Metabolic Response of Forearm Muscle to Graded Exercise in Type II Diabetes Mellitus: Effect of Endurance Training

1996 ◽  
Vol 21 (2) ◽  
pp. 120-133 ◽  
Author(s):  
Deborah A. DeVries ◽  
Gregory D. Marsh ◽  
R. Terry Thompson ◽  
N. Wilson Rodger
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Endurance Training ◽  
Intracellular Ph ◽  
Muscle Metabolism ◽  
Incremental Exercise ◽  
Resonance Spectroscopy ◽  
Type Ii ◽  
And Control ◽  
Over Time

In this study, 31P nuclear magnetic resonance spectroscopy was used to monitor muscle metabolism in Type II diabetic subjects (n = 10) during an incremental exercise test. Also the exercise responses of diabetic subjects (n = 4) following submaximal endurance training were assessed and compared to healthy controls (n = 5). Responses to incremental exercise in the diabetic subjects were consistent over time despite minor fluctuations in metabolic control. In the diabetic and control groups, after 12 weeks of training the forearm flexor muscles, power output at the intracellular threshold of acidosis (IT) increased (p <.01) similarly: T0 versus T12: 0.90 ± 0.09 versus 1.20 ± 0.13 and 1.03 ± 0.07 versus 1.22 ± 0.10 W, respectively. Minimum intracellular pH reached at peak exercise was unchanged after training. The control group, however, became more acidic versus the diabetic group (p <.05) in response to progressive exercise. This difference was maintained over time. Endurance training elicited similar adaptations in forearm muscles of Type II diabetic and control subjects, although there were differences between the two groups in intracellular pH during exercise. Key words: magnetic resonance spectroscopy, muscle metabolism, exercise

Biochemical adaptations to training: implications for resisting muscle fatigue

1991 ◽  
Vol 69 (2) ◽  
pp. 274-278 ◽  
Author(s):  
Kevin K. McCully ◽  
B. J. Clark ◽  
Jane A. Kent ◽  
John Wilson ◽  
Britton Chance
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Muscle Fatigue ◽  
Endurance Training ◽  
Inorganic Phosphate ◽  
Muscle Metabolism ◽  
Resonance Spectroscopy ◽  
Effect Of Ph ◽  
Force Development ◽  
Generating Capacity

Skeletal muscle activity is invariably associated with a decline in force-generating capacity (fatigue). The build-up of metabolic by-products such as intracellular H+ and inorganic phosphate (Pi) has been shown to be one of the potential mechanisms of muscle fatigue. The use of phosphorus magnetic resonance spectroscopy is a repeatable and useful tool to study the effect of pH and Pi on force development. When maximal exercise is preceded by submaximal exercise to reduce the starting muscle pH and increase Pi; the degree of muscle fatigue correlates more strongly with [Formula: see text] than pH or R alone. However, other studies in humans have found that [Formula: see text] does not always correlate well with fatigue. The use of ramp exercise protocols allow repeatable and sensitive measurement of changes in muscle metabolism in response to endurance training. Chronic electrical stimulation in dogs and endurance training in humans results in reduced pH and Pi changes at the same exercise intensities. This means that the effect of pH and Pi in depressing force development is reduced, which could partially explain the increased fatigue resistance seen following endurance training.Key words: magnetic resonance spectroscopy (31P-MRS), muscle metabolism, exercise, inorganic phosphate, pH.

scholarly journals A phosphorus-31 nuclear magnetic resonance investigation of intracellular environment in human normal and sickle cell blood

Blood ◽  
1979 ◽  
Vol 54 (1) ◽  
pp. 196-209 ◽  
Author(s):  
YF Lam ◽  
AK Lin ◽  
C Ho
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Nuclear Magnetic Resonance Spectroscopy ◽  
Intracellular Ph ◽  
Sickle Cell ◽  
Resonance Spectroscopy ◽  
Blood Samples ◽  
Intracellular Environment ◽  
Nuclear Magnetic

Abstract Intracellular pH and 2,3-diphosphoglycerate concentration in sickle cell amenia and normal human blood samples were measured by means of phosphorus-31 nuclear magnetic resonance spectroscopy. To monitor the concentrations of various internal phosphorylated metabolites of intact red blood cells, heparinized blood samples were used and were incubated at 37 degrees C with 5.6% C92, 25% O2, and 69.4% N2. The 31P chemical shifts of phosphorylated compounds, such as 2,3-diphosphoglycerate, adenosine 5′-triphosp-ate, and inorganic phosphate, depend on pH, and by using an appropriate calibration curve, the intracellular pH of intact erythrocytes can be obtained. The intracellular pH values in fresh sickl cell blood and normal blood were found to be 7.14 and 7.29, respectively. However, the whole-blood pH, as measured by a standard pH meter, was found to be 7.54 for both types of blood. The initial concentration of 2,3-diphosphoglycerate in sickle cell blood was about 30% higher, but it was depleted much faster during incubation than that in normal blood. The difference in intracellular pH between these two types of blood samples remained constant during incubation, even after depletion of 2,3-diphosphoglycerate. These results suggest that there are differences in intracellular environment between normal and sickle cell blood. Thus, 31P nuclear magnetic resonance spectroscopy provides a fast, direct, continuous, and noninvasive way to monitor the intracellular environment of intact erythrocytes.

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