Supervised exercise protocol for lower limbs in subjects with chronic venous disease: an evaluator-blinded, randomized clinical trial

Background: Chronic venous insufficiency (CVI) causes pathophysiological changes in the lower-limb muscles, particularly the calf muscles, and limits ankle range of motion (ROM). These changes reduce functional activities and decrease quality of life (QOL). Although several studies have shown the benefits of exercise (strengthening the calf muscles to improve calf-muscle pumping and QOL) in patients with CVI, few studies are randomized controlled trials. This has led to a weak indication of exercise for the treatment of patients with CVI. The aim of this study is to analyze the effects of a supervised exercise program to improve calf-muscle endurance as well as QOL in patients with CVI.

Methods/design: This is an evaluator-blind, randomized clinical trial with an 8-week duration and a follow-up evaluation at week 16. A pilot study with subjects with a CVI diagnosis will be performed to calculate sample size. The participants will be randomly allocated (1:1) into a treatment or a control group (usual care/no intervention). The treatment intervention consists of a bi-weekly supervised exercise program of the lower limbs that will include aerobic training, strengthening and cardiovascular exercises. The participants from both groups will participate in a health education lecture. Primary outcomes are changes in calf-muscle endurance and QOL score. Secondary outcomes are changes in exercise capacity, ankle ROM, electrical muscle activity and cardiac output. The first statistical comparison will be performed after 8 weeks' intervention.

Discussion: Patients with CVI may have an impaired calf-muscle pump and decreased exercise capacity. A randomized controlled trial evaluating a supervised exercise program should provide much needed information on the management of CVI to promote health and independence.

Trial registration: This study was registered on the Brazilian Clinical Trials Database (REBEC) (RBR-57xtk7). The results will be disseminated at scientific events, presentations, and publications in peer-reviewed journals.