The effectiveness of three months of aerobic exercise in increasing exercise capacity was studied in past-surgical peripheral arterial occlusive disease (PAOD) patients. Seven post-surgical PAOD patients (3 to 36 months post-percutaneous transluminal angioplasty or percutaneous transluminal laser angioplasty) currently experiencing mild to moderate claudication pain with exertion were exercised for twelve weeks on either a treadmill or a stairclimbing machine. Prior to entry into the exercise program the patients were given exercise tests on both the treadmill and the stairclimbing machine. The tests included a progressive exercise test and a single stage exercise test on both the treadmill and the stairclimbing machine. Maximal pain free exercise time (MPFXT) and maximal exercise time (MXT) were recorded for each exercise test. Additionally, the ankle systolic blood pressure and the brachial systolic blood pressure were recorded to determine the ankle brachial index (ABI) prior to and for several minutes after each test. Transcutaneous oxygen tension (TCPO2) was also measured prior to and for several minutes after each test. Additionally a lipid analysis was performed on each subject prior to and following the exercise program. Body composition was recorded on each subject before and after the exercise regime. All tests were repeated at the end of the training period. There was a significant increase from 139.4 to 228.4 seconds in MPFXT on the single stage stairclimbing test (p < 0.01), and on the progressive treadmill test from 175.3 to 203.8 seconds (p < 0.05). On the other tests for MPFXT the increases failed to achieve significance. There was a significant increase in the MXT on the single stage stairclimbing test, from 274.0 to 552.7 seconds as well as on the progressive stairclimbing test, from 391.4 to 490.3 seconds (p < 0.05 for both tests). On the treadmill posttests the increases in MXT failed to achieve significance. There were no significant differences found in the ABIs, TCPO2 measurements, lipid profiles or body compositions of subjects after the exercise trial. While it appears that three months exercise training will enhance the ability of post-surgical PAOD patients suffering from intermittent claudication to walk or perform on a stairclimbing machine, the hemodynamic variables studied did not significantly improve following the exercise trial, nor did the patients' body compositions alter.