Blood Flow Restriction Exercise for Those With SCI

Spinal cord injuries (SCI) are among the most debilitating conditions an individual can sustain with the estimates of SCI incidence in the United States at 12,000 new cases per year. The loss of innervation to the tissues muscle below the level of the lesion results in reduced physical activity which leads to an array of secondary complications including muscle atrophy, cardiovascular and metabolic disease, obesity and vascular dysfunction. This further leads to exercise intolerance, reduced quality of life and depression. Although current rehabilitative programs focus on improving muscle strength in this population, the efficacy of these programs is challenged by the injury related motor impairment, which limits the exercise intensity and subsequent positive muscular adaptations. Therefore, development of an exercise program that promotes maximal muscular adaptations to light intensity exercise could greatly improve the efficacy of rehabilitation in the SCI population and help restore functional capacity and quality of life for these individuals. Blood flow restriction (BFR) exercise has shown tremendous promise for improving muscle size and strength in a variety of healthy and clinical populations, however the benefits of BFR exercise for those with SCI has not been established. Thus, the purpose of this Merit proposal is to conduct a comprehensive study that explores the benefits and risks of BFR exercise in the incomplete SCI population. In general individuals with chronic incomplete SCI will be recruited to partake in two 8-week training periods (20 sessions) that involve traditional knee extension/flexion exercise or knee extension/flexion exercise with blood flow restriction. There will be a series of measurements before and after the 8-week intervention to look at changes in muscle and vascular function. Specific Aim 1 will determine how the 8-weeks of BFR exercise influenced muscle strength (Biodex isokinetic dynamometer), muscle cross sectional area and vo