Patients with peripheral artery disease have decreased blood flow to exercising muscle causing pain. This decreased blood flow to the muscle affects the level of acylcarnitines which in turn decreases the level of carnitine. Carnitine allows muscles to function properly. This study will test the safety and efficacy of Propionyl-L-Carnitine taken in combination with a monitored exercise training program.

To test the hypothesis that Propionyl-L-Carnitine taken in combination with monitored exercise training may improve exercise performance the study will randomize male or female adults with peripheral artery disease and claudication to receive either Proprionyl-L-Carnitine or Placebo.

Inclusion Criteria:

• Ambulatory outpatient who are able to exercise
• Intermittent claudication due to peripheral artery disease
• Willingness to participate in a monitored exercise training program

Exclusion Criteria:

• Pain at rest, ischemic ulcerations, gangrene of the lower extremity
• Peripheral Artery Disease of a non-atherosclerotic nature
• Any disease process other than PAD, that may interfere with performance during the treadmill test or prevent the subject from reaching their claudication-limited PWT
• Current participation in an exercise training program or previous participtation in a monitored exercise training program within 6 months of the screening visit.