TECHNICAL REPORT STANDARD TITLE PAGE 

1. Report No. 2. Government Accession No. 3. Recipient's Catalog No. 

FAA-AM-71-8 

4. Title and Subtitle 5. Report Date 

BIODYNAMIC EVALUATION OF AIR TRAFFIC CONTROL March 1971 

STUDENTS BETWEEN 1960-1963 6. Performing Organization Code 

7. Author(s) 8. Performing Organization Report No. 

Michael T. Lategola, Ph.D. 

9. Performing Organization Name and Address 10. Work Unit No. 

FAA Civil Aeromedical Institute 

P. o. Box 25082 11. Contract or Grant No. 

Oklahoma City, Oklahoma 73125 

13. Type of Report and Period Covered 

12. Sponsoring Agency Name and Address 

Office of Aviation Medicine 

Federal Aviation Administration OAM Report 

800 Independence Avenue, s.w. 14. Sponsoring Agency Code 

Washington, D.C. 20590 

15. Supplementary Notes 

16. Abstract 

Between 1960-1963, a large number of ATC students in training at the FAA 

Aeronautical Center in Oklahoma City underwent a broad spectrum of biomedical 

evaluations conducted by the Civil Aeromedical Research Institute (CARl). 

Approximately 1,270 of these students were evaluated for physical fitness. 

Included in this evaluation were measurements of height, weight, pulmonary vital 

capacity, maximum breathing capacity and maximum aerobic working capacity. 

Principal findings were: 1) physical fitness levels comparable to general population norms of health and 2) expected parameter decrements with age. The 

age-related decrements in the measured physical parameters generally paralleled 

the ATC training failure rate. These data will serve as baselines for future 

evaluations of career ATC personnel in relation to job performance and preventive 

maintenance of optimum cardiovascular health. 

17. Key Wards Air Traffic Control Students, 18, Distribution Statement 

Baseline Biodynamic Evaluation, Maximum ·Availability is unlimited. Document may 

Aerobic Work Capacity, Pulmonary Functior, be released to the National Technical 

Blood Pressure, Height, Weight, Age, Service, Springfield, Virginia 22151, 

Cardiovascular Health for sale to the public. 

19. Security Classif. (of this report) 20. Security Classif. (of this page) 21. No, of Pages 22. Price 

Unclassified Unclassified 10 $3.00 

=orm DOT F 1700.7 IB·69l 
ACKNOWLEDGMENTS 

The data in this report were collected by the staff of the former Biodynamics Branch of the CARl as well 'as some additional personnel from 

adjunct branches during the 1960-1963 time period. The contributions of 

Dr. Bruno Balke, his staff and all of the adjunct personnel participating in 

this endeavor during that time are herewith acknowledged. 
BIODYNAMIC EVALUATION OF AIR TRAFFIC CONTROL STUDENTS 

BETWEEN 1960-1963 

I. Introduction. 

Between 1960-1963, a large number of air 

traffic control (ATC) students being taught at 

the FAA Aeronautical Center in Oklahoma City 

underwent a broad spectrum of biomedical evaluations conducted by the Civil Aeromedical Research Institute (CARl). Since the total 

spectrum o£ ATC tasks demands various degrees 

o£ both mental and physical fitness in relation to 

acceptable minimum levels o£ job performance, it 

was felt that such initial biomedical measurements could be utilized longitudinally as baselines for subsequent job-related evaluations. 

This report will confine itself to the biodynamic 

baseline data gathered at that time. 

Approximately 1,270 of the students were 

evaluated £or physical fitness. Adjunct measurements of height, weight, and pulmonary 

£unction were also obtained. Because of the nonoptional necessity of evaluating up to 60 students 

per allotted day of testing, because of the limited 

number of staff on board and because the testing 

was carried out under essentially "field" conditions at temporary research facilities, an identical 

battery of parametric measurements was not obtained from each of the 1,331 students eventually 

processed. 'Vithin this context, priority was 

given to the measurement of maximum aerobic 

work capacity. 

