Dissociation of changes in metabolic rate and blood pressure with erythrocyte Na-K pump activity in older men after endurance training.
We examined whether changes in resting metabolic rate (RMR) and blood pressure in older normotensive men in response to endurance training were associated with alterations in the Na-K pump activity of plasma-bathed erythrocytes. Eleven men performed cycling exercise three times a week for 8 weeks, and six other men served as controls. Measurements included: RMR by indirect calorimetry, supine blood pressure, body composition by underwater weighing, plasma and erythrocyte Na and K parameters using flame photometry and ouabain. Peak VO2 increased 12% (p < .001), RMR increased 10% (p < .01), mean blood pressure decreased 5% (p < .05), erythrocyte K increased 5% (p < .01), plasma K decreased 7% (p < .001), and plasma Na decreased by 4% (p < .001) in response to training. Erythrocyte Na and Na-K pump rate did not change, nor did the individual changes correlate with changes in RMR or mean blood pressure. Exercise training increases RMR and reduces blood pressure in older men, but these changes are dissociated with erythrocyte Na-K pump activity.
Webb
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GD
College of Medicine, University of Vermont.
Poehlman
E T
ET
Tonino
R P
RP
D000255:Adenosine Triphosphate / Q000378:metabolism; D000273:Adipose Tissue; D000368:Aged; D001481:Basal Metabolism / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology*; D001823:Body Composition; D015992:Body Mass Index; D002149:Energy Intake; D004912:Erythrocytes / Q000378:metabolism*; D015444:Exercise / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption / Q000502:physiology; D010806:Physical Education and Training; D010807:Physical Endurance / Q000502:physiology*; D011188:Potassium / Q000097:blood; D012964:Sodium / Q000097:blood; D000254:Sodium-Potassium-Exchanging ATPase / Q000502:physiology*
D000255:Adenosine Triphosphate; D012964:Sodium; D000254:Sodium-Potassium-Exchanging ATPase; D011188:Potassium