16. Respiration Tests

Subjects will be numbered from 1 to 12. Nine subjects will be examined daily according to a schedule to be made later. These tests will be made before breakfast every day except on the Sundays when the squad is in Boston. The time for these tests will be set so as not to interfere with the regular class work of the students.

In accordance with this agreement no food other than that served at table could be eaten. The men were particularly cautioned against the consumption of candies, peanuts, ices, etc., to which they were more or less accustomed. The following measurements were made for the most part with Squad A and also with Squad B during diet restriction:

Urine And Feces

Twenty-four hour amounts of urine were collected and the specific gravity and total nitrogen determined. To note the possibility of digestive disturbance, feces were collected at various intervals throughout the test. The nitrogen and total energy of the feces were determined, these supplying a measure of the digestibility of protein and total calories.

Body-Weight

As the foremost index of body condition and state of nutrition, body-weights were recorded under standard conditions, that is, with the subject nude, in the post-absorptive state, with an empty bladder, and without the previous drinking of water. Each weight was checked, not only by a member of the squad, but by a representative of the Nutrition Laboratory, and the date and time recorded.

Body-Surface Measurements

To serve the dual purpose of giving a record of the changes in body-surface and a general index of the physical state, a series of body-surface measurements was made according to the method of Du Bois. These measurements were supplemented by anatomical photographs taken at frequent intervals throughout the test.

Records Of Activity

No one factor plays a greater r61e in the consumption of energy than muscular activity. As the simplest index, crude though it may be, the pedometer was used. Furthermore, the men were frequently questioned as to their extraneous physical activities other than normal. During certain periods a schedule of the actual activities during a period of one week was obtained.

Pulse Measurements

The pulse is the best general index of the metabolic level; hence every effort was made to secure pulse measurements as frequently as possible, but under controlled and comparable conditions. These included observations with the subject lying quietly in the post-absorptive condition, sitting during meals, standing and in the post-absorptive condition, lying quietly before and after riding on a bicycle ergometer, standing before and after walking experiments, and during walking. Wrist counts were supplemented by standard electrocardiograms and electrocardiograms during exertion.

Clinical Examinations

Clinical examinations of Squad A and of Squad B during diet restriction were carefully made by Dr. Goodall. These included examinations of the heart, lungs, reflexes, glands, and blood pressure.

Blood Examination

Somewhat late in the test arrangements were made, through the kindness of Dr. George R. Minot of Boston, for a series of careful blood examinations. We were so fortunate as to secure the cooperation of Miss Anna L. Gibson and her associate, Miss M. B. Conover, who made the blood examinations on nearly every visit of the squads to Boston after December 19.

Body Temperature

Each morning prior to the gaseous metabolism experiments in Springfield, the temperature was taken in the mouth with a clinical thermometer, simply to show the absence of fever. For true physiological measurements we relied upon the temperature taken in the rectum at the end of the night experiments in the large chamber in Boston. To give a possible suggestion as to changes in skin temperature, electrical measurements of surface temperature were taken during the latter part of the test.

Gaseous Metabolism

The gaseous metabolism was measured under four different conditions: (1) With the subjects lying quietly and in the post-absorptive condition, by means of the respiratory-valve apparatus and the portable respiration apparatus; (2) with the subjects lying asleep after a light supper, in a night experiment with the group respiration chamber; (3) with the subjects in the post-absorptive condition and in the standing position; and (4) with the subject walking on the treadmill in the treadmill chamber. The first two measurements gave an indication of the basal metabolism of the subjects, the third provided a base line for the metabolism during walking, and the fourth supplied evidence of the energy requirements for the ordinary activities of the day. The fourth series of observations also gave information as to the effect of a reduced diet upon the efficiency of the men in ordinary physical activity.

Psycho-Physiological Measurements

An extended series of psychophysiological measurements was made by approved methods in both group and individual tests whenever the subjects visited Boston. Full details are given of the various tests in later sections.

Week-End Program

To illustrate the personal demands made upon the subjects as a result of these observations, a typical week-end program for Squad A is given. Beginning early Friday morning at Springfield, the activities of the squad are shown until the conclusion of the tests on Sunday in Boston.

Friday

5h30m a. m. Nine men ready for respiration experiments; 7 men portable respiration apparatus; 2 men respiratory-valve apparatus. Routine of experiments: Bladder emptied; weighed (stripped); lay on couch for preliminary period; mouth temperature taken; two periods (10 to 15 minutes each) on respiration apparatus; pulse and respiration rates taken during experiment; alveolar air determinations made for 2 men on respiratory-valve apparatus.

