The Renal Exercise Demonstration Project provided two different approaches to exercise programming to a group of hemodialysis patients. Physical functioning and self-reported health-related quality of life were measured at baseline, after 2 months of independent exercise, and again after 2 months of in-center cycling. This study compares the responses to intervention of patients who initially scored low (<34) on the Physical Component Scale (PCS) on the Medical Outcomes Study Short-Form 36 questionnaire to those who initially scored higher (>34) on the same scale. The high-PCS group scored higher on all physical function tests (normal gait speed, fast gait speed, and sit-to-stand test) at each testing time than the low-PCS group. The high-PCS group improved only on the sit-to-stand test, whereas the low-PCS group improved in all three physical function tests. There were significant differences between the groups in change over time in all the physical scales and the PCS over time, with the low-PCS group showing improvements in response to the intervention and the high-PCS group showing no change over time. No differences in change over time were noted between the groups on the mental scales in either group. We conclude that low-functioning hemodialysis patients can benefit from exercise counseling in both objective measures of physical functioning and self-reported physical functioning. The impact of such interventions seems to be more profound in the lowest functioning patients.