chapter 33 

 PHYSICAL FITNESS TESTS 



R. E. Sonnenburg 



U.S. Navy Mine Defense Laboratory 

 Panama City, Florida 



INTRODUCTION 



The Sealab living quarters permitted unrestricted physical motion. Comfortable bunks 

 were provided for sleeping. Food was available in wide variety and ample quantity. Daily ac- 

 tivities consisted of donning rubberized suits, swimming, performing light to moderate under- 

 water tasks at various depths above and below 205 ft, and doffing the swimming gear. The wa- 

 ter temperature was 50° to 55 °F. and caused shivering and cold discomfort which was relieved 

 by a hot shower in the Sealab cabin. 



The Sealab crew was divided into three teams of 10 men each. Each team stayed in the 

 Sealab n undersea habitat for two weeks. Members of Teams 1 and 2 reported subjective sen- 

 sations of fatigue and lassitude which seemed to impair their work performance capacity. 

 Since the work tasks were neither standardized nor measured and the physiological responses 

 were not recorded, the extent of the fatigue problem could not be ascertained. Thus it was de- 

 cided to study the daily physical fitness changes of Team 3 during its duty period in Sealab. 



METHOD 



Physical fitness was monitored by a test in which the heartbeat rate and pulmonary venti- 

 latory rate was measured before and immediately after a barbell lifting exercise. Prior to the 

 test program, the individual stood erect while his nose to deck distance was measured. The 

 exercise procedure consisted of raising and lowering a special 37-lb barbell from the deck to 

 nose level and return at the rate of 30 cycles per minute for a period of one minute. The ca- 

 dence of the exercise was controlled by an observer who used a watch sweep second hand to 

 pace the rate of the exercise. The exercise was performed in a steady, rhythmic manner and 

 the observer coached him to go "faster" or "slower" as his rate of exercise declined below or 

 exceeded one cycle per two seconds. 



The exercise test was performed each evening, excepting one instance (ME), between 2000 

 and 2100 hours. This test time was placed at the end of daily work activities in order to detect 

 fatiguing effects of the tasks or the environment, if such occurred. 



Heartbeat rate was counted for 30 seconds while the subject stood quietly before the exer- 

 cise and again immediately after the exercise. The observer used a stethoscope placed over 

 the apex of the heart and a watch sweep-second hand to count the heartbeat rate. The 30- 

 second count was multiplied by 2 and the frequency per minute thus calculated was recorded. 



The pulmonary ventilation rate was counted and timed by a second observer who placed 

 the back of his hand about an inch below the subject's nostrils in order to detect the incidence 

 of respiratory flow. A 30-second count was multiplied by 2 to obtain the frequency per minute 

 of the ventilatory rate. The ventilatory rate was recorded before and immediately after the 

 exercise. 



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