Effect of training on plasma catecholamines in post myocardial infarction patients

Exercise induced plasma catecholamine levels, of post myocardial infarct patients, were compared before and after a 27 week training program in two groups, Heavy Intensity Exercise (H.I.E.) and Light Intensity Exercise (L.I.E.). The men (age 38-54 years) were exercised on a bicycle ergometer at constant submaximal work loads (test load) and to a symptom limited maximum work load, both before and after the training・ program. Forearm venous samples were obtained after 30 minutes rest and within 3 minutes of completion of the test load. After training a significant increase in both maximum work load and heart rate (PC0.05) was observed in the II.I.E. group. At the test loud these individuals had a small (6%) decrease in heart rate. No significant changes were observed in the L.I.E. group at submaxinuim or maximum exercise. Prior to training, exercise resulted in a significant increase in norepinephrine (NE) with no change in epinephrine (E). Training resulted in a significant reduction (P<0.05) in the NE response at the test load of the H.I.E. group while no change was found in the L.I.E. group. Endurance jogging reduced the sympathetic response to moderate exercise.