No abstract

PurposePrior research has shown that running squats on unstable surfaces may be useful in increasing antagonist muscle and body centre activity; nonetheless, the evidence for improved muscle strength-power is contradictory. In parallel, low-intensity strength training with partial blood flow restriction is effective in developing strength, hypertrophy, and muscular endurance. Combining both modalities could complement the benefits of exercising on unstable surface. Our objective was to compare the acute effects of 4 exercise types with or without partial blood flow restriction under stable and unstable conditions.MethodsSeven volunteers performed 4 protocols: exercises with high-intensity overload and stable conditions, low-intensity overload with blood flow restriction and stable conditions, unstable conditions without blood flow restriction, and unstable conditions with blood flow restriction. At the beginning, end, and recovery of each protocol, physiological variables were measured: heart rate, subjective perception of effort, blood lactate, and posturographic variables (total distance with eyes open and closed).ResultsExercises with stable surfaces generated greater physiological stress than both exercises on unstable surfaces. Furthermore, incorporating blood flow restriction into unstable exercise allowed an increase in the physiological demand without altering postural balance. There were only significant changes in postural balance in the high-intensity protocol with stable conditions.ConclusionsExercises combining partial blood flow restriction on stable and unstable surfaces increase the physiological demands without altering postural balance compared with high-intensity exercise on a stable surface.

BACKGROUND: Recent evidence has suggested that reversal of gray or white matter abnormalities could be a criterion of recovery in patients with chronic pain. OBJECTIVE: To determine the effectiveness of exercise-based interventions in reversing gray and white matter abnormalities in patients with chronic musculoskeletal pain. METHODS: An electronic search was performed in the MEDLINE (Via PubMed), EMBASE, Web of Science, LILACS, SPORTDiscus, CINAHL, PEDro, and CENTRAL databases for articles published up to November 2022. Randomized clinical trials (RCTs) including patients with chronic musculoskeletal pain, which assessed the change in gray and white matter abnormalities after exercise-based interventions were selected. The risk of bias was assessed using the Risk of Bias II tool. RESULTS: Four RCTs were included (n= 386). Three studies showed reversal of abnormalities with exercise-based interventions compared to control groups. The reversal was observed in the gray matter volume in the medial orbital prefrontal cortex and in the supplementary motor area of patients with osteoarthritis, in the hippocampus, insula, amygdala and thalamus in fibromyalgia patients. Furthermore, in patients with chronic spinal pain, reversal was observed in the gray matter thickness of the frontal middle caudal cortex and in the caudate, putamen and thalamus gray matter volume. CONCLUSIONS: There is insufficient evidence to determine the effectiveness of exercise-based interventions for reversing gray and white matter abnormalities in patients with chronic pain. Further studies are still needed in this field.