Combined spiroergometry and31P-MRS of human calf muscle during high-intensity exercise.
Simultaneous measurements of pulmonary oxygen consumption (VO2), carbon dioxide exhalation (VCO2) and phosphorus magnetic resonance spectroscopy (31P-MRS) are valuable in physiological studies to evaluate muscle metabolism during specific loads. Therefore, the aim of this study was to adapt a commercially available spirometric device to enable measurements of VO2and VCO2whilst simultaneously performing31P-MRS at 3 T. Volunteers performed intense plantar flexion of their right calf muscle inside the MR scanner against a pneumatic MR-compatible pedal ergometer. The use of a non-magnetic pneumotachograph and extension of the sampling line from 3 m to 5 m to place the spirometric device outside the MR scanner room did not affect adversely the measurements of VO2and VCO2. Response and delay times increased, on average, by at most 0.05 s and 0.79 s, respectively. Overall, we were able to demonstrate a feasible ventilation response (VO2= 1.05 ± 0.31 L/min; VCO2= 1.11 ± 0.33 L/min) during the exercise of a single calf muscle, as well as a good correlation between local energy metabolism and muscular acidification (τPCr fastand pH; R2= 0.73, p < 0.005) and global respiration (τPCr fastand VO2; R2= 0.55, p = 0.01). This provides improved insights into aerobic and anaerobic energy supply during strong muscular performances.
Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany.
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http://orcid.org/0000-0001-9601-6792
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Moll
Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany.
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Gussew
Ganshorn Medizin Electronic GmbH, Niederlauer, Germany.
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Hein
Exercise Science, Institute of Sport and Movement Science, University of Stuttgart, Stuttgart, Germany.
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Stutzig
Medical Physics Group, Institute of Diagnostic and Interventional Radiology, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany.|Michael Stifel Center for Data-Driven and Simulation Science Jena, Friedrich Schiller University Jena, Jena, Germany.
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Reichenbach
D000328:Adult; D004734:Energy Metabolism / Q000502:physiology; D004867:Equipment Design; D019544:Equipment Failure Analysis; D016552:Ergometry / Q000295:instrumentation* / Q000379:methods; D006801:Humans; D007866:Leg / Q000033:anatomy & histology / Q000502:physiology; D009682:Magnetic Resonance Spectroscopy / Q000295:instrumentation* / Q000379:methods; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000502:physiology*; D010092:Oximetry / Q000295:instrumentation* / Q000379:methods; D010101:Oxygen Consumption / Q000502:physiology*; D010758:Phosphorus / Q000493:pharmacokinetics*; D010807:Physical Endurance / Q000502:physiology; D013147:Spirometry / Q000295:instrumentation* / Q000379:methods
D010758:Phosphorus
muscle metabolism; phosphorus magnetic resonance spectroscopy; pulmonary gas exchange; spiroergometry