It is particularly effective in promoting blood vessel health. Beetroot juice increases brain blood flow, which enhances cognitive function and neuromuscular control. Sean Flanagan and co-workers from the Ohio-State University found that supplementing beetroot extract for three days improved neuromuscular function in before, during and after an intense weight-training workout, compared to a placebo (fake beetroot). Motor unit firing rates were lower at the onset of exercise, and continued as the muscular fatigued. This showed that the supplement promoted neuromuscular control during fatiguing exercise. Motor units are nerve-muscle combinations that control movements during sports.