Strength Training in Walking Tolerance in Intermittent Claudication Patients
Condition: Peripheral Arterial Disease; Hypertension; Diabetes
MeSH terms: Peripheral Arterial Disease; Peripheral Vascular Diseases; Intermittent Claudication
Study type: Interventional
Phase: Phase 3

Summary: 
      Background: Muscle atrophy and reduced leg strength are related to exercise intolerance in
      patients with intermittent claudication (IC), suggesting that strength training (ST) could
      improve exercise performance in these patients.

      Objective: Analyze the effects of ST in walking capacity in patients with IC comparing with
      walking training (WT) effects.

      Intervention: Patients were randomized into ST and WT. Both groups trained twice a week, for
      12 weeks, at the same rate of perceived exertion. ST consisted of 3 sets of 10 repetitions of
      whole body exercises. WT consisted of 15 two-minute bouts of walking intercalated with 2
      minutes of resting.

      Measurements: Walking capacity, peak VO2, walking economy, ankle brachial index, ischemic
      window and knee extension strength
    

Detailed description: 
      From July 2005 to December 2006, three hundred patients with peripheral arterial disease, who
      were enrolled in a tertiary center specialized in vascular disease and were able to walk for
      at least 2 minutes at 2 miles per hour, were invited to a meeting at which explanations about
      this study were given. 80 patients attended the meeting, 60 of them decided to take part of
      the study, and 52 attended for the screening tests.

      Patients were included in the study if they met the following criteria: Fontaine stage II
      peripheral arterial disease, symptoms of IC for at least 6 months, ankle/brachial index (ABI)
      at rest ≤ 0.90 in 1 or 2 legs, reduction of ABI after treadmill test, and exercise tolerance
      limited by IC. Patients were excluded under the following conditions: presence of chronic
      lung disease, inability to obtain ABI measurement due to noncompressible vessels, exercise
      tolerance limited by factors other than claudication (eg, dyspnea or orthopedic problems),
      poorly controlled blood pressure, presence of electrocardiogram response suggestive of
      myocardial ischemia during the exercise test, and history of revascularization in the
      previous year.

      Procedures Patients were randomly (by drawing lots) divided into 2 groups: strength (ST, n =
      17) and walking (WT, n = 17) training. They were evaluated at baseline (pre-training) and
      after 12 weeks of exercise training (post-training). During evaluations were assessed
      exercise tolerance and strength.

      Both training programs (ST and WT) were supervised, conducted twice a week, lasted for 12
      weeks, and started after a 2-week preconditioning-orientation phase. In both programs, rate
      of perceived exertion during exercise was kept similar and between 11 to 13 on the15-grade
      Borg scale. Furthermore, the duration of exercise sessions was prescribed as 30 min of
      exercise for ST and WT groups.
    

Intervention name(s): Walking Training; Strength Training
Intervention type(s): Behavioral; Behavioral
Intervention description(s): The Walking Training program was performed using a treadmill. In each session, patients performed fifteen 2-min bouts of exercise followed by a 2-min rest interval, as previously described. Walking speed was set in order to induce perceived exertion of 11 to 13 and claudication pain in the last 30 seconds of each exercise bout.; The strength training program consisted of 8 exercises (leg press, crunches, unilateral knee extension, seated row, unilateral knee flexion, seated bench press, calf raises on leg press, and seated back extension). In each exercise, subjects performed 3 sets of 10 repetitions with a 2-min interval between sets and exercises.
Other intervention name(s): Walk training; Walk exercise; Resistance training; Weight training
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: peripheral arterial disease; exercise; resistance training; cardiac rehabilitation