6h45m a. m. Breakfast; pedometer readings recorded.

9h30m to llh30m a. m. Bicycle ergometer experiments with Professor Johnson; 5-minute periods; subjects, Bro, Gul, Gar.

12h10m p. m. Dinner; pulse-rate counted at wrist by subject (sitting).

1h30m to 4h30m p. m. Bicycle ergometer experiments with Professor Johnson; subjects, Pec, Vea, Can, Moy, Spe, Mon, Tom, Kon, Pea.

6 p. m. Supper; pulse-rate counted at wrist by subject (sitting).

Saturday

5h30m a. m. Nine men ready for respiration experiments; regular routine followed. 7h30m a. m. Breakfast. 9h10m a. m. Train Springfield to Boston. llh36m a. m. Squad arrived in Boston. 12 (noon). Standard dinner at restaurant.

5 p. m. Standard supper at restaurant.

5h45m p. m. Squad arrived at Nutrition Laboratory.

6 to 7 p. m. Group psychological tests in library at Laboratory. For order of tests see section on technique (page 139) and program of research (page 149). Pulse-rates (sitting) during psychological tests; skin temperature measurements at end of psychological tests.

7 to 10h30m p. m. Individual psychological measurements in psychological laboratory (60 to 70 minute period); measurements given to 4 men simultaneously. When not occupied with psychological tests, the men were given the following: Clinical examination by Dr. Goodall; blood tests by Miss Gibson; Du Bois body-surface measurements; profile photographs; 5-minute practice in walking on treadmill. 10h00m to 10h30m p. m. Men went to bed in the group respiration chamber as soon as all had finished the tests previously mentioned. 10h45m p. m. Men all in bed, cover of group chamber closed; preliminary period of experiment began. . . 1lh15m p. m. Respiration experiment proper began; periods approximately 30 minutes long throughout the night.

Sunday

5 a. m. Respiration experiment ended. 5h50m a. m. Cover taken off group chamber.

6 a. m. Routine for each subject as follows: Rectal temperature and pulse-rate determined by observer with subject lying; subject then rose, emptied bladder, was weighed nude, dressed, and received standard laboratory breakfast. 6h30m to 9 a. m. Individual psychological measurements given to subjects, three men at a time, in 25-minute periods. Men then free for the rest of the day. On Jan. 6 and 28 for Squad B and Feb. 3 for Squad A, the program for Sunday morning was changed to include experiments on the treadmill and portable respiration apparatus. On these dates the Sunday morning program was as follows: 3h50m a. m. Respiration experiment in group chamber ended. 4 a. m. Cover taken off group chamber.

4h15m a. m. Rectal temperature and pulse-rate measured as before, also bladder emptied; first man weighed nude on second floor of Laboratory; he then dressed, was given a glass of water to drink, and went to third floor of Laboratory for experiments. Same routine followed for other men in turn. 4h25m a. m. to 1 p. m. Standing experiments with portable respiration apparatus, and walking experiments with treadmill apparatus; men called in turn at intervals of 20 to 30 minutes. Routine of experiment with portable respiration apparatus: Two experimental periods, each 12 to 15 minutes long; pulse and respiration rates taken during experiment; blood pressure taken at end of experiment.

Routine Of Treadmill Experiment

1 Electrodes adjusted and pulse-rate taken in hall outside of treadmill room; pulse-rate, sitting in treadmill room; pulse-rate, standing on treadmill; pulse-rate, transition standing to walking. Preliminary period: 4 minutes walking on treadmill, with cover off of chamber 2 1/2 minutes. Main period: Walking on treadmill, with cover on chamber, 20 minutes; electrocardiograms taken and approximate measurement of respiration rate made during 6th, 12th, and 24th minutes of walking. Visual counts of deflections of galvanometer each minute made during preliminary period and main period of experiment; total distance traveled recorded; total number of steps recorded. After experiment: Pulse-rate taken, transition walking to standing; successive blood-pressure measurements immediately at end of walking for period of 2 minutes; subject weighed with electrodes and dressed as on mill; blood pressure and radial pulse, sitting, for 10 minutes; strength of grip, but no other psychological measurements. Men dismissed as each finished the last test.