Background: In the United Kingdom (UK), exercise intensity is prescribed from a fixed percentage range (% heart rate reserve (%HRR)) in cardiac rehabilitation programmes. We aimed to determine the accuracy of this approach by comparing it with an objective, threshold-based approach incorporating the accurate determination of ventilatory anaerobic threshold (VAT). We also aimed to investigate the role of baseline cardiorespiratory fitness status and exercise testing mode dependency (cycle vs. treadmill ergometer) on these relationships. Design and methods: A maximal cardiopulmonary exercise test was conducted on a cycle ergometer or a treadmill before and following usual-care circuit training from two separate cardiac rehabilitation programmes from a single region in the UK. The heart rate corresponding to VAT was compared with current heart rate-based exercise prescription guidelines. Results: We included 112 referred patients (61 years (59–63); body mass index 29 kg·m^–2 (29–30); 88% male). There was a significant but relatively weak correlation ( r = 0.32; p = 0.001) between measured and predicted %HRR, and values were significantly different from each other ( p = 0.005). Within this cohort, we found that 55% of patients had their VAT identified outside of the 40–70% predicted HRR exercise training zone. In the majority of participants (45%), the VAT occurred at an exercise intensity <40% HRR. Moreover, 57% of patients with low levels of cardiorespiratory fitness achieved VAT at 70% HRR. VAT was significantly higher on the treadmill than the cycle ergometer ( p < 0.001). Conclusion: In the UK, current guidelines for prescribing exercise intensity are based on a fixed percentage range. Our findings indicate that this approach may be inaccurate in a large proportion of patients undertaking cardiac rehabilitation.

Background: There is wide discrepancy in how published research defines and reports home-based exercise programmes. Studies consisting of fundamentally different designs have been labelled as home-based, making searching for relevant literature challenging and time consuming. This issue has been further highlighted by an increased demand for these programmes following the COVID-19 pandemic and associated government-imposed lockdowns. Purpose: To examine what specifically constitutes home-based exercise by: (1) developing definitions for a range of terms used when reporting exercise and physical activity programmes and (2) providing examples to contextualise these definitions for use when reporting exercise and physical activity programmes. Methods: A literature search was undertaken to identify previous attempts to define home-based exercise programmes. A working document, including initial definitions and examples were developed, which were then discussed between six experts for further refinement. Results: We generated definitions for universal key terms within three domains (and subdomains) of programme design: location (home-based, community/centre-based, or clinical setting), prescription (structured or unstructured) and delivery (supervised, facilitated, or unsupervised). Examples for possible combinations of design terms were produced. Conclusions: Definitions will provide consistency when using reporting tools and the intention is to discuss the issues presented as part of a Delphi study. This is of paramount importance due to the predicted increase in emerging research regarding home-based exercise.

Introduction: Current international guidelines for cardiac rehabilitation (CR) advocate moderate-intensity exercise training (MISS, moderate-intensity steady state). This recommendation predates significant advances in medical therapy for coronary heart disease (CHD) and may not be the most appropriate strategy for the ‘modern’ patient with CHD. High-intensity interval training (HIIT) appears to be a safe and effective alternative, resulting in greater improvements in peak oxygen uptake (VO_{2 peak}). To date, HIIT trials have predominantly been proof-of-concept studies in the laboratory setting and conducted outside the UK. The purpose of this multicentre randomised controlled trial is to compare the effects of HIIT and MISS training in patients with CHD attending UK CR programmes. Methods and analysis: This pragmatic study will randomly allocate 510 patients with CHD to 8 weeks of twice weekly HIIT or MISS training at 3 centres in the UK. HIIT will consist of 10 high-intensity (85–90% peak power output (PPO)) and 10 low-intensity (20–25% PPO) intervals, each lasting 1 min. MISS training will follow usual care recommendations, adhering to currently accepted UK guidelines (ie, >20 min continuous exercise at 40–70% heart rate reserve). Outcome measures will be assessed at baseline, 8 weeks and 12 months. The primary outcome for the trial will be change in VO_{2 peak} as determined by maximal cardiopulmonary exercise testing. Secondary measures will assess physiological, psychosocial and economic outcomes. Ethics and dissemination: The study protocol V.1.0, dated 1 February 2016, was approved by the NHS Health Research Authority, East Midlands—Leicester South Research Ethics Committee (16/EM/0079). Recruitment will start in August 2016 and will be completed in June 2018. Results will be published in peer-reviewed journals, presented at national and international scientific meetings and are expected to inform future national guidelines for exercise training in UK CR. Trial registration number: NCT02784873; pre-results.

Recent evidence suggests that routine exercise-based cardiac rehabilitation (CR) may not lead to a substantial increase in estimated peak oxygen uptake (V̇O2peak). This could reduce the potential benefits of CR and explain why CR no longer improves patient survival in recent studies. We aimed to determine whether routine exercise-based CR increases V̇O2peak using gold-standard maximal cardiopulmonary exercise testing (CPET), and to quantify the exercise training stimulus which might be insufficient in patients undertaking CR. We studied the effects of a routine, twice weekly, exercise-based CR programme for eight weeks (intervention group) compared with abstention from supervised exercise training (control group) in patients with coronary heart disease. The primary outcome was V̇O2peak measured using CPET. We also measured changes in body composition using dual X-ray absorptiometry, carotid intima-media thickness, hs-CRP and N-terminal pro B-type natriuretic peptide at baseline, 10 weeks and 12 months. We also calculated the Calibre 5-year all-cause mortality risk score. Seventy patients (age 63.1 SD10.0 years; BMI 29.2 SD4.0 kg·m-2; 86% male) were recruited (n = 48 intervention; n = 22 controls). The mean aerobic exercise training duration was 23 min per training session, and the mean exercise training intensity was 45.9% of heart rate reserve. V̇O2peak was 23·3 ml·kg-1·min-1 at baseline, and there were no changes in V̇O2peak between groups at any time point. The intervention had no effect on any of the secondary endpoints. Routine CR does not lead to an increase in V̇O2peak and is unlikely to improve long-term physiological outcomes.

Intermittent claudication (IC) is a classic symptom of peripheral artery disease, with first line treatment being supervised exercise therapy (SET). Despite this, SET is frequently underutilised, and adherence is often poor. An alternative option are home-based exercise programmes (HBEP). Although HBEPs are well tolerated, to the authors’ knowledge, no research has assessed their safety. The aim of this review was to assess the safety of HBEPs in people living with IC. We performed an electronic search of the MEDLINE, CINAHL, and Cochrane Library databases. The main parameter of interest was complication rate, calculated as the number of related adverse events per patient-hours. Subanalysis was undertaken to determine differences in safety for studies that did and did not include pre-exercise cardiac screening, and for studies with exercise at low, moderate, and high levels of claudication pain. Our search strategy identified 8693 results, of which 27 studies were included for full review. Studies included 1642 participants completing 147,810 patient-hours of home-based exercise. Four related adverse events were reported, three of which were cardiac in origin, giving an all-cause complication rate of one event per 36,953 patient-hours. Three of these events occurred following exercise to high levels of claudication pain, and one occurred with pain-free exercise. One event occured in a study without cardiac screening. Based on the low number of related adverse events, HBEPs appear to be a safe method of exercise prescription for people with IC. Our results strengthen the rationale for providing alternative exercise options for this population. PROSPERO Registration No.: CRD42021254581