II. Methods. 

The general protocol included measurements of 

unclo~hed height and weight, pulmonary vital 

capacity (VC) and maximum breathing capacity 

(MJ}C) and maximum aerobic work capacity 

(M:V02). The height and weight were measured 

to the nearest quarter inch and quarter pound 

respectively. 

The measurements of VC and MBC were obtained using a 13.5 liter "Collins" spirometer and 

standard spirometry techniques.1 The measured 

1 

volumes in both tests were converted to standard 

conditions of body temperature and pressure 

saturated (BTPS) and expressed in liters and 

liters per minute respectively. • The MV02 was measured using several 

equivalent methods. The most universally accepted method for obtaining this measurement is 

the standard treadmill test of Balke et aU Because of mandatory stringent scheduling o£ ATC 

courses, only one day per ATC class per two-week 

period was allowed for the MV02 evaluations. 

Since this necessitated the evaluation o£ up to 60 

~TC st.udents on any given testing day, and 

smce tins number could not be processed in one 

day using the standard treadmill test, other 

equivalent tests of shorter duration were developed and used for this purpose. The three adjunct tests most frequently used £or this purpose 

were a fifteen-minute running test,3 a £our-grade 

step test 4 and a £our-grade abbreviated treadmill test. 4 The running test was used preferentially for 1,183 of the 1,270 MV02 evaluations 

because several students could be processed 

simultaneously in one fifteen-minute period. The 

~f\~'02 values obtained from all four testing 

methods were ~xpressed as milliliters o£ oxygen 

tq~take per mmute per kilog~am body weight 

(V02/kg bw). The measured V02 was converted 

to standard conditions o£ temperature and pressure dry (STPD). 

As opportunity permitted, indirect blood 

pressure determinations were obtained on some 

of the students under seated, restinO" conditions • b 

just prior to MV02 testing. The data are based 

on averages of at least two successive determinations. These were obtained using standard equipment and technique. 5 

III. Results. 

Table I presents the frequency distributions of 

age, height and weight. The average age of the 
1,331 students who underwent partial or total 

testing was 27.7 years. Of the 1,331, approximately 40% were less than 25 years old and approximately 75% were less than 30 years old. 

The height and weight were obtained on 965 of 

the students. The average height and weight of 

this number were 69.7 inches and 162.1 pounds 

respectively. Figures 1-3 are graphic representations of the data in Table I. 

TABLE I. Frequency distributions of age, height and weight of ATC students in the 1960-1963 time period. Age is 

expressed as the nearest completed year, height to the nearest quarter inch and weight to the nearest quarter 

pound. 

Cumulative Height and Weight 

Age Bracket Average No. of %of %of 

Age Subjects Total No. Total No. Avg. Ht. Avg. Wt. No. of 

20-24 22.9 561 42.1 

25-29 26.7 410 30.8 

30-34 31.3 142 10.7 

35-39 37.5 109 8.2 

40-44 41.3 98 7.4 

45-49 45.8 8 0.6 

50-54 51.0 2 0.15 

55 59 55.0 1 0.05 

ALL 27.7 1331 100.00 

Table II presents the distributions of VC and 

MBC versus age. Both the absolute values and 

the actual/predicted x 100 ( act./pred. x 100) 

values of VC and MBC are tabulated. The 

predicted values of these two parameters were 

obtained from the nomograms of Baldwin et aU 

The numbers of subjects represented by the act./ 

pre<l. x 100 values of VC and MBC are much less 

than their respective absolute counterparts. 

This occurred because the predicted value nomo-

(inches) (pounds) Subjects 

42.1 69.5 158.2 411 

72.9 70.0 163.7 289 

.83. 6 69.5 163.9 108 

91.8 69.4 165.0 82 

99.2 70.1 172.5 70 

99.8 68.6 161.5 4 

99.95 68.5 149.6 1 

100.00 

100.00 69.7 162.1 965 

grams are based on age, height and weight and 

the latter two measurements were not obtained on 

all of the subjects who underwent VC and MBC 

testing. The absolute values of these two 

parameters manifested the expected trend of decrease with age. The act./pred. x 100 values 

iJ!.dicated that the mechanical aspects of pulmonary ventilation were grossly normal in this 

aliquot of subjects. Figures 4-7 present graphic 

representations of the data in Table II. 

