Strength Training in Walking Tolerance in Intermittent Claudication Patients
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
|Peripheral Arterial Disease Hypertension Diabetes||Behavioral: Walking Training Behavioral: Strength Training||Phase 3|
|Study Design:||Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Treatment
|Official Title:||Effects of Strength Training and Walking Training on Physical Fitness of Patients With Intermittent Claudication|
- Total Walking Distance [ Time Frame: 12 weeks ]The maximal walking distance
|Study Start Date:||July 2005|
|Study Completion Date:||December 2008|
|Primary Completion Date:||August 2008 (Final data collection date for primary outcome measure)|
Active Comparator: Strength training
Patients who performed strength training. The strength training program was composed by 8 exercises for whole body performed at sub-maximal intensity prescribed according to the patients self-perceived effort
Behavioral: Strength Training
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.
Active Comparator: Walking training
Patients who performed walking training. The walking training was performed in a treadmill using sub-maximal intensity prescribed based in patients self perceived effort
Behavioral: Walking Training
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.
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.
Please refer to this study by its ClinicalTrials.gov identifier: NCT00879697
|São Paulo, Brazil, 05588000|
|Study Chair:||Maria FN Marucci, PhD||University of Sao Paulo|