Introduction Frailty is a geriatric syndrome characterised by reductions in muscle mass, strength, endurance and activity level. The frailty syndrome, prevalent in 25–50% of patients undergoing cardiac surgery, is associated with increased rates of mortality and major morbidity as well as function decline postoperatively. This trial will compare a preoperative, interdisciplinary exercise and health promotion intervention to current standard of care (StanC) for elective coronary artery bypass and valvular surgery patients for the purpose of determining if the intervention improves 3-month and 12-month clinical outcomes among a population of frail patients waiting for elective cardiac surgery.

Methods and analysis This is a multicentre, randomised, open end point, controlled trial using assessor blinding and intent-to-treat analysis. Two-hundred and forty-four elective cardiac surgical patients will be recruited and randomised to receive either StanC or StanC plus an 8-week exercise and education intervention at a certified medical fitness facility. Patients will attend two weekly sessions and aerobic exercise will be prescribed at 40–60% of heart rate reserve. Data collection will occur at baseline, 1–2 weeks preoperatively, and at 3 and 12 months postoperatively. The primary outcome of the trial will be the proportion of patients requiring a hospital length of stay greater than 7 days.

Potential impact of study The healthcare team is faced with an increasingly complex older adult patient population. As such, this trial aims to provide novel evidence supporting a health intervention to ensure that frail, older adult patients thrive after undergoing cardiac surgery.

Ethics and dissemination Trial results will be published in peer-reviewed journals, and presented at national and international scientific meetings. The University of Manitoba Health Research Ethics Board has approved the study protocol V.1.3, dated 11 August 2014 (H2014:208).

Trial registration number The trial has been registered on ClinicalTrials.gov, a registry and results database of privately and publicly funded clinical studies (NCT02219815).