Abstract
Applying magnetic resonance methods to measure the metabolic response in
exercise poses a technical challenge because the construction of the
ergometer must use non-magnetic components and assess work in the confined
space of a magnet bore. The present report details the fabrication of a
non-magnetic ergometer for use in a standard Siemens 3 Tesla (T)
spectrometer. Using the ergometer, researchers can measure the 31P NMR
signals during leg muscle exercise and exercise recovery. In particular,
the phosphocreatine (PCr) kinetics during exercise recovery reflects the
mitochondrial oxidative capacity, and the inorganic phosphate (Pi) signal
tracks the cellular pH. The ergometer allows for a personalized, and
variable load to be lifted leading to total work performed across study
participants being similar regardless of their leg strength. The ergometer
then enables a standardized magnetic resonance spectroscopy (MRS)
comparison of leg muscle bioenergetics between study participants.