two independent reviewers. Risk of bias was assessed using RoB 2.0 or ROBINS-I. Meta-analyses were conducted to discern differences in compliance and adherence between HIIT vs. MICT. Sensitivity analyses, publication bias, sub-group analyses, and quality appraisal were conducted for each meta-analysis.

RESULTS

One hundred eighty-eight unique studies were included (n = 8928 participants). Compliance to HIIT interventions averaged 89.4% (SD:11.8%), while adherence to HIIT averaged 63% (SD: 21.1%). Compliance and adherence to MICT averaged 92.5% (SD:10.6%) and 68.2% (SD:16.2%), respectively. Based on 65 studies included in the meta-analysis, compliance rates were not different between supervised HIIT and MICT interventions [Hedge's g = 0.015 (95%CI: - 0.088-0.118), p = .78]. Results were robust and low risk of publication bias was detected. No differences were detected based on sub-group analyses comparing medical conditions or risk of bias of studies. Quality of the evidence was rated as moderate over concerns in the directness of the evidence. Based on 10 studies, adherence rates were not different between unsupervised HIIT and MICT interventions [Hedge's g = - 0.313 (95%CI: - 0.681-0.056), p = .096]. Sub-group analysis points to differences in adherence rates dependent on the method of outcome measurement. Adherence results should be interpreted with caution due to very low quality of evidence.

CONCLUSIONS

Compliance to HIIT and MICT was high among insufficiently active adults and adults with a medical condition. Adherence to HIIT and MICT was relatively moderate, although there was high heterogeneity and very low quality of evidence. Further research should take into consideration exercise protocols employed, methods of outcome measurement, and measurement timepoints.

REGISTRATION

This review was registered in the PROSPERO database and given the identifier CRD42019103313.

The Effect of High-Intensity Interval Training on Exercise Capacity in Patients with Coronary Artery Disease: A Systematic Review and Meta-Analysis

Background

The optimal exercise prescription for coronary artery disease (CAD) remains under debate. The aim of our meta-analysis is to investigate the efficacy of high-intensity interval training (HIIT) versus moderate-intensity continuous training (MICT) of coronary artery disease patients.

Methods

Electronic databases were searched from their inception date until October 23, 2021, and the articles include randomized controlled trials. The mean differences and 95% confidence intervals were calculated, and heterogeneity was assessed using the I 2 test.

Results

The study standards were met by seventeen studies. The pooled studies included 902 patients. HIIT resulted in improvement in peak oxygen uptake (1.50 ml/kg/min, 95% confidence interval: 0.48 to 2.53, n = 853 patients, and low quality evidence) compared with MICT. There was no discernible difference between the individuals in the HIIT group and the MICT group in terms of systolic/diastolic blood pressure or peak/resting heart rate.

Conclusion

This systematic review and meta-analysis reported the superiority of HIIT versus MICT in enhancing peak oxygen uptake in CAD patients.

Acute physiological responses to high-intensity interval exercise in patients with coronary artery disease

PURPOSE

Time spent closer to maximal effort during exercise is a potent stimulus for cardiorespiratory adaptations. The primary purpose was to determine which high-intensity interval exercise (HIIE) protocol provided the greatest physiological stimulus by comparing time spent ≥ 90% peak oxygen consumption (V̇O₂peak) and heart rate reserve (HRR) in patients with coronary artery disease (CAD) in response to 3 HIIE protocols and the exercise standard of care, moderate-intensity continuous exercise (MICE). A secondary purpose was to assess protocol preference.

METHODS

Fifteen patients with CAD (6 females, 67 ± 6 years) underwent measurements of V̇O₂ and heart rate during MICE and three HIIE protocols all performed on a treadmill. The HIIE protocols included one with long intervals (4 × 4-min), short intervals (10 × 1-min), and an adapted version of the 4 × 4 [Toronto Rehabilitation Institute Protocol, (TRIP)]. Time spent ≥ 90% V̇O₂peak and HRR were compared.

RESULTS

Time spent ≥ 90% V̇O₂peak was higher during 4 × 4 (6.3 ± 8.4 min) vs. MICE (1.7 ± 3.9 min; P = 0.001), while time spent ≥ 90% HRR was higher during 4 × 4 (6.0 ± 5.3 min) vs. MICE (0.1 ± 0.2 min; P < 0.001) and 10 × 1 (0.7 ± 0.8 min; P = 0.016). TRIP had similar responses as 10 × 1 and MICE. The 10 × 1 was the most preferred protocol and the 4 × 4 was the least preferred protocol.

CONCLUSION

Longer intervals (4 × 4) provided the greatest physiological stimulus compared to the exercise standard of care and shorter intervals. However, this protocol was least preferred which may impact exercise adherence. Although the physiological stimulus is important to maximize training adaptations, exercise preferences and attitudes should be considered.

Influence of Two Exercise Programs on Heart Rate Variability, Body Temperature, Central Nervous System Fatigue, and Cortical Arousal after a Heart Attack

Cardiovascular diseases (CVD) are the leading cause of death globally. Cardiac rehabilitation (CR) programs' benefits are overall consensual; however, during exercise, progressive physiological effects have not been studied yet in cardiac patients. Our study aims to analyze physiological parameters of thermography, heart rate variability (HRV), blood pressure, central nervous system (CNS) fatigue, and cortical arousal in heart attack patients (HAP) who belong to CR programs of High-Intensity Interval Training (HIIT) and Moderate-intensity Continuous Training (MICT) compared to healthy participants. In this case control study, two HAP patients (both male, age 35 and 48, respectively) and two healthy people (both male, age 38 and 46, respectively) were randomly assigned in a 1:1:1:1 allocation ratio to one of four groups: cardiac MICT, cardiac HIIT, control MICT, and control HIIT. The HIIT at ≈85-95% of peak heart rate (HR) was followed by a one-minute recovery interval at 40% peakHR, and MICT at ≈70-75% of peakHR. Outcome measurements included thermography, HRV, blood pressure, CNS fatigue, and cortical arousal; The HAP presents more than twice the CNS fatigue in MICT than control participants, but HIIT has almost the same CNS fatigue in HAP and control. In addition, both of the HAP groups presented higher temperatures in the chest. The HIIT protocol showed better physiological responses during exercise, compared to MICT in HAP.

