Walking is the most common aerobic training modality utilized in cardiac rehabilitation programs. However, it remains unclear whether or not brisk walking is of a sufficient intensity to improve aerobic fitness in this population. In this study, we investigated whether men and women with coronary artery disease can achieve an exercise intensity that is sufficient to induce a training effect, ie, a training heart rate (THR), defined as ≥ 70% of measured maximal heart rate (HRmax), via brisk walking on a flat surface. One hundred forty-two outpatient volunteers from the William Beaumont Hospital Cardiac Rehabilitation Program (Royal Oak, MI) and the University of Wisconsin-La Crosse Exercise and Health Program (La Crosse, WI) were asked to walk one mile as briskly as possible on measured tracks. Heart rate was monitored throughout the walk via radiotelemetry. The percentage of patients within each gender and phase of rehabilitation who attained a THR were assessed using peak or symptom-limited exercise testing to determine the HRmax. All of the women and 90% of the men achieved a THR, averaging 85 ± 8% and 79 ± 10% of HRmax, respectively (mean ± SD). There was no difference in the percentage of phase II or phase III cardiac rehabilitation program patients who achieved a THR. These findings suggest that brisk walking is of a sufficient intensity to elicit a THR in all but the most highly fit patients with coronary disease. Thus, physicians and allied health professionals can prescribe brisk walking on a flat surface to their cardiac patients with confidence that this intensity will achieve cardiorespiratory and health benefits.