Very low load and low volume exercise associated with partial vascular occlusion in the treatment of knee osteoarthritis: a randomized and double-blind clinical trial.
Osteoarthritis, blood flow restriction, kaatsu, knee pain.
INTRODUCTION: Osteoarthritis (OA) is the most common rheumatic disease in the world. Knee OA is one of the most frequent generating chronic pain, physical dysfunction and reduced quality of life. Among the possible treatments, low load resistance exercises (20-30% of 1-RM) with partial vascular occlusion (EPVO) of have presented results similar to the traditional high intensity exercise (HIE) without vascular occlusion (loads>60% of 1-RM) as long as the total volume of exercise (load x number of repetitions) is paired. It is unclear, however, whether very low load and low volume EPVO generates clinical improvements similar to HIE in patients with knee OA. AIMS: To verify if very low load and low volume EPVO presents the same effects of HIE on pain, functionality, quality of life and neuromuscular performance in patients with knee OA. An additional objective is to identify which of the two exercises induces lower levels of pain and perceived exertion during exercise and greater adherence and satisfaction with the treatment. METHODS: This study will be a randomized, two-arm clinical trial, registered prospectively and and with masking of patients and evaluators. Two weekly sessions of treatment will be provided for 12 weeks (totaling 24 sessions). Patients will perform a standardized exercise protocol involving muscle strengthening of the thigh muscles with very low (10% of 1-RM) and low volume EPVO or EAIT (60% of 1-RM). Clinical outcomes will be collected by a masked assessor in relation to the allocation groups. The primary outcome will be the perception of knee pain assessed before, and after 12 weeks of treatment. . Secondary outcomes will be the perception of knee pain 1 month after the end of treatment, functionality, quality of life, neuromuscular performance, perceived knee pain and exertion during exercise and adherence and treatment satisfaction. Expected results: EPVO may reduce pain and improve function, quality of life, and neuromuscular performance in patients with knee OA in a manner similar to HIE. In addition, it is expected that patients who perform EPVO will experience lower pain and perceived exertion during exercise. If confirmed, these findings may point to very low load and low volume EPVO as an interesting alternative in the treatment of patients with knee OA, especially those unable to perform the exercises with high loads due to knee pain.