German volume training for health promotion: Acute vasopressor, pulmonary and metabolic responses

Resistance training (RT) is increasingly recommended for incorporation into comprehensive fitness or "exercise as medicine" programs. However, the acute effects of RT, and especially its different sub-types, and how they impact health outcomes are not fully investigated. This study evaluated German Volume Training (GVT) ("10 set × 10 rep scheme") for its efficacy for its use in health settings. This study utilized a randomized crossover design with subjects serving as their own controls to establish baseline values. Subjects were blinded to the study hypothesis. Subjects performed a single session of GVT or no exercise, in a randomised order separated by a 1-week washout period. Outcomes were assessed before and immediately post-exercise. GVT significantly (p < 0.05) decreased systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP), but increased heart rate (HR), rate pressure product (RPP) and rating of perceived exertion (RPE). No changes were found in the measured spirometry parameters. Increases were observed in carbon dioxide production (VCO₂) and minute ventilation (V_E), but not respiratory exchange ratio. Post hoc analysis demonstrated that post-GVT values were significantly lower for SBP (p = 0.017; d = 1.00), DBP (p = 0.013; d = 0.90), MAP (p = 0.024; d = 1.06), and VCO₂ (p = 0.009; d = -1.32), and significantly higher for RPP (p = 0.001; d = -3.11), RPE (p = 0.001; d = -14.14), and HR (p = 0.001; d = -3.00). This study indicates that acute GVT promotes post-exercise hypotension and is of sufficient intensity to increase both objective HR and subjective RPE intensities appropriately for use in a variety of health promotion settings.

Effect of Exercise on Carotid Artery Intima-Media Thickness in Adults: A Systematic Review and Meta-Analysis

BACKGROUND

Carotid intima-media thickness (cIMT) is a validated surrogate marker of atherosclerosis that is independently associated with the risk for cardiovascular disease. Recent studies on the effect of exercise on cIMT have yielded conflicting results.

METHODS

Studies that were available up until October 30, 2021 from the PubMed, Cochrane Library, Embase, and Web of Science databases were included in the analysis. Subgroup analyses were performed to determine the effects of the type, intensity, and duration of exercise on cIMT.

RESULTS

This review included 26 studies with 1370 participants. Compared with control participants, those who engaged in exercise showed a decline in cIMT (weighted mean difference [WMD] -0.02; 95% confidence interval [CI], -0.03 to -0.01; I2 = 90.1%). Participants who engaged in aerobic (WMD -0.02; 95% CI, -0.04 to -0.01; I2 = 52.7%) or resistance (WMD -0.01; 95% CI, -0.02 to -0.00; I2 = 38.5%) exercise showed lower cIMT compared with control participants. An exercise duration of >6 months was associated with a 0.02 mm reduction in cIMT. In participants with low cIMT at baseline (<0.7 mm), exercise alone was not associated with a change in cIMT (WMD -0.01; 95% CI, -0.03 to 0.00; I2 = 93.9%).

CONCLUSIONS

Exercise was associated with reduced cIMT in adults. Aerobic exercise is associated with a greater decline in cIMT than other forms of exercise. Large, multicenter, randomized controlled trials are required to establish optimal exercise protocols for improving the pathological process of atherosclerosis.

Arterial Stiffness Response to Acute Combined Training with Different Volumes in Coronary Artery Disease and Heart Failure Patients

Resistance training has been shown to acutely increase arterial stiffness (AS), while endurance training appears to decrease AS. However, the findings are from studies in apparently healthy subjects and have limited applicability to patients at low and high cardiovascular risk, for whom combined exercise is recommended. We compared the time course of changes in local and regional indices of AS in response to high-volume combined endurance training (CET) and high-volume combined resistance training (CRT) in patients with coronary artery disease (CAD) and heart failure (HF). We studied 20 men with CAD and HF (10 each) aged 68.3 ± 9.6 years. AS was measured by pulse wave velocity (PWV), and brachial and central blood pressure (BP) were determined after 15 min of rest and 5 and 15 min after the exercise session. All patients completed two sessions on nonconsecutive days. A protocol by time interaction effect was observed for carotid (η² = 0.21, p = 0.02), aortic (η² = 0.60, p < 0.001), and femoral (η² = 0.46, p = 0.01) PWV after CET and CRT, suggesting that PWV decreased after CET and increased after CRT. Decreases in the brachial and central variables of BP across time points were observed in both protocols. CET decreased whereas CRT increased carotid, aortic, and femoral PWV at 15 min after exercise in patients with CAD and HF.

Arterial Stiffness following Endurance and Resistance Exercise Sessions in Older Patients with Coronary Artery Disease

Arterial stiffness (AS) is associated with coronary artery disease (CAD). Acute endurance training decreases AS, whereas acute resistance training increases it. However, these results are from studies in apparently healthy adults, and there is no information on the effects of such afterload AS in elderly patients with CAD. We aimed to investigate the effect of acute endurance or resistance training on the time course of changes in the indices of AS in elderly patients with CAD in order to understand how stiffness responds after training. We tested 18 trained men with CAD. AS was measured using central and peripheral pulse wave velocity (PWV) after 15 min of rest and after 5, 15, and 30 min of endurance and resistance training sessions. The endurance session consisted of high-intensity interval walking at 85-90% of maximum heart rate, and the resistance session consisted of 70% of the maximum of one repetition. An interaction effect was found for central and peripheral PWV (p ≤ 0.001; carotid, η² = 0.72; aortic, η² = 0.90; femoral, η² = 0.74), which was due to an increase in PWV after resistance and a decrease in central and peripheral PWV after endurance. This study demonstrates that training mode influences the time course of AS responses to acute exercise in these patients. Acute endurance training decreased AS, whereas resistance training significantly increased it.

