Home-based vs. Supervised Exercise for People With Claudication

• Change in walking efficiency [ Time Frame: 3 months ] [ Designated as safety issue: No ]
• Change in calf muscle circulation and calf muscle oxygen [ Time Frame: 3 months ] [ Designated as safety issue: No ]
• Change in health-related quality of life [ Time Frame: 3 months ] [ Designated as safety issue: No ]

The purpose of this study is to examine the effects of a home-based exercise rehabilitation program compared to a supervised exercise program on intermittent claudication (leg pain or discomfort) and ambulatory function.

This study seeks to 1) compare the changes in ambulatory function, vascular function, and health-related quality of life in patients limited by intermittent claudication following a home-based exercise rehabilitation program, a supervised exercise program, and a light resistance training exercise program; and 2) determine whether changes in walking efficiency, calf muscle circulation, and calf muscle oxygen are the reasons by which both home-based and supervised exercise rehabilitation improve ambulatory function.

We hypothesize that a home-based exercise program utilizing new physical activity monitoring technology that can accurately quantify exercise adherence as well as the intensity, duration, and volume of exercise sessions will result in similar changes in ambulatory function, vascular function, and health-related quality of life compared to a standard, supervised exercise program. Further, both the home-based and supervised exercise rehabilitation programs will result in greater changes in ambulatory function, vascular function, and health-related quality of life than a light resistance training exercise program. Finally, we hypothesize that the changes in walking efficiency, calf muscle circulation, and calf muscle oxygen will each be predictive of improved ambulation following the home-based exercise program as well as the supervised exercise program.

The 3-month program will consist of walking 3 times per week, with progressive increases in duration and intensity. The two walking exercise programs will be matched on the estimated caloric expenditure during the training sessions. Patients in the control group will perform light resistance training without any walking exercise.

• Behavioral: Walking Exercise
  Three times per week for 3 months
• Behavioral: Control--Resistance Training
  Three times per week for 3 months

• Experimental: 1
  Home-based program with progressive increases in exercise duration and intensity (i.e., cadence); walking duration will be longer for the home-based group because the intensity of walking will be lower than the graded treadmill walking performed by the supervised group
  Intervention: Behavioral: Walking Exercise
• Experimental: 2
  Supervised program consisting of graded treadmill walking, with progressive increments in exercise duration from 15 to 40 minutes, and progressive increments in exercise intensity from 50 to 70% of exercise capacity
  Intervention: Behavioral: Walking Exercise
• Active Comparator: 3
  Light resistance training without any walking exercise
  Intervention: Behavioral: Control--Resistance Training

• Gardner AW, Poehlman ET. Exercise rehabilitation programs for the treatment of claudication pain. A meta-analysis. JAMA. 1995 Sep 27;274(12):975-80.
• Gardner AW, Katzel LI, Sorkin JD, Bradham DD, Hochberg MC, Flinn WR, Goldberg AP. Exercise rehabilitation improves functional outcomes and peripheral circulation in patients with intermittent claudication: a randomized controlled trial. J Am Geriatr Soc. 2001 Jun;49(6):755-62.
• Gardner AW, Katzel LI, Sorkin JD, Goldberg AP. Effects of long-term exercise rehabilitation on claudication distances in patients with peripheral arterial disease: a randomized controlled trial. J Cardiopulm Rehabil. 2002 May-Jun;22(3):192-8.
• Gardner AW, Killewich LA, Montgomery PS, Katzel LI. Response to exercise rehabilitation in smoking and nonsmoking patients with intermittent claudication. J Vasc Surg. 2004 Mar;39(3):531-8.
• Gardner AW, Montgomery PS, Flinn WR, Katzel LI. The effect of exercise intensity on the response to exercise rehabilitation in patients with intermittent claudication. J Vasc Surg. 2005 Oct;42(4):702-9.
• Gardner AW, Parker DE, Montgomery PS, Scott KJ, Blevins SM. Efficacy of quantified home-based exercise and supervised exercise in patients with intermittent claudication: a randomized controlled trial. Circulation. 2011 Feb 8;123(5):491-8. Epub 2011 Jan 24.

Inclusion Criteria:

• Positive history of intermittent claudication assessed by the San Diego Claudication Questionnaire
• Exercise limited by intermittent claudication during a screening treadmill test using the Gardner protocol
• Ankle/brachial index (ABI) less than 0.90 at rest, which decreases to less than 0.73 immediately following the treadmill exercise test

Exclusion Criteria:

• Absence of PAD (peripheral artery disease)
• Asymptomatic PAD (Fontaine stage I)
• Rest pain due to PAD (Fontaine stage III)
• Tissue loss due to PAD (Fontaine stage IV)
• Medical conditions that are contraindicative for exercise according to the American College of Sports Medicine (e.g., acute myocardial infarction, unstable angina, etc.)
• Cognitive dysfunction (mini-mental state examination score less than 24)