title: Muscle phosphorus magnetic resonance spectroscopy oxidative indices correlate with physical activity.
abstract: The purpose of this study was to assess the effect of physical deconditioning on skeletal muscle's oxidative metabolism as evaluated by phosphorus-31 magnetic resonance spectroscopy ((31)P MRS). Twenty-seven subjects without muscle disease, representing a wide range of fitness levels, were evaluated with (31)P MRS. Spectra were obtained at rest and during recovery from in-magnet exercise. The data show a significant correlation between maximum resting metabolic equivalent (MET) score and the following (31)P MRS recovery indices: adenosine diphosphate and phosphocreatine recovery half-time; initial phosphocreatine resynthesis rate; calculated estimation of mitochondrial capacity; pH at end of exercise; and phosphocreatine depletion. In addition, significant differences between the deconditioned and conditioned group were found for all of the aforementioned recovery indices. At rest, only the inorganic phosphate concentration was significantly different between the two groups. These data indicate that physical activity level should be taken into account when assessing patients' oxidative metabolism with (31)P MRS.
authors.affiliation: Magnetic Resonance Spectroscopy Unit, Montreal Neurological Institute & Hospital, 3801 University Street, Montreal, Quebec H3A 2B4, Canada.
authors.forename: M C
authors.initials: MC
authors.lastname: Tartaglia
authors.forename: J T
authors.initials: JT
authors.lastname: Chen
authors.forename: Z
authors.initials: Z
authors.lastname: Caramanos
authors.forename: T
authors.initials: T
authors.lastname: Taivassalo
authors.forename: D L
authors.initials: DL
authors.lastname: Arnold
authors.forename: Z
authors.initials: Z
authors.lastname: Argov
mesh_terms: D000244:Adenosine Diphosphate / Q000378:metabolism; D000328:Adult; D015444:Exercise / Q000502:physiology; D005260:Female; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D008931:Mitochondria, Muscle / Q000378:metabolism; D018482:Muscle, Skeletal / Q000378:metabolism / Q000502:physiology*; D010084:Oxidation-Reduction; D010710:Phosphates / Q000378:metabolism; D010725:Phosphocreatine / Q000096:biosynthesis / Q000378:metabolism; D010758:Phosphorus / Q000378:metabolism / Q000502:physiology*; D010761:Phosphorus Radioisotopes; D010809:Physical Fitness / Q000502:physiology*; D012146:Rest / Q000502:physiology
chemical_list: D010710:Phosphates; D010761:Phosphorus Radioisotopes; D010725:Phosphocreatine; D010758:Phosphorus; D000244:Adenosine Diphosphate