Feasibility and impact of whole-body high-intensity interval training in patients with stable coronary artery disease: a randomised controlled trial

Exercise training reduces cardiovascular mortality and improves quality of life in CAD patients. We investigated the feasibility and impact of 12 weeks of low-volume high-intensity interval training (HIIT) in CAD-patients. Patients with stable CAD were randomized 1:1 to supervised HIIT or standard care. HIIT sessions were completed three times weekly for 12 weeks on a rowing ergometer. Before and after the 12-week intervention, patients completed a physiological evaluation of cardiorespiratory performance and quality of life questionnaires. Mixed model analysis was used to evaluate differences between and within groups. A total of 142 patients (67 ± 9 years, n_HIIT = 64, n_{Standard care} = 78) completed the trial. Training adherence was 97% (range 86-100%). Six patients dropped out because of non-fatal adverse events. Weekly training duration was 54 min with an average power output of 138 W. HIIT increased peak oxygen uptake by 2.5 mL/kg/min (95% CI 2.1-3.0), whereas no change was observed in standard care (0.2 mL/kg/min, 95% CI - 0.2-0.6, P < 0.001). In addition, HIIT improved markers of quality of life, including physical functioning, limitations due to physical illness, general health and vitality (P < 0.05). Twelve weeks of low-volume whole-body HIIT increased cardiorespiratory capacity and improved quality of life in patients with stable CAD compared to standard care. In addition, our study demonstrates that the applied vigorous training regime is feasible for this patient group.Clinical trial registration: www.clinicaltrials.gov . Identification number: NCT04268992.

The Comparison of High-Intensity Interval Training Versus Moderate-Intensity Continuous Training after Coronary Artery Bypass Graft: A Systematic Review of Recent Studies

Currently, no international consensus on cardiac rehabilitation exists, leading to great variability in the intensity recommendations for training programs for cardiac patients, including those undergoing coronary artery bypass graft surgery (CABG). While some countries prefer the high-intensity interval training (HIIT) method to improve cardiorespiratory fitness, other countries opt for moderate-intensity continuous training (MICT). The aim of this systematic review was to compare the effects of HIIT and MICT on aerobic fitness and quality of life (QoL) in patients undergoing CABG with the intention of providing support for a consensus on exercise therapy.

METHODS

A systematic review of randomized controlled trials (RCTs) was conducted using the online publication databases PubMed, the Cochrane Library and the Bibliothèque nationale du Luxembourg (BnL) covering the last ten years to July 2022. Relevant identified studies respecting the inclusion/exclusion criteria were selected, screened and extracted by four reviewers. Furthermore, the methodological quality of the clinical trials was assessed using the PEDro scale, which was reinforced using the Cochrane Risk of Bias Tool for Randomized Trials (RoB2) for the evaluation of the risk of bias to provide more detail in the evaluation. The certainty of the evidence analysis was established using different levels of evidence in accordance with the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) framework.

RESULTS

A total of 379 patients from five RCTs diagnosed with coronary artery disease, including patients undergoing CABG, performed aerobic exercise over different time periods and were assessed based on peakVO2, VO2max and QoL. Overall, both training methods provided improvements in cardiorespiratory fitness and quality of life, with greater changes in HIIT groups.

CONCLUSION

Both trainings methods provide improvements in cardiorespiratory fitness and QoL, with greater increases from HIIT. The moderate quality of evidence supports the use of HIIT and MICT to improve cardiorespiratory fitness and QoL.

Effects of high-intensity and moderate-intensity exercise training on cardiopulmonary function in patients with coronary artery disease: A meta-analysis

Purpose

The study aims to evaluate the effects of high-intensity and moderate-intensity exercise training on cardiopulmonary function and exercise endurance in patients with coronary artery diseases (CAD).

Methods

We performed a systematic search of the English and Chinese databases from their inception to March 2022. Randomized controlled trials (RCTs) were included to compare high-intensity and moderate-intensity exercise training on cardiopulmonary function in patients with CAD. The primary outcomes included peak oxygen uptake (peak VO₂) and anaerobic threshold (AT). The secondary outcomes included left ventricular ejection fraction (LVEF), exercises duration (ED), respiratory exchange ratio (RER), resting heart rate (RHR), peak heart rate (PHR) and oxygen pulse (O₂ pulse). The continuous variables were expressed as mean differences (MD) along with their corresponding standard deviations (SD), and the I² test was applied in the assessment of heterogeneity.

Results

After systematically literature search, 19 studies were finally selected for our meta-analysis (n = 1,036), with 511 patients in the experimental group (high-intensity exercise) and 525 patients in the control group (moderate-intensity exercise). The results showed that high-intensity exercise significantly increased patients' Peak VO₂ [MD = 2.67, 95% CI (2.24, 3.09), P < 0.00001], LVEF [MD = 3.60, 95% CI (2.17, 5.03), P < 0.00001], ED [MD = 37.51, 95% CI (34.02, 41.00), P < 0.00001], PHR [MD = 6.86, 95% CI (4.49, 9.24), P < 0.00001], and O₂ pulse [MD = 0.97, 95% CI (0.34, 1.60), P = 0.003] compared with moderate-intensity exercise. However, there were no significant differences in AT [MD = 0.49, 95% CI (−0.12, 1.10), P = 0.11], RER [MD = 0.00, 95% CI (−0.01, 0.02), P = 0.56], and RHR [MD = 1.10, 95% CI (−0.43, 2.63), P = 0.16].

Conclusion

Our results show that high-intensity exercise training has more significant positive effects compared with moderate-intensity exercise training in improving peak VO₂, LVEF, ED, PHR and O₂ pulse in patients with CAD, while no significant differences were observed in AT, RER and RHR. To sum up, high-intensity exercise training is better than moderate-intensity exercise training in improving cardiopulmonary function and exercise endurance in patients with CAD.

Systematic review registration

PROSPERO (CRD42022328475), https://www.crd.york.ac.uk/PROSPERO/.

