The effectiveness of cardiac education and visual biofeedback of heart rate as a training procedure to teach people to control their heart rate to a psychological stressor was investigated with 36 students, half of whom acted as control subjects. Training took 5 weeks and consisted of 30-min per week of awareness training, plus exercises to increase and decrease heart rate under rest and stressful conditions, with monetary rewards for success. Effects were tested by pre-post test comparisons between the control and the experimental groups, and results indicated that the group which received training significantly lowered its heart rate reactivity even though not specifically instructed to do so. However, when instructed to control heart rate reactivity for a monetary reward, the control group also succeeded at this task, raising several issues regarding the efficacy of reactivity training.