PRINCIPAL INVESTIGATOR(S ): John A. Rummel, Charles F. Sawin, and Edward L. 



Michel 



EXPERIMENT TITLE/NUMBER : Exercise Response 



PROGRAM/MISSION : Apollo 7-11, 14-17 



CLASSIFICATION : Human 



DISCIPLINE(S) : Cardiovascular, Respiratory, Behavioral science 



OBJECTIVES : To evaluate the physiological response to exercise pre- and 

 postflight in order to assure the success of lunar surface extravehicular 

 activity (EVA). This was not measured in space due to the redirected Apollo 

 program after the Apollo fire. 



PROTOCOL : A bicycle ergometer and graded stress protocol were utilized with 

 heart rate determining stress levels. The protocol was comprised of exercise 

 levels at heart rates of 120 (6 min.), 140 (3 min.), and 1 60 (3 min.). The 

 tests were conducted three times within F-30 days, and at R+24 hours, and R+36 

 hours. The workload, heart rate, blood pressure, and respiratory gas exchange 

 were measured every minute. 



EQUIPMENT : Bicycle ergometer, graded stress equipment, EKG, respiratory gas 

 exchange system. 



RESULTS : Heart rate was increased in the immediate postflight test an average 

 of 16 beat/min., but was not significantly elevated at the second test. The 

 relationship between heart rate and oxygen consumption was significantly 

 altered at all heart rate levels postflight. The blood pressure decreased 

 postflight (both systolic and diastolic) at the same heart rate. There was a 

 decrease in cardiac output (stroke volume) at the rate of 160 beat/min. 



CONCLUSIONS : There was a decrease in stroke volume, which could have been 

 caused by changes in circulating blood volume and/or redistribution of blood 

 volume to lower extremities. There were no significant changes in mechanical 

 or respiratory efficiencies. The heart rate was significantly elevated for 

 the same oxygen consumption. This, in conjunction with the reduced stroke 

 volume, maintained the same cardiac output/oxygen consumption relationship. 



PUBLICATIONS : 64, 78, 82, 107, 456, 457, 458, 460 



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