Effectiveness of High-Intensity Interval Training and Continuous Moderate-Intensity Training on Blood Pressure in Physically Inactive Pre-Hypertensive Young Adults

The likelihood of pre-hypertensive young adults developing hypertension has been steadily increasing in recent years. Despite the fact that aerobic exercise training (AET) has demonstrated positive results in lowering high blood pressure, the efficacy of different types of AET among pre-hypertensive young adults has not been well-established. The objective of this study was to evaluate the effectiveness of high-intensity interval training (HIIT) and continuous moderate-intensity training (CMT) on the blood pressure (BP) of physically inactive pre-hypertensive young adults. In total, 32 adults (age 20.0 ± 1.1 years and BMI 21.5 ± 1.8) were randomly assigned to three groups: HIIT, CMT and control (CON). The HIIT and CMT groups participated in 5 weeks of AET, while the CON group followed a DASH diet plan only. The HIIT protocol consisted of a 1:4 min work to rest ratio of participants, at an 80−85% heart rate reserve (HR-reserve) and a 40−60% HR-reserve, respectively, for 20 min; the CMT group exercised at 40−60% of their HR-reserve continuously for 20 min. In both the HIIT and CMT groups, systolic blood pressure (SBP) (3.8 ± 2.8 mmHg, p = 0.002 vs. 1.6 ± 1.5 mmHg, p = 0.011) was significantly reduced, while significant reductions in the diastolic blood pressure (DBP) (2.9 ± 2.2 mmHg, p = 0.002) and mean arterial pressure (MAP) (3.1 ± 1.6 mmHg, p < 0.0005) were noted only in the HIIT group. No significant differences in SBP (−0.4 ± 3.7 mmHg, p = 0.718), DBP (0.4 ± 3.4 mmHg, p = 0.714), or MAP (0.1 ± 2.5 mmHg, p = 0.892) were observed in the CON group. Both HIIT and CMT decreased BP in physically inactive pre-hypertensive young adults; however, HIIT yielded more beneficial results in terms of reducing the SPB, DBP and MAP.

Short- and Long-Term Effects of High-Intensity Interval Training vs. Moderate-Intensity Continuous Training on Left Ventricular Remodeling in Patients Early After ST-Segment Elevation Myocardial Infarction-The HIIT-EARLY Randomized Controlled Trial

Aim

Due to insufficient evidence on the safety and effectiveness of high-intensity interval training (HIIT) in patients early after ST-segment elevation myocardial infarction (STEMI), we aimed to compare short- and long-term effects of randomized HIIT or moderate-intensity continuous training (MICT) on markers of left ventricular (LV) remodeling in STEMI patients receiving optimal guideline-directed medical therapy (GDMT).

Materials and Methods

Patients after STEMI (<4 weeks) enrolled in a 12-week cardiac rehabilitation (CR) program were recruited for this randomized controlled trial (NCT02627586). During a 3-week run-in period with three weekly MICT sessions, GDMT was up-titrated. Then, the patients were randomized to HIIT or isocaloric MICT for 9 weeks. Echocardiography and cardiopulmonary exercise tests were performed after run-in (3 weeks), end of CR (12 weeks), and at 1-year follow-up. The primary outcome was LV end-diastolic volume index (LVEDVi) at the end of CR. Secondary outcomes were LV global longitudinal strain (GLS) and cardiopulmonary fitness.

Results

Seventy-three male patients were included, with the time between STEMI and start of CR and randomization being 12.5 ± 6.3 and 45.8 ± 10.8 days, respectively. Mixed models revealed no significant group × time interaction for LVEDVi at the end of CR (p = 0.557). However, there was a significantly smaller improvement in GLS at 1-year follow-up in the HIIT compared to the MICT group (p = 0.031 for group × time interaction). Cardiorespiratory fitness improved significantly from a median value of 26.5 (1st quartile 24.4; 3rd quartile 1.1) ml/kg/min at randomization in the HIIT and 27.7 (23.9; 31.6) ml/kg/min in the MICT group to 29.6 (25.3; 32.2) and 29.9 (26.1; 34.9) ml/kg/min at the end of CR and to 29.0 (26.6; 33.3) and 30.6 (26.0; 33.8) ml/kg/min at 1 year follow-up in HIIT and MICT patients, respectively, with no significant group × time interactions (p = 0.138 and 0.317).

Conclusion

In optimally treated patients early after STEMI, HIIT was not different from isocaloric MICT with regard to short-term effects on LVEDVi and cardiorespiratory fitness. The worsening in GLS at 1 year in the HIIT group deserves further investigation, as early HIIT may offset the beneficial effects of GDMT on LV remodeling in the long term.

Fit, Female or Fifty–Is Cardiac Rehabilitation “Fit” for Purpose for All? A Systematic Review and Meta-Analysis With Meta-Regression

Aims

Cardiac rehabilitation (CR) is an evidence-based intervention promoting risk factor modification following coronary artery disease events but the relative benefits for patient subgroups is not clear. This review synthesizes the available evidence on the effectiveness of modern CR programs and determines outcomes for age, sex and prior level of fitness.

Methods

MEDLINE, CINAHL, and EMBASE were examined for RCT and cohort studies involving exercise prescription or phase II or III CR following Myocardial Infarction (MI), Percutaneous Coronary Intervention (PCI) and cardiac surgery from January 2010 to February 2021. Outcomes assessed included peakVO2max, 6-min walk test and Metabolic Equivalent of Task. Meta-regression was used to determine CR impact for change in fitness and age and sex influences.

Results

The mean age of study participants was 59.5 years and 82.7% were male. Females, younger people and those of average or above cardiorespiratory fitness were substantially under-represented in data and attendance, with 13% of study groups with a mean age &lt;55 years. At entry, 73% were below average for fitness vs. age-matched normative values. Fitness improved across all groups following CR with no evidence of sex or age independently affecting outcomes.

Conclusions

Modest improvements in fitness in all groups were shown, but the benefits of CR can be far greater. A modern, innovative approach to CR will likely lead to more substantial benefits. This may require a “Precision Medicine” model which tailors exercise prescription to different populations to ensure all CR participant's needs are met. This will ensure that CR is more flexible and accessible for all.

Effects of High-Intensity Interval vs. Moderate-Intensity Continuous Training on Cardiac Rehabilitation in Patients With Cardiovascular Disease: A Systematic Review and Meta-Analysis

Background

Studies have shown that high-intensity interval training (HIIT) is superior to moderate-intensity continuous training (MICT) for increasing peak oxygen uptake (VO_2peak) and reducing cardiovascular disease (CVD) and mortality. To our knowledge, previously published systematic reviews have neither compared different HIIT models with MICT nor investigated intervention frequencies of HIIT vs. MICT for purposes of improving cardiorespiratory fitness in patients with CVD.

