Time resolved observation of BOLD effect in muscle during isometric exercise

Introduction The BOLD-contrast mechanism arises from the change of blood oxygenation during cortical activation as a consequence of the increased arterial blood supply, which is most likely due to the increased oxygen demand. It has been originally suggested for the observation of neuronal activation (1). Recently it could be demonstrated, that changes in blood oxygen level can also be used for the observation of myocardial perfusion. In skeletal muscles an increase in perfusion as been observed by Frank using arterial spin label (ASL) techniques (2). The purpose of this study was to demonstrate, whether a BOLD-effect arises during muscle exercise and to assess its temporal signature.