title: Simultaneous surface electromyography (SEMG) and 31P-MR spectroscopy measurements of the lumbar back muscle during isometric exercise.
abstract: The aim of this study was to demonstrate the feasibility of simultaneous surface electromyography (SEMG) and 31P-MR spectroscopy (31P-MRS) measurements on the back muscle of volunteers during the performance of an isometric exercise. Six volunteers (three male, three female) performed a modified Biering-Sörensen test inside a 1.5 T MR scanner while simultaneously recording SEMG signals. A surface coil was used for 31P-MRS with a CSI sequence. Spectra were collected with a voxel resolution of 40 mm x 40 mm x 100 mm and a temporal resolution of 30 s during periods of rest, sustained muscle contraction and recovery. The duration of muscle contraction was 150 s. SEMG analysis yielded a decrease of the mean SEMG frequency of approximately 20%. The SEMG amplitudes were constant or increased up to approximately 150% during exercise. 31P-MRS showed a maximum decrease of the phosphocreatine (PCr) amplitude down to approximately 32% of its initial value. Simultaneously, a doubling of the inorganic phosphate (Pi) signal was observed. The present study demonstrates that simultaneous SEMG and 31P-MRS measurements of the back muscle are feasible during isometric exercises.
authors.affiliation: Institute of Diagnostic and Interventional Radiology, Friedrich-Schiller University Jena, Bachstr. 18, 07740 Jena, Germany. reinhard.rzanny@med.uni-jena.de
authors.forename: R
authors.initials: R
authors.lastname: Rzanny
authors.forename: R
authors.initials: R
authors.lastname: Grassme
authors.forename: J R
authors.initials: JR
authors.lastname: Reichenbach
authors.forename: M
authors.initials: M
authors.lastname: Rottenbach
authors.forename: A
authors.initials: A
authors.lastname: Petrovitch
authors.forename: W A
authors.initials: WA
authors.lastname: Kaiser
authors.forename: H C
authors.initials: HC
authors.lastname: Scholle
mesh_terms: D000328:Adult; D004576:Electromyography / Q000379:methods*; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008161:Lumbosacral Region / Q000502:physiology*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D010725:Phosphocreatine / Q000378:metabolism; D010758:Phosphorus / Q000378:metabolism
chemical_list: D010725:Phosphocreatine; D010758:Phosphorus