Stress is associated with many health maladies, including cancers. Exercise is an effective stress-management tool and is important for physical health. The number of Hispanic women who engage in enough exercise is low. Thus, promoting exercise for this population is of critical importance. Individual effectiveness of behavioral interventions can often be lost in group analyses. Therefore, we employed both group analyses and single-system methodology to test the effectiveness of an exercise program for 25 Hispanic breast cancer survivors. Measures of physical fitness, quality of life, self-reported stress, and salivary cortisol were taken repeatedly before, during, and after the intervention. The intervention improved physical fitness, reduced perceived stress, and decreased cortisol levels as evidenced by both group and single-system analyses.