Estimated peak functional capacity: an accurate method for assessing change in peak oxygen consumption after cardiac rehabilitation?

Calculation of Oxygen Uptake during Ambulatory Cardiac Rehabilitation

Background: Cardiopulmonary exercise testing is not used routinely. The goal of this study was to determine whether accurate estimates of VO2 values can be made at the beginning and at the end of a rehabilitation program. Methods: A total of 91 cardiac rehabilitation patients were included. Each participant had to complete cardiopulmonary exercise testing at the beginning and at the end of a rehabilitation program. Measured VO2 values were compared with estimates based on three different equations. Results: Analyses of the means of the differences in the peak values showed very good agreement between the results obtained with the FRIEND equation or those obtained with a combination of rules of thumb and the results of the measurements. This agreement was confirmed with the ICCs and with the standard errors of the measurements. The ACSM equation performed worse. The same tendency was seen when considering the VO2 values at percentage-derived work rates. Conclusions: The FRIEND equation and the more easily applicable combination of rules of thumb are suitable for estimating the peak VO2 and the VO2 at a percentage-derived work rate in cardiac patients both at the beginning and at the end of a cardiac rehabilitation program.

Eight-week equipment-based Pilates exercises positively affects quality of life, and functional capacity in non-active adult women: a randomized controlled trial

BACKGROUND

The Pilates exercises are popular for muscle conditioning among women. However, the effects on conditioning of healthy non-active adult women due to Pilates practicing are not fully explained. The aim of this randomized controlled trial was to assess the effects of equipment-based Pilates exercises on the percentage of body fat, weight, body mass index (BMI), functional capacity, and quality of life of adult healthy women.

METHODS

Seventy-eight non-active women were randomly assigned to 2 groups (Pilates or Control). The Pilates group performed a total of 16 exercise sessions (60 minutes each, performed twice a week for 8 consecutive weeks). The control group was instructed to perform no exercise. Percentage of body fat (DXA scans), weight, BMI, distance covered in the incremental shuttle walk test, maximal oxygen uptake (VO<inf>2max</inf>), and quality of life (SF-36 scores) were analyzed.

RESULTS

There were no significant between-group differences at baseline, but significant group-by-time interaction was observed for Pilates group postintervention. Higher distance covered (P=0.01), VO<inf>2max</inf> (P=0.04), and quality of life (P=0.04) were observed after the intervention compared to the control group. No differences were observed for body composition.

CONCLUSIONS

Two months of equipment-based Pilates training improved functional capacity and quality of life in healthy adult women.

Characterising the application of the "progressive overload" principle of exercise training within cardiac rehabilitation: A United Kingdom-based community programme

Background

Recent concerns have cast doubt over the effectiveness of cardiac rehabilitation [CR] programmes for improving cardiorespiratory fitness [CRF] in patients with a history of cardiac disease in the United Kingdom [UK]. We aimed to characterise the weekly progression of exercise training dose over an 8-week Phase III CR programme as we felt this may be partly responsible for the lack of improvement in CRF reported in previous studies.

Design

Observational study.

Methods

We evaluated a community-based Phase III CR programme in the UK. During each training session, patients wore an Apple Watch and the weekly progression of exercise training dose/load was quantified. The analysis was based on 332 individual training sessions. Exercise intensity [% heart rate reserve] during the cardiovascular [CV] exercise training component [%HRR-CV], CV training duration; estimated changes in cardiorespiratory fitness [change in estimated metabolic equivalents (METs)]; session rating of perceived exertion [sRPE], sRPE training load [sRPE-TL], and exercise training impulse [TRIMP] were evaluated.

Results

Thirty cardiac patients [83% male; age [SD] 67.0 [10.0] years; body mass index [SD] 28.3 [4.6] kg∙m^-2] were recruited to an 8-week programme [16 sessions in total]. Bayesian repeated-measures ANOVA indicated anecdotal evidence for the alternative hypothesis for changes in %HRR-CV (BF₁₀ = 0.61), sRPE (BF₁₀ = 1.1), and change in estimated METs (BF₁₀ = 1.2) during CR. Conversely, Bayesian repeated-measures ANOVA showed extreme evidence for changes in CV training duration (BF₁₀ = 2.438e+26), TRIMP (BF₁₀ = 71436), and sRPE-TL (BF₁₀ = 779570).

Conclusion

The key exercise training principle of progressive overload was only partially applied. Increases observed in exercise dose were due to increases in the duration of CV training, rather than combined with increases in exercise intensity [%HRR-CV and sRPE]. Accordingly, allied health professionals must ensure that exercise intensity is more consistently progressed to optimise the exercise stimulus and improvements in CRF and patient outcomes.