Objective

The purpose of this meta-analysis was to compare the effects of different training models, intervention frequencies and weeks of HIIT vs. MICT on changes in cardiorespiratory fitness during cardiac rehabilitation (CR).

Methods

A systematic search was carried out for research articles on randomized controlled trials (RCTs) indexed in the PubMed, Cochrane Library, Web of Science, Embase and Scopus databases for the period up to December 2021. We searched for RCTs that compared the effect of HIIT vs. MICT on cardiorespiratory fitness in patients with CVD.

Results

Twenty-two studies with 949 participants (HIIT: 476, MICT: 473) met the inclusion criteria. Sensitivity analysis revealed that HIIT increased VO_2peak more than MICT (MD = 1.35). In the training models and durations, there was a greater increase in VO_2peak with medium-interval HIIT (MD = 4.02) and more than 12 weeks duration (MD = 2.35) than with MICT. There were significant improvements in VO_2peak with a HIIT frequency of 3 times/week (MD = 1.28). Overall, one minor cardiovascular and four non-cardiovascular adverse events were reported in the HIIT group, while six non-cardiovascular adverse events were reported in the MICT group.

Conclusion

HIIT is safe and appears to be more effective than MICT for improving cardiorespiratory fitness in patients with CVD. Medium-interval HIIT 3 times/week for more than 12 weeks resulted in the largest improvement in cardiorespiratory fitness during CR.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021245810, identifier: CRD42021245810.

High level physical activity in cardiac rehabilitation: Implications for exercise training and leisure-time pursuits

IMPORTANCE

Regular moderate-to-vigorous physical activity and increased levels of cardiorespiratory fitness (CRF) are widely promoted as cardioprotective measures in secondary prevention interventions.

OBSERVATIONS

A low level of CRF increases the risk of cardiovascular disease (CVD) to a greater extent than merely being physically inactive. An exercise capacity <5 metabolic equivalents (METs), generally corresponding to the bottom 20% of the fitness continuum, indicates a higher mortality group. Accordingly, a key objective in early cardiac rehabilitation (CR) is to increase the intensity of training to >3 METs, to empower patients to vacate this "high risk" group. Moreover, a "good" exercise capacity, expressed as peak METs, identifies individuals with a favorable long-term prognosis, regardless of the underlying extent of coronary disease. On the other hand, vigorous-to-high intensity physical activity, particularly when unaccustomed, and some competitive sports are associated with a greater incidence of acute cardiovascular events. Marathon and triathlon training/competition also have limited applicability and value in CR, are associated with acute cardiac events each year, and do not necessarily provide immunity to the development of or the progression of CVD. Furthermore, extreme endurance exercise regimens are associated with an increased incidence of atrial fibrillation and accelerated coronary artery calcification.

CONCLUSIONS AND RELEVANCE

High-intensity training offers a time-saving alternative to moderate intensity continuous training, as well as other potential advantages. Additional long-term studies assessing safety, adherence, and morbidity and mortality are required before high-intensity CR training can be more widely recommended, especially in previously sedentary patients with known or suspected CVD exercising in non-medically supervised settings.

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.

Comparison between bicycle ergometric interval and continuous training in patients early after coronary artery bypass grafting: A prospective, randomized study

Objectives:

Continuous and interval training have previously been compared in patients with cardiac diseases. However, data comparing the safety and effectiveness of the two exercise methods are lacking in patients early after coronary artery bypass grafting.

Methods:

In all, 120 patients were prospectively randomized in a 1:1 fashion approximately 17 days after coronary artery bypass grafting to an interval group or continuous group. All patients participated in bicycle ergometric training six times/week for 20 min each during a 3-week inpatient rehabilitation program. The combined primary endpoint was safety as defined by incidence of scar pain and cardiac events related to the exercise intervention. Secondary outcomes included the effect of the interventions on parameters such as heart rate and peak power output.

Results:

Four patients (12.1%) in the interval group reported pain on the saphenectomy scar as a result of the training intervention in comparison to six patients (20.0%) in the continuous group (χ² (1, n = 63) = 0.73, p = 0.393). No cardiac events were related to exercise intervention. No effect on heart rate was found during the intervention, nor was a difference observed between the groups. Peak power output, as one of the analyzed markers, improved significantly in both groups, but no differences were found between groups.

Conclusion:

Ergometry training performed as interval or continuous training was safe and effective regarding increase in physical fitness early after coronary artery bypass grafting in an inpatient rehabilitation setting, with no differences observed between the groups.

High-Intensity Interval Training in Patients with Pulmonary Embolism: A Randomized Controlled Trial

PURPOSE

High-intensity interval training (HIIT) appears to be safe and effective in cardiovascular diseases. However, there is a paucity of data on the effect of HIIT for patients with acute pulmonary embolism (PE). The present randomized controlled trial (RCT) therefore examined the efficiency and safety of HIIT in patients with acute PE.

METHODS

In single-center parallel open-label RCT, 24 patients (5 women) discharged recently with a diagnosis of intermediate-high risk acute PE were randomized (1:1) to supervised HIIT (n = 12) or control (n = 12) group. The primary outcomes were exercise capacity evaluated in terms of the estimated maximal oxygen uptake (eVO2max), lung function (forced expiratory volume in 1 second, FEV1), right ventricular (RV) function, (RV/left ventricle diameter (LV) ratio) and health related quality of life (HRQoL). Safety was the secondary outcome.

RESULTS

8-weeks of HIIT improved eVO2max (+65%, p < 0.001), FEV1 (%) (+17%, p = 0.031), and RV/LV ratio diameter (-27%, p = 0.005), as well as HRQoL. All patients in the HIIT group tolerated exercise training without serious adverse events. The control group did not improve (p > 0.05) eVO2max, RV/LV ratio diameter, or HRQoL; however, FEV1 (%) was slightly reduced (-6%, p = 0.030).

CONCLUSION

The present RCT of a tailored center based HIIT intervention provides preliminary evidence that this intervention could improve exercise capacity, lung function, RV function, and HRQoL without serious adverse events, which could provide marked clinical benefits following PE. Further larger multicenter randomized controlled studies are needed to confirm these promising findings.

