An Evaluation of the Talk Test for Exercise Prescription for Home-Based Cardiac Rehabilitation (Talk-Test)

An Evaluation of the Talk Test as an Effective and Safe Approach for Exercise Prescription for Home-Based Cardiac Rehabilitation: A Pilot RCT

The objectives of this pilot RCT are to examine if the Talk Test is an effective and safe tool as compared with CPET for exercise prescription in patients who have undergone CABG or PCI and enrolled in a home-based CR program with virtual exercise training monitoring.

The Talk Test has been shown to be a valid, practical and inexpensive tool for guiding exercise training in patients with CAD. The general premise of the Talk Test is that exercising at or above the ventilatory threshold or lactate threshold does not allow comfortable, conversational speech and thus serves as a means of estimating the cut point between moderate and vigorous intensity exercise. The Talk Test can be used to produce exercise intensities (64 to 95% HR peak i.e. moderate-to-vigorous intensity exercise) within accepted Canadian Association of Cardiovascular Prevention and Rehabilitation (CACPR) guidelines for exercise training, to avoid exertional ischemia, and has been shown to be consistent across various modes of exercise (i.e. walking, jogging, cycling, elliptical trainer and stair stepper). There is a critical need to evaluate the effectiveness and safety of using the Talk Test as the principal method of exercise prescription in patients with CAD who have undergone CABG or PCI when compared to standard care CPET. Such a trial has wide-scale appeal for CR programs across Canada and beyond. It will directly and positively impact patient care by reducing the need for in-person interactions for CPET, of paramount importance during COVID-19 outbreaks, between patients and CR staff, thus reducing COVID-19 infection risk and concerns of contracting the virus.

Participants will be enrolled in the virtual cardiac rehab program and receive an exercise prescription based on the Talk test method.

Participants will be enrolled in the virtual cardiac rehab program and receive an exercise prescription based on their CPET results completed at baseline

meticulously track all mild, moderate, and severe symptoms and adverse events throughout this study. Symptoms may include tightness in chest, leg tightness/pain, dizziness, lightheaded, foot cramping, and heart palpitations.

will be measured using a gold standard symptom-limited CPET on an electronically braked cycle ergometer (alternatively it will be administered on a treadmill or another aerobic equipment). Gas exchange (VO2 in mL/kg/min) and heart rate will be monitored continuously. The highest 20-s interval average of VO2 and HR will be considered the peak VO2 and HR values.

Talk Test group: HR will be measured during exercise training using the Polar A370 device. Following each exercise session, participants will record on a Talk Test log if: (1) singing was possible, (2) comfortable conversation, but not singing was possible, or (3) comfortable conversation was not possible. These responses will be coded as "does not comply", "complies" and "exceeds". CPET group: HR will be measured during exercise training using the Polar A370 device. Where participants exercise below, within or above the prescribed HR ranges (64 to 95% HR peak), they will be coded as "does not comply", "complies" and "exceeds". All participants will wear Polar A370 devices during their exercise training sessions. Exercise HRs will be compared between the Talk Test and CPET groups.

Body composition will be measured using Fat mass (%) and fat-free mass (%), using bioelectrical impedance analysis.

Resting Systolic (mmHg) and Diastolic (mmHg) blood pressure will be measured in a seated position after a 5-minute rest period on the right arm using an automated, BP monitor (BPTru) that measures 6 times (the first will be discarded and an average of the last 5 measurements will be used for statistical analyses) at 2-minute intervals.

Inclusion Criteria: recently underwent PCI or CABG (at least 4 weeks but less than 12 weeks post-event or procedure); able to perform a CPET; at least 40 years of age; access to MyChart; and, access to email and the internet access to a cellphone with broadband internet (4G, LTE, 5G). Exclusion Criteria: currently participating in a virtual or on-site CR program; ventricular ejection fraction ≤45%; unstable angina or established diagnosis of chronic obstructive pulmonary disease, severe mitral or aortic stenosis, or hypertrophic obstructive cardiomyopathy; unable to return for 12-week follow-up visits.