In Spain, family physician are currently recommended to prescribe an unsupervised walking program to their coronary heart disease (CHD) patients as a part of their cardiac rehabilitation program. However, there are a few family physicians who provide their CHD patients with supervised exercise (30 minutes of pedaling on an stationary bicycle at 60-85% of the peak heart rate (HR) attained at the maximal or symptom limited treadmill test, 3 times a week) at their primary care health centers, thinking that these patients improve their functional capacity, quality of life, and the control of cardiovascular risk factors, more than walking because they can not achieve the ideal exercise intensity for maximal benefits by walking. This study has been designed to investigate if CHD patients get more health benefits with the supervised exercise program at the health center than with the unsupervised walking program.