Effectiveness of HIIE versus MICT in Improving Cardiometabolic Risk Factors in Health and Disease: A Meta-analysis

PURPOSE

We aimed to investigate differences between high-intensity interval exercise (HIIE, including high-intensity interval training and sprint interval training) and moderate-intensity continuous training (MICT) on physical fitness, body composition, blood pressure, blood lipids, insulin and glucose metabolism, inflammation, and endothelial function.

METHODS

Differences between HIIE and MICT were summarized using a random-effects meta-analysis on the effect size (Cohen's d). A meta-regression was conducted using the following subgroups: population, age, training duration, men ratio, exercise type, baseline values (clinical relevant ranges), and type of HIIE. Studies were included if at least one of the following outcomes were reported: maximal oxygen uptake (V˙O2max), flow-mediated dilation (FMD), body mass index (BMI), body mass, percent body fat, systolic and diastolic blood pressure, high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides, total cholesterol, C-reactive protein (CRP), fasting glucose and insulin, glycated hemoglobin (HbA1c), and insulin resistance (HOMA-IR). A total of 55 studies were included.

RESULTS

Overall, HIIE was superior to MICT in improving V˙O2max (d = 0.40, P < 0.001) and FMD (d = 0.54, P < 0.05). Oppositely, MICT was superior to HIIE in improving HbA1c (d = -0.27, P < 0.05). No differences were observed in BMI (d = -0.02), body mass (d = -0.05), percent body fat (d = 0.04), systolic blood pressure (d = -0.04), diastolic blood pressure (d = 0.03), HDL (d = -0.05), LDL (d = 0.08), triglycerides (d = 0.03), total cholesterol (d = 0.14), CRP (d = -0.11), fasting insulin (d = 0.02), fasting glucose (d = 0.02), and HOMA-IR (d = -0.04). Moderator analyses indicated that the difference between HIIE and MICT was affected by different subgroups.

CONCLUSION

Overall, HIIE showed to be more effective in improving cardiovascular health and cardiorespiratory fitness, whereas MICT was superior in improving long-term glucose metabolism. In the process of personalized training counseling, health-enhancing effects of exercise training may be improved by considering the individual risk profiles.

Adherence to High-Intensity Interval Training in Cardiac Rehabilitation: A REVIEW AND RECOMMENDATIONS

PURPOSE

High-intensity interval training (HIIT) is gaining popularity as a training approach for patients attending cardiac rehabilitation (CR). While the literature has focused on the efficacy of HIIT for improving cardiorespiratory fitness (CRF), particularly when compared with moderate intensity exercise, less emphasis has been placed on adherence to HIIT. The aim of this review was to summarize the current literature regarding adherence to HIIT in CR patients with coronary artery disease.

REVIEW METHODS

A review identified 36 studies investigating HIIT in CR patients with coronary artery disease. Methods and data were extracted for exercise or training adherence (to attendance, intensity, and duration), feasibility of protocols, and CRF. The review summarizes reporting of adherence; adherence to HIIT and comparator/s; the influence of adherence on changes in CRF; and feasibility of HIIT.

SUMMARY

Adherence to the attendance of HIIT sessions was high and comparable with moderate-intensity exercise. However, adherence to the intensity and duration of HIIT was variable and underreported, which has implications for determining the treatment effect of the exercise interventions being compared. Furthermore, additional research is needed to investigate the utility of home-based HIIT and long-term adherence to HIIT following supervised programs. This review provides recommendations for researchers in the measurement and reporting of adherence to HIIT and other exercise interventions to facilitate a sufficient and consistent approach for future studies. This article also highlights strategies for clinicians to improve adherence, feasibility, and enjoyment of HIIT for their patients.

Effect of self-tailored high-intensity interval training versus moderate-intensity continuous exercise on cardiorespiratory fitness after myocardial infarction: A randomized controlled trial

BACKGROUND

Whether high-intensity interval training (HIIT) is more efficient than moderate-intensity continuous exercise (MICE) to increase cardiorespiratory fitness in patients with acute coronary syndrome at moderate-to-high cardiovascular risk is controversial. The best approach to guide training intensity remains to be determined.

OBJECTIVE

We aimed to assess intensities achieved with self-tailored HIIT and MICE according to perceived exertion and to compare the effect on cardiorespiratory fitness in patients early after ST-elevation myocardial infarction (STEMI).

METHODS

We included 69 males starting cardiac rehabilitation within 4 weeks after STEMI. After a 3-week run-in phase with MICE, 35 patients were randomized to 9 weeks of HIIT (2×HIIT and 1×MICE per week) and 34 patients to MICE (3×MICE). Training workload for MICE was initially set at the patients' first ventilatory threshold (VT). HIIT consisted of 4×4-min intervals with a workload above the second VT in high intervals. Training intensity was adjusted weekly to maintain the perceived exertion (Borg score 13-14 for MICE, ≥15 for HIIT). Session duration was 38 min in both groups. Peak oxygen consumption (VO2) was measured by cardiopulmonary exercise testing pre- and post-intervention.

RESULTS

Both groups improved peak VO2 (ml/kg/min) (HIIT +1.9, p<0.001; MICE +3.2, p<0.001, Cohen's d -0.4), but changes in VO2 were not significantly different between groups (p=0.104). Exercise regimes did not differ between groups in terms of energy expenditure or training time, but perceived exertion was higher with HIIT.

CONCLUSIONS

Self-tailored HIIT was feasible in patients early after STEMI. It was more strenuous but not superior nor more time efficient than MICE in improving peak VO2.

A Comparison of Exercise Intensity in Hybrid Versus Standard Phase Two Cardiac Rehabilitation

PURPOSE

To compare exercise training intensity during standard cardiac rehabilitation (S-CR) versus hybrid-CR (combined clinic- and remote home-/community-based).

METHODS

The iATTEND (improving ATTENDance to cardiac rehabilitation) trial is currently enrolling subjects and randomizing patients to S-CR versus hybrid-CR. This substudy involves the first 47 subjects who completed ≥18 CR sessions. Patients in S-CR completed all visits in a typical phase II clinic-based setting and patients in hybrid-CR completed up to 17 of their sessions remotely using telehealth (TH). Exercise training intensity in both CR settings is based on heart rate (HR) data from each CR session, expressed as percent HR reserve.