TABLE II. Frequency distributions of vital capacity (VC) and maximum breathing capacity (MBC) versus age. 

Act./Pred. X values of both VC and MRC were calculated according to Baldwin, et al.1 

VITAL CAP A CITY 

Age Bracket Average No. of Act. 

v.c. Subj. --X 100 

L(BTPS) Pre d. 

20-24 4.8 498 107.5 

25-29 4.7 335 108.5 

30-34 4.6 120 107.9 

35-39 4.5 99 106.2 

40-44 4.3 87 104.5 

45-49 4.4 7 108.2 

50-54 3.8 2 105.3 

55-59 3.0 1 

ALL 4.7 1149 107.5 

Table III presents the distributions of resting 

systolic and diastolic blood pressures versus age. 

The average systolic and diastolic pressures for 

this relatively small sample of ;?tudents appear to 

lie within grossly normal ranges. The average 

2 

MAXIMUM BREATHING CAPACITY 

No. of Average No. of Act. No. of 

Subj. M.B.C. Subj. --X100 Subj. 

L/Min. (BTPS) Pre d. 

385 158.2 338 114.2 305 

248 154.7 218 115.9 189 

96 152.3 87 113.9 79 

75 149.6 79 116.6 67 

66 149.4 56 117.8 50 

3 146.3 2 126.7 2 

1 133.2 2 116.1 1 

131.8 1 

874 155.0 783 115.3 693 

diastolic pressure manifested an expected directional trend of increase with age. No consistent 

directional trend with •age appears obvious for the 

average systolic pressure. These data are 

graphically presented in Figure 8. 
TABLE III. Frequency distributions of average systolic and diastolic blood pressures versus age. 

Age Bracket 

Average Systolic 

(mm Hg) 

20-24 125.1 

25-29 123.8 

30-34 122.3 

35-39 125.4 

40-44 128.4 

45-49 122.0 

ALL 124.6 

Table IV presents the distribution of MVO., 

(in terms of maximum V02 /kg bw) versus age~ 

The trend of decreasing Mv'02 with age is 

apparent and conforms to general expectation. 

Of the 1,270 students tested, 92.2% were of 

Blood Pressure 

Average Diastolic No. of Subjects 

(mm Hg) 

79.8 95 

81.7 79 

82.7 24 

83.6 11 

86.2 16 

80.0 2 

81.4 227 

average fitness according to the Balke rating 

scale. 2 This rating scale is shown in Table V. 

The data in Table IV are presented graphically 

in Figure 9. 

TABLE IV. F'requency distribution of average maximum aerobic work capacity (MVO,) (in terms of maximum 

VO,Jkg bw) versus age. 

Average %of Cumulative "Balke" 

Age Bracket Maximum No. of Total %of Fitness 

V02/kg bw Subjects Number Total Rating 

(ml/min/kg) Number 

20-24 38.6 540 42.5 42.5 Average 

25-29 37.6 395 31.1 73.6 Average 

30-34 36.5 134 10.6 84.2 Average 

35-39 35.9 102 8.0 92.2 Average 

40-44 34.6 90 7.1 99.3 Poor 

45-49 32.9 6 0.46 99.76 Poor 

50-54 34.6 2 0.16 99.92 Poor 

55-59 29.7 1 0.08 100.00 Very Poor 

ALL 37.5 1270 100.00 100.00 Average 

TABLE V. Balke physical fitness rating scale. M:ets = multiples of the resting VO,Jkg lnv. Maximum treadmill grade 

was ascertained using the standard Balke treadmill test' in which treadmill velocity is held constant at 3.4 miles 

per hour and the slope of the treadmill is increased 1% per minute. 

