Kinetics of pulmonary oxygen uptake and muscle phosphates during moderate-intensity calf exercise

• DOI: 10.1152/jappl.1996.81.3.1331
• Publication Date: 2017-12-22T07:43:09Z
• Authors: C. R. McCreary; P. D. Chilibeck; G. D. Marsh; D. H. Paterson; D. A. Cunningham; R. T. Thompson
• Keywords: Intensity; Exercise intensity

The purpose of this study is to directly compare the dynamic responses phosphocreatine (PCr) and P(i) those oxygen uptake (VO2) measured at lung during transitions from moderate-intensity exercise. Changes in PCr were by 31P-nuclear magnetic resonance spectroscopy, changes VO2 breath mass spectroscopy square-wave ankle plantar flexion exercise 11 subjects (7 men 4 women; mean age 27 yr). Three repeated averaged for improvement signal-to-noise ratio phosphate data, 12 measurements. Averaged fit with a monoexponential curve determination time constant (tau) responses. Mean tau values on transients PCr, P(i), phrase 2 47.0, 57.7, 44.5 s, respectively, whereas means off 44.8, 42.1, 33.4 respectively. There no significant differences between phosphate- VO2-measured or transients. similarity kinetics supports linear first-order respiratory control models. Measurement phase pulmonary small-muscle-mass reflect muscle (and consumption).