RESULTS

Among patients in both study groups, there were no serious adverse events or falls that required hospitalization during or within 3 hr after completing a CR session. Expressed as a percentage of HR reserve, the overall mean exercise training intensities during both the S-CR sessions and the TH-CR sessions from hybrid-CR were not significantly different at 63 ± 12% and 65 ± 10%, respectively (P = .29).

CONCLUSION

This study showed that hybrid-CR delivered using remote TH results in exercise training intensities that are not significantly different from S-CR.

Short-term and Long-term Feasibility, Safety, and Efficacy of High-Intensity Interval Training in Cardiac Rehabilitation: The FITR Heart Study Randomized Clinical Trial

Importance

High-intensity interval training (HIIT) is recognized as a potent stimulus for improving cardiorespiratory fitness (volume of oxygen consumption [VO2] peak) in patients with coronary artery disease (CAD). However, the feasibility, safety, and long-term effects of HIIT in this population are unclear.

Objective

To compare HIIT with moderate-intensity continuous training (MICT) for feasibility, safety, adherence, and efficacy of improving VO2 peak in patients with CAD.

Design, Setting, and Participants

In this single-center randomized clinical trial, participants underwent 4 weeks of supervised training in a private hospital cardiac rehabilitation program, with subsequent home-based training and follow-up over 12 months. A total of 96 participants with angiographically proven CAD aged 18 to 80 years were enrolled, and 93 participants were medically cleared for participation following a cardiopulmonary exercise test. Data were collected from May 2016 to December 2018, and data were analyzed from December 2018 to August 2019.

Interventions

A 4 × 4-minute HIIT program or a 40-minute MICT program (usual care). Patients completed 3 sessions per week (2 supervised and 1 home-based session) for 4 weeks and 3 home-based sessions per week thereafter for 48 weeks.

Main Outcomes and Measures

The primary outcome was change in VO2 peak during the cardiopulmonary exercise test from baseline to 4 weeks. Further testing occurred at 3, 6, and 12 months. Secondary outcomes were feasibility, safety, adherence, cardiovascular risk factors, and quality of life.

Results

Of 93 randomized participants, 78 (84%) were male, the mean (SD) age was 65 (8) years, and 46 were randomized to HIIT and 47 to MICT. A total of 86 participants completed testing at 4 weeks for the primary outcome, including 43 in the HIIT group and 43 in the MICT group; 69 completed testing at 12 months for VO2 peak, including 32 in the HIIT group and 37 in the MICT group. After 4 weeks, HIIT improved VO2 peak by 10% compared with 4% in the MICT group (mean [SD] oxygen uptake: HIIT, 2.9 [3.4] mL/kg/min; MICT, 1.2 [3.4] mL/kg/min; P = .02). After 12 months, there were similar improvements from baseline between groups, with a 10% improvement in the HIIT group and a 7% improvement in the MICT group (mean [SD] oxygen uptake: HIIT, 2.9 [4.5] mL/kg/min; MICT, 1.8 [4.3] mL/kg/min; P = .30). Both groups had high feasibility scores and low rates of withdrawal due to serious adverse events (3 participants in the HIIT group and 1 participant in the MICT group). One event occurred following exercise (hypotension) in the HIIT group. Over 12 months, both home-based HIIT and MICT had low rates of adherence (HIIT, 18 of 34 [53%]; MICT, 15 of 37 [41%]; P = .35) compared with the supervised stage (HIIT, 39 of 44 [91%]; MICT, 39 of 43 [91%]; P > .99).

Conclusions and Relevance

In this randomized clinical trial, a 4-week HIIT program improved VO2 peak compared with MICT in patients with CAD attending cardiac rehabilitation. However, improvements in VO2 peak at 12 months were similar for both groups. HIIT was feasible and safe, with similar adherence to MICT over 12-month follow-up. These findings support inclusion of HIIT in cardiac rehabilitation programs as an adjunct or alternative modality to moderate-intensity exercise.

Trial Registration

Australian New Zealand Clinical Trials Registry Identifier: ACTRN12615001292561.

Are the Current Cardiac Rehabilitation Programs Optimized to Improve Cardiorespiratory Fitness in Patients? A Meta-Analysis

Previous meta-analyses have shown that high-intensity interval training (HIIT) is more suitable than moderate continuous training (MCT) for improving peak oxygen uptake (VO2peak) in patients with coronary artery disease. However, none of these meta-analyses have tried to explain the heterogeneity of the empirical studies in optimizing cardiac rehabilitation programs. Therefore, our aims were (a) to estimate the effect of MCT and HIIT on VO2peak, and (b) to find the potential moderator variables. A search was conducted in PubMed, Scopus, and ScienceDirect. Out of the 3,110 references retrieved, 29 studies fulfilled the selection criteria to be included in our meta-analysis. The mean difference was used as the effect size index. Our results showed significant enhancements in VO2peak after cardiac rehabilitation based on MCT and HIIT (mean difference = 3.23; 95% confidence interval [2.81, 3.65] ml·kg-1·min-1 and mean difference = 4.61; 95% confidence interval [4.02, 5.19] ml·kg-1·min-1, respectively), with greater increases after HIIT (p < .001). Heterogeneity analyses reached statistical significance with moderate heterogeneity for MCT (p < .001; I2 = 67.0%), whereas no heterogeneity was found for the effect of HIIT (p = .220; I2 = 22.0%). Subgroup analyses showed significant between-group heterogeneity of the MCT-induced effect based on the training mode (p < .001; I2 = 90.4%), the risk of a new event (p = .010; I2 = 77.4%), the type of cardiovascular event (p = .009; I2 = 84.8%), the wait time to start cardiac rehabilitation (p = .010; I2 = 76.6%), and participant allocation (p = .002; I2 = 89.9%). Meta-regressions revealed that the percentages of patients undergoing a revascularization procedure (B = -0.022; p = .041) and cardiorespiratory fitness at baseline (B = -0.103; p = .025) were inversely related to the MCT-induced effect on the VO2peak.