Maximum Balke 

V02/kg bw Fitness 

(ml/min/kg) Rating 

<25 Pathological 

25-30 Very Poor 

30-35 Poor 

35-40 Fair or Average 

40-45 Good 

45-50 Very Good 

50-55 Excellent 

55+ Superior 

IV. Discusssion and Summary. 

The average height of 69.7 inches as measured 

on 965 ATC students in the 20-55 year age span 

is slightly greater than the United States populaMaximum Maximum 

Mets Treadmill Distance Run 

3 

Grade(%) in 15 Min. 

<7 <8 <0.75 

7-8 8-11 1.0 

9 11-14 1. 25 

10-11 14-17 1.5 

12 17-20 1. 75 

13-14 20-23 2.0 

15 23-26 2.25 

16+ 26+ 2.5+ 

tion norms 6 of 69.1 inches for the 25-34 year 

range, 68.5 inches for the 35-44 year range and 

68.2 inches for the 45-54 year range. The 

average weight of 162.1 pounds of this ATC 
population segment is somewhat less than the 

reported general population norms 6 of 169 

pounds for the 25-34 year range and 170 for the 

35-54 year range. These latter two norm weights 

have been corrected :for two pounds of clothing 

weight.6 The fact that this ATC group was 

taller and less heavy than general population 

norms is probably related to previous military 

screening since approximately 80% of the ATC 

students had recent military service. 

The VC and MBC of the students generally 

exceeded general population norms1 matched for 

age and body size. Whether purposively or 

otherwise, general pulmonary health screening 

was accomplished effectively. The average resting systolic and diastolic blood pressures of the 

sampled ATC segment lay within the agematched normal range of the general population. • The average MV02 of these students compared favorably with those of large United States 

general population as well as military population samples.2 The decrease of MV02 with age 

is not unexpected, but would not appear to be 

desirable since age-matched norms for many 

other countries exceed those of the United States 

by significant magnitudes/ 

During the 1960-1963 period, the Psychology 

Branch of the CARl performed concomitant 

aptitude studies on most of the same ATC 

students covered herein. One of their reports 8 

revealed that the satisfactory completion of ATC 

training was inversely related to age. From a 

total of 1,210 students represented in their 

analysis,8 satisfactory training completion was 

achieved by 55% o£ the students in the 21-26 

year range, 37% in the 27-32 year range, 26% 

in the 33-38 year range, 12% in the 39-44 year 

4 

range and none beyond 45 years of age. This 

general trend has been corroborated by data from 

successive ATC student classes up to and including those of the present day. This finding is 

consistent with the general observation of reduction in psychomotor performance capability 

with age. It is possible, therefore, that the agerelated changes in physical parameters, such as 

reported here, may reflect the concomitant agerelated psychomotor changes and/or may be part 

of a physical basis for the performance decrease 

per se. This possibility may be a moot point. 

Besides the moot possibility of a beneficial effect on psychomotor performance, the attainment 

and maintenance o£ an optimum state of general 

physical health has a second rationale which is 

far less moot. Such maintenance is generally 

accepted as a major deterrent against longitudinal incapacitative chronic diseases. The most 

serious category of these diseases is that of the 

cardiovascular system. Because of the high 

incidence, incapacitation and mortality rates associated with cardiovascular disease,9 any appreciable deterrence of this disease category in 

the ATC population should be beneficial to their 

longitudinal optimum job performance. 

The biodynamic data compiled in this report 

will serve as baselines for the subsequent assessment of longitudinal changes associated with 

chronological aging and health related aspects of 

job performance. It is hoped that these data 

may also be of use in the eventual delineation of 

improved norms £or an optimum state o£ 

cardiovascular health and in the detection of the 

earliest reversible departures £rom that optimum 

state. 
REFERENCES 

1. Baldwin, E. De F., A. Cournand and D. W. Richards, 

Jr. Pulmonary Insufficiency, Physiologic Classification, Clinical Methods of Analysis, Standard Values 

in Normal Subjects. MED., 27: 243, 1948. 

2. Balke, B. and R. W. Ware. An Experimental Study 

of "Physical Fitness" of Air Force Personnel. U.S. 

Armed Forces Med. Jour. 10: 657, 1959. 