Current Insights into Exercise-based Cardiac Rehabilitation in Patients with Coronary Heart Disease and Chronic Heart Failure

Cardiac rehabilitation is a package of lifestyle secondary prevention strategies designed for patients with coronary heart disease and chronic heart failure. A community-based cardiac rehabilitation programme provides patients with a structured exercise training intervention alongside educational support and psychological counselling. This review provides an update regarding the clinical benefits of community-based cardiac rehabilitation from a psycho-physiological perspective, and also focuses on the latest epidemiological evidence regarding potential survival benefits. Behaviour change is key to long-term adoption of a healthy and active lifestyle following a cardiac event. In order for lifestyle interventions such as structured exercise interventions to be adopted by patients, practitioners need to ensure that behaviour change programmes are mapped against patient's priorities and values, and adapted to their level of readiness and intention to engage with the target behaviour. We review the evidence regarding behaviour change strategies for cardiac patients and provide practitioners with the latest guidance. The 'dose' of exercise training delivered to patients attending exercise-based cardiac rehabilitation is an important consideration because an improvement in peak oxygen uptake requires an adequate physiological stimulus to invoke positive physiological adaptation. We conclude by critically reviewing the latest evidence regarding exercise dose for cardiac patients including the role of traditional and more contemporary training interventions including high intensity interval training.

Does exercise prescription based on estimated heart rate training zones exceed the ventilatory anaerobic threshold in patients with coronary heart disease undergoing usual-care cardiovascular rehabilitation? A United Kingdom perspective

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 <40% HRR, whereas 30% of patients with higher fitness achieved their 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.

Is Cardiorespiratory Fitness Related to Cardiometabolic Health and All-Cause Mortality Risk in Patients with Coronary Heart Disease? A CARE CR Study

Background

Higher cardiorespiratory fitness (CRF) is associated with lower morbidity and mortality in patients with coronary heart disease (CHD). The mechanisms for this are not fully understood. A more favourable cardiometabolic risk factor profile may be responsible; however, few studies have comprehensively evaluated cardiometabolic risk factors in relation to CRF amongst patients with CHD. We aimed to explore differences in cardiometabolic risk and 5-year all-cause mortality risk in patients with CHD who have low, moderate, and high levels of CRF.

Methods

Patients with CHD underwent maximal cardiopulmonary exercise testing, echocardiogram, carotid intima-media thickness measurement, spirometry, and dual X-ray absorptiometry assessment. Full blood count, biochemical lipid profiles, high-sensitivity (hs) C-reactive protein, and NT-proBNP were analysed. Patients were defined as having low, moderate, or high CRF based on established prognostic thresholds.

Results

Seventy patients with CHD (age 63.1 ± 10.0 years, 86% male) were recruited. Patients with low CRF had a lower ventilatory anaerobic threshold, peak oxygen pulse, post-exercise heart rate recovery, and poor ventilatory efficiency. The low CRF group also had higher NT pro-BNP, hs-CRP, non-fasting glucose concentrations, and lower haemoglobin and haematocrit. Five-year mortality risk (CALIBER risk score) was also greatest in the lowest CRF group (14.9%).

Conclusions

Practitioners should interpret low CRF as an important clinical risk factor associated with adverse cardiometabolic health and poor prognosis, study registry; www.researchregistry.com.

CARE CR-Cardiovascular and cardiorespiratory Adaptations to Routine Exercise-based Cardiac Rehabilitation: a study protocol for a community-based controlled study with criterion methods

INTRODUCTION

Cardiac rehabilitation (CR) reduces all-cause and cardiovascular mortality in patients with coronary heart disease (CHD). Much of this improvement has been attributed to the beneficial effects of structured exercise training. However, UK-based studies have not confirmed this. Improvements in survival and cardiovascular health are associated with concurrent improvements in cardiorespiratory fitness (CRF). It is therefore concerning that estimated CRF improvements resulting from UK-based CR are approximately one-third of those reported in international literature. Modest improvements in CRF suggest that UK CR exercise training programmes may require optimisation if long-term survival is to be improved. However, contemporary UK studies lack control data or use estimates of CRF change. Cardiovascular and cardiorespiratory Adaptations to Routine Exercise-based CR is a longitudinal, observational, controlled study designed to assess the short-term and long-term effect of CR on CRF, as well cardiovascular and cardiometabolic health.

METHODS AND ANALYSIS

Patients will be recruited following referral to their local CR programme and will either participate in a routine, low-to-moderate intensity, 8-week (16 sessions) exercise-based CR programme or freely abstain from supervised exercise. Initial assessment will be conducted prior to exercise training, or approximately 2 weeks after referral to CR if exercise training is declined. Reassessment will coincide with completion of exercise training or 10 weeks after initial assessment for control participants. Participants will receive a final follow-up 12 months after recruitment. The primary outcome will be peak oxygen consumption determined using maximal cardiopulmonary exercise testing. Secondary outcomes will include changes in subclinical atherosclerosis (carotid intima-media thickness and plaque characteristics), body composition (dual X-ray absorptiometry) and cardiometabolic biomarkers.

ETHICS AND DISSEMINATION

Ethical approval for this non-randomised controlled study has been obtained from the Humber Bridge NHS Research Ethics Committee-Yorkshire and the Humber on the 27th September 2013, (12/YH/0278). Results will be presented at national conferences and published in peer-reviewed journals.