The feasibility of implementing high-intensity interval training in cardiac rehabilitation settings: a retrospective analysis

Background

Cardiovascular disease is the leading cause of death worldwide. Notwithstanding the well-known benefits of cardiac rehabilitation (CR), adherence to CR remains low, particularly in women. High-intensity interval training (HIIT) has received specific attention as an emerging exercise-training paradigm that addresses frequently cited barriers to CR (i.e. lack of motivation/enjoyment and time, perceiving exercise regime as tiring/boring) and improves cardiovascular risk factors. Previous studies have examined the safety of HIIT in CR; there is little evidence on the feasibility of HIIT in CR. The aims of this study were to evaluate the feasibility of HIIT within a CR setting and examine the sex differences regarding the feasibility of such programming.

Methods

Patients attended an on-site HIIT CR program (10-min warm-up, 25 min of interspersed high-intensity [HI - 4 min at 85–95% HRpeak] and lower intensity [LO - 3 min at 60–70% HRpeak] intervals, 10-min cool-down) twice weekly for 10 weeks. Heart rate (HR) and the Borg rating of perceived exertion (RPE) scale (6–20 points) were recorded at each session. Feasibility was assessed by: [1] attendance and compliance: the number of sessions attended and the compliance to the prescribed HI and LO HR ranges; [2] the patient experience: patients’ perceived effort, program difficulty, if the program was challenging and satisfying; and, [3] safety. Descriptive statistics were used to report the means and their variations. Mann-Whitney U tests and Chi-square analyses were performed to examine sex-differences.

Results

A total of 151 patients (33% women, 57.5 ± 9.1 years) attended the HIIT program and completed 16 ± 5 classes with a low attrition rate (11.3%). Most patients met or exceeded the prescribed target HR for the HI (80%) and LO (84%) intervals, respectively. Patients reported a “somewhat hard” RPE for HI (14 ± 2 points) and “very light” for LO (10 ± 2 points) intervals. All patients were satisfied with the program and found it challenging. Most patients found HIIT to be difficult (7 ± 2 points, scale range 0–10 points), yet safe (97%). Three vasovagal episodes occurred and more women dropped-out of the program than men (p < 0.01).

Conclusions

HIIT is a feasible, safe and well-received exercise paradigm in a CR setting.

Capturing the perspectives of women with coronary artery disease regarding interval training or continuous exercise in cardiac rehabilitation

Background: Motivators and barriers to exercise participation in women with coronary artery disease remain poorly understood. With evidence suggesting that women with coronary artery disease are less likely to adhere to exercise during cardiac rehabilitation and are more likely to drop out, it is important to understand these factors in order to optimize cardiac rehabilitation programs for women.Methods: We contribute to the discussion by presenting findings from a qualitative study using two focus groups with nine women with coronary artery disease sharing their experiences with attending cardiac rehabilitation and exercising in this setting, in addition to their perceived motivators and barriers to performing aerobic interval training. Focus group transcripts were analysed using a deductive thematic approach with Bandura's Social Cognitive Theory as the guiding conceptual framework.Results: Four themes were identified regarding the attitudes and experiences of attending and exercising at cardiac rehabilitation, while five themes capturing the motivators and barriers for these women to perform aerobic interval training were identified for the first time. These novel themes encompassed the daunting nature of it, the physical discomfort associated with it, and conversely, the potential sense of enjoyment and accomplishment that it could bring.Conclusion: This study demonstrates the complexity of implementation of aerobic interval training into clinical practice, and suggests that further research is warranted to explore this domain.IMPLICATIONS FOR REHABILITATIONDespite challenges in feasibility of conducting a randomised controlled trial in female patients with coronary artery disease examining the effects of aerobic interval training versus moderate-intensity continuous exercise on aerobic exercise capacity, there was a significant per protocol treatment effect of 0.95 ml·kg^-1·min^-1 in favour of aerobic interval training.The cardiac rehabilitation environment provides key facilitators and perceived benefits for exercising and attending cardiac rehabilitation for women, and thus emphasises the need for improving referral and enrolment processes specifically for women into cardiac rehabilitation programs.Aerobic interval training may elicit feelings of fear and physical discomfort, or may be precluded by comorbid conditions, therefore, judicious consideration must be taken in examining the suitability of implementation into clinical practice for each female patient.

Exercise Prescription Guidelines for Cardiovascular Disease Patients in the Absence of a Baseline Stress Test

Aerobic exercise is a core component of cardiac rehabilitation (CR). Leading organizations recommend that the exercise prescriptions should be based on a symptom limited baseline graded exercise test (GXT). However, recent evidence suggests that only ~30% of CR clinics perform baseline GXTs. Consequently, exercise prescriptions including exercise progression in CR are not following standard exercise prescription guidelines. Therefore, the purpose of this review is to provide clinicians with evidence-based techniques for prescribing exercise in the absence of a baseline GXT. Intensity indicators (e.g., heart rate, perceived exertion) are reviewed, along with special exercise considerations for various disease states (e.g., heart failure, peripheral artery disease, and coronary artery disease). Baseline exercise testing remains the gold standard approach for prescribing exercise among heart disease patients, however, clinicians must be prepared to safely develop and monitor patients when a baseline GXT is not performed.

Exercise Recommendations for the Athlete With Coronary Artery Disease

PURPOSE OF THE REVIEW

We provide a framework for formulating exercise prescriptions for those with CAD in order to achieve the "optimal" dose of exercise for each individual.

RECENT FINDINGS

Multiple epidemiological studies demonstrate that exercise is inversely associated with atherosclerotic coronary artery disease (CAD), yet the risk of an acute coronary event is transiently elevated during vigorous exercise. In turn, CAD is the most common cause of exercise-related sudden cardiac death (SCD) in older athletes. When prescribing exercise recommendations for athletes with CAD, we should maintain equipoise between the benefits derived from sports participation and the risk of an adverse cardiac event. Athletes are not immune from atherosclerotic CAD, and we should perform risk assessments regardless of physical and athletic prowess. Cardiopulmonary exercise testing may be a useful tool to develop individualized exercise regimens for athletes with CAD.