3. Balke, B. A Simple Field Test for the Assessment of 

Physical Fitness. CARI Report No. 63-6, April, 1963. 

4. Nagle, F. and B. Balke. A Gradational Step Test for 

Assessing Cardiorespiratory Capacity : An Experimental Evaluation of Treadmill and Step Test Procedures. CARI Report No. 64-3, January, 1964. 

5. Bordley, J., C. A. R. Connor, W. F. Hamilton, W. J. 

Kerr and C. J. Wiggers. Recommendations for Blood 

5 

Pressure Determinations by Sphygmomanometers. 

CIRC., 4: 503, 1951. 

6. Stoudt, H. W., A. Damon and R. McFarland. Weight, 

Height and Selected Body Dimensions of Adults, 

United States-1960-1962. National Center for 

Health Statistics, Series II, No. 8, June, 1965. 

7. Physical Activity and Cardiovascular Health-International Symposium. JOUR. CANAD. MED. ASSOC. 

96 : 695-920, 1967. 

8. Trites, D. K. and B. B. Cobb. CARl Research on Air 

Traffic Control Specialists: Age, Aptitude and Experience as Predictors of Performance. CARI Unnumbered Report, January, 1964. 

9. Statistical Abstracts of the United States, 87th 

Edition, 1966. 
60 

40 

AVERAGE 

AGE (yrs.) 

20 

I 

I 

I 

0 

0./'.// 

I 

I 

I 

I 

I 

I 

o"" / 

/ 

// 

/// 

0/ 

o----o----o----o 

20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 

AGE BRACKET (yrs.) 

100 

75 

CUMULATIVE 

% OF TOTAL 

NUMBER 

50 

25 

FIGURE 1. Each bar height represents the ave:rage age (to the nearest completed year) of the individuals represented 

by the specified age bracket. The figure within each bar represents the number of individuals in that age bracket. 

These data represent a total of 1331 individuals. The open circles connected by dashed lines represent the cumulative % of the total number of individuals at each successive age bracket. 

70 

AVERAGE 

HEIGHT 

(inches) 

65 

20-24 25-29 30-34 35-39 40-44 45-49 

AGE BRACKET (yrs.) 

50-54 

FIGURE 2. Each bar height represents the average height (in inches) of the individuals within the specified age 

bracket. The figure within each bar is the number of individuals represented by that bar. These data represent a total of 965 individuals. 

6 


% 

120 

MAXIMUM 

BREATHING 

CAPACITY 

( Act. X 100) 

Pred. 

100 

20-24 25-29 30-34 35-39 40-44 45-49 

AGE BRACKET (yrs.) 

50-54 

FIGURE 7. Each bar height represents the average Act./Pred. X 100 maximum breathing capacity value of the individuals within the specified age bracket. The figure within each bar is the number of individuals represented by that bar. These data represent a total of 693 individuals. 

BL000120 

PRESSURE 

(mm Hg) 

100 

20-24 25-29 30-34 35-39 40-44 45-49 

AGE BRACKET (yrs.) 

FIGURE 8. Each bar height represents the average systolic (S) and diastolic (D) blood pressure values (in mm 

Hg) of the individuals witllin the specified age bracket. The figure within each pair of bars is the number of 

individuals represented by that bar pair. These data represent a total of 227 individuals. 

9 
40 

AVERAGE 

MAXIMUM 

V02 /Kg bw 

(ml/min/kg) 

35 

30 

/ 

20-24 25-29 

/ 

0/ 

// 

/ 

/ 0 ...... 

o----0----o----o _.-// 

30-34 35-39 40-44 45-49 50-54 

AGE BRACKET (yrs.) 

55-59 

100 

75 

CUMULATIVE 

% OF TOTAL 

NUMBER 

50 

25 

FIGURE 9. Each bar height represents the average maximum aerobic work capacity (MVO,) (in terms of VO,jkg 

bw) of the individuals within the specified age bracket. The figure within each bar is the number of individuals represented by that bar. The open circles connected by dashed lines represent the cumulative % of 

the total number of individuals at each successive age bracket. These data represent a total of 1270 individuals. 

37387 

10