A randomized control trial (RCT) is planned to evaluate a web-based intervention (CardioFit) against usual care in increasing physical activity levels in patients with Coronary Artery Disease (CAD). We hypothesize that compared to usual care, participants in CardioFit will; a) have increased physical activity levels, b) will have a higher health-related quality of life at measurement dates and, c) will have greater improvements in psychosocial predictors.

Most existing cardiac rehabilitation programs have little ability to expand participation using traditional delivery models that emphasize supervised, facility-based programs. Futhermore, facility based programs to promote physical activity behavior in patients with coronary artery disease (CAD) are limited in their impact because most patients are unwilling to travel more than 30-40 minutes to participate in a program. CardioFit is an off-site, 26 week web-based physical activity coaching service for people with heart disease. Within the CardioFit program, patients will be assigned to an on-line "coach" and receive customized exercise programs based on their medical history, personal goals and preferences. A randomized control trial (RCT) is planned to evaluate the effectiveness of the web-based intervention at increasing physical activity levels against usual care in patients with CAD.

This study is in the third phase of a three-phase research program to examine interventions to promote physical activity for the secondary prevention of Cardiovascular disease.

Inclusion Criteria:

• Age 20 to 80 years
• English Proficiency
• Internet Access (home or work)
• Documented CAD (most recent cardiac diagnosis); documented Myocardial Infarction (MI), successful PCI procedure

Exclusion Criteria:

• Patient intends to enroll in structured cardiac rehabilitation
• Hospitalization for Coronary Artery Bypass (CABG)
• Hospitalization for diagnostic procedure not associated with previously documented MI
• Patient coming back to hospital for planned staged PCI within 6 months
• Cardiac transplantation
• Presence of, or hospitalization for defibrillator implant
• Hospitalization for pacemaker implantation
• Unresolved unstable angina &/or hospitalization for angina (without MI or PCI)
• Uncontrolled arrhythmias causing symptoms or hemodynamic compromise
• Neuromuscular, musculoskeletal or rheumatoid disorders that are exacerbated by exercise
• Other uncontrolled metabolic conditions (e.g. diabetes)
• Chronic infectious diseases such as mononucleosis, hepatitis, AIDS
• Acute systematic illness or fever
• Uncontrolled tachycardia (<120 bpm)
• Uncompensated congestive heart failure (&/or NYHA Class III, or IV)
• 3rd degree AV block without pacemaker
• Active pericarditis or myocarditis
• Recent embolism
• Suspected or known AAA aneurysm > 4cm
• Uncontrolled hypertension (SBP > 200; DBP > 110)
• Pregnancy

Baseline to 12 months

• measurement of physical activity may have made patients more aware of their physical activity, increasing it above their normal habits. To mitigate this, data from the first and ninth day were removed from the analysis.
• greater attrition rate than in previous similar studies.
• the generalizability of the results may have been affected due to the high education of the participants and the low number of female participants.
• exercise was not observed, so may have been exaggerated.

The Research Assistants conducting the follow-up assessments were blinded to the participant's treatment allocation.