FIG. 1.

EKIT pulse sequence and ³¹P magnetization exchange pathways. a: The EKIT pulse sequence consists of a low-power, frequency-sweep inversion pulse, followed by a constant delay period, t_d, and a hard readout pulse. b: ³¹P magnetization exchange system in skeletal muscle, showing the various exchange pathways that are possible in skeletal muscle, including phosphorous chemical exchange reactions indicated by vertical arrows, and Nuclear Overhauser Effect (NOE) indicated by horizontal arrows. ATP and ADP are marked by rectangular boxes. A five-pool model including Pi, PCr and ATP but not ADP, was adopted in this work. Abbreviations: AK, adenylate kinase; CK, creatine kinase.