VASCULAR CONTROL OF NUTRIENT DELIVERY BY FLOW REDISTRIBUTION WITHIN MUSCLE - IMPLICATIONS FOR EXERCISE AND POSTEXERCISE MUSCLE METABOLISM

There is evidence for non-nutritive flow routes within, or associated with, skeletal muscle. Large capillary-like structures are possible ca ndidates. The proportion of flow distributed between nutritive and non -nutritive routes appears to be tightly regulated and can control musc le metabolism and contraction by regulating delivery and product remov al. The portion of flow that is carried by the non-nutritive routes at rest affords a flow reserve for amplifying nutrient delivery as muscl e begins to work and may determine post-exercise metabolism inappropri ate signals, however, may diminish nutritive flow to the detriment of muscle performance and post-exercise recovery. New technologies should allow the identification of the non-nutritive routes.