Treadmill testing. Subjects were tested on a
graded treadmill protocol on entry and after 12 and
24 weeks. After a familiarization treadmill test was
performed during the initial visit, a second test on
another day was used for data analysis. Subjects
walked on the treadmill at an initial workload of 2
mph, 0% grade for 3 minutes. Subsequent stages
increased 3.5% in grade every 3 minutes (with no
change in speed) to maximal claudication pain as
previously described. 3a9 During exercise, heart rate
(by 12-lead EKG) and arm blood pressure were
monitored every minute. The change in the severity
of claudication pain experienced by the patient was
recorded on a scale of 1 to 5 with 1 = no pain,
2 = onset claudication, 3 = mild, 4 = moderate,
and 5 -- severe pain. All subjects reached a maximal
level of claudication pain that limited exercise during
the graded treadmill test.