heath y carter 67

7/28/2019 Heath y Carter 67

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A Modified Somatotype Method BARBARA HONEYMAN HEATH AND J. E. LINDSAY CARTER5 Via Joaqu in , M o n t e r e y , Cal i fornia and Sun Diego State Col lege,San Diego, Cal i fornia

ABSTRACT A new and improved somatotype method with universal application toboth sexes, for all ages and which i s reproducible, is justified, validated and described.Evidence is presented for extension of previous component rating scales. Data on 844male and female subjects from selected samples were used to develop and validateanthropometric scales for estimating the Heath component ratings. The deh iti onsand rating procedures for the new somatotype method are presented, with descriptionsof the anthropometric somatotype and the combined photoscopic and anthropometricsomatotype.

The purpose of this paper is to presenta somatotype method suitable for descrip-tion of individual variation in the humanspecies. To this end, we have adopted uni-versal rating scales and criteria which ap-ply to both sexes at all ages.We present a somatotype method whichconsists of Heaths (63) modificationsand adaptations of Parnells ( 5 8 ) M.4technique, which Heath and Carter (66)explored. We report the rationale for ex-tending and readjusting the rating scales,and have constructed tables to use withthe Heath somatotype method. The ex-tended and readjusted rating scales to-gether with these tables also enable inves-tigators to obtain reliable anthropometricsomatotype ratings.There are many somatotype studieswhich include extremes in one or more ofthe three somatotype components. Wehave carefully studied several of thesewhich emphasize the importance of usingone method suitable for all investigations.Seltzers (64) study of obese females dis-cusses the problem of adequate differentia-tion of a series in which the majority arerated seven in the first component (endo-morphy), when the criteria of Sheldonsseven-point scale are applied. In the Brit-ish Empire and Olympic Games series des-cribed by Tanner (64), there are athletesfrom many countries who are rated sevenrating units (seven) in the second com-ponent (mesomorphy) by Sheldons cri-teria; but they are conspicuously moremesomorphic than the examples of sec-ond component sevens in ATLAS OF MENAM. J. PHYS. NTHROP.,7: 57-74.

(Sheldon, 54). Heath found many malesamong the Manus in the Admirality IS-lands (Mead) who cannot reasonably berated by Sheldons second component cri-teria. Roberts and Bainbridge (63) foundit necessary to modify the Sheldon scale tofit the height/Vweight ratios obtained intheir study of the physiques of Nilotes.Third component ratings of seven werenot adequate for description and different-iation of the Nilote Series, in which therewas a high incidence of extremes in ecto-morphy. Irrespective of age and nutri-tional status, uniquely high third compon-ent ratings were confirmed by limb lengthand low total skinfold measurements aswell as by height/Vweight ratios higherthan any reported by Sheldon. Heath hasalso found high extremes in the first com-ponent and low extremes in the third com-ponent in studies of growth and develop-ment (Walker, 62); and significantchanges in somatotype ratings from yearto year are common for subjects in theMedford Growth Study (Clarke, 63).There is good evidence that selected sam-ples in this country and elsewhere will con-tinue to reveal somatotypes which do in-deed emphasize the need for a somatotypemethod to describe all human variation.Sheldons (40, 54) concept of quanti-fying three primary morphological com-ponents is original, useful and important.Despite lingering semantic problems, the

1 The authors are grateful to the Wenner-GrenFoundation for Anthropological Research, to the Na-tional Institutes of Health. arant CD 00140-01A1, andto the San Diego State College Foundation for grants.which in part supported this study.57


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58 BARBARA. HONEYMAN HEATH AND J. E. LINDSAY CARTERfour coined words - omatotype, endo-morphy, mesomorphy, ectomorphy- rewidely accepted in our vocabulary. Theyseem to convey reasonably similar and de-fensible meanings to those who use them.Standardized somatotype photographs, ac-curately measured and recorded stature,weight, and age are essential to precisedescription of human physical variationby means of somatotyping. However, anumber of investigators have found thedefinitions, criteria, and interpretations inSheldon's publications unsatisfactory. Sev-eral investigators (Cureton, '47; Hooton,'51; Parnell, '54, '58; Damon et al., '62;Sheldon, unpublished) have proposed var-ious adaptations and modifications ofsomatotype method, but none of these hasovercome the fundamental limitations.Heath ('63) proposed modifications to over-come some of the shortcomings of existingsystems. During the past 12 years Heathhas applied these modifications to soma-totype da ta involving approximately 15,000ratings, which have been used in over 30published studies. The studies includework associated with the Institute of Hu-man Development in Berkeley, the GesellInstitute, Harvard University, the MedfordGrowth Study, Institute of Child Health inLondon, University of Hawaii, San DiegoState, the American Museum of NaturalHistory, Ochanomizu University in Tokyo,and the Institute of Anthropology in Mos-cow. The subjects studied include longi-tudinal and cross-sectional data for bothsexes at all ages. There are large samplesof U. S . and English populations. Thereare also substantial samples of Eskimos,Japanese, Manus (Admiralty Islands), andathletes from 11 countries.Because the Heath method has alreadybeen widely applied, it is now necessary tostate the concepts and procedures of themethod together with recently added ob-jective elements. This statement distin-guishes the method from other methods,and facilitates comparative studies.

EXTENSION OF SOMATOTYPECOMPONENT SCALES

Heath ('63) indicated that componentscales should be open-ended in order toaccommodate variations greater than thoseobserved in Sheldon's ('40) pilot studies.

She studied selected series of somtatypephotographs to establish extentions of thescales and to accomodate extremes in allthree somatotype components. Serieswhich included three skinfold measure-ments - riceps (t), subscapular (ss),suprailiac (si),- ere rerated, relyingprimarily upon inspection and Heath's( '63 ) table of somatotypes and height/Vweight ratios, but considering relation-ships between total skinfold measurementsand first component ratings.The first sample consisted of 102 obesefemales (Seltzer, unpublished). First com-ponent ratings ranged from 5.0 to 19.0,without consideration of skinfold meas-urements. Although the first componentratings remained high, the range was from5.5 to 12.0 when skinfold measurementswere considered. The rerating changes areshown in table 1. This tabulation showsthat in almost 80% of cases there were norating changes in the second component,and in 99% there were no changes greaterthan plus-or-minus n e -h a l f . In more than92% of cases there were no changes in thethird component greater than o n e -h a l f .But in almost 79% of cases there werefirst component changes which loweredthe ratings by o n e -h a l f to seven .Similar procedures were applied to se-lected portions of the British Empire andOlympic Games series (Tanner, '64) andof the Manus series of males (Mead).These subseries were chosen because ofthe high incidence of height/Vweightratios below 12.20 and low skinfold totals.The differences in means between the firstand second ratings are as follows:

Athletes 1 s t c o m p . 2nd c o m p . 3rd c a m p .First ratin g 3.25 6.28 1.57Second rating 2.08 6.99 1.34

ManusFirst rating 2.32 6.50 1.60Second rating 1.64 6.71 1.63The data in table 1 reflect the differ-ences in patterns of rating changes inseries in which skinfold totals are highwith correspondingly high first componentratings, and in series in which skinfoldtotals are low with high second component

ratings. The magnitude of first componentchanges is of course greatest in the obeseseries. Although the means for total skin-


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A MODIFIED SOMATOTYPE METHOD 59TABLE 1

R at i ng c hange s in three series o f e x t re me somat o t y pe sFirst component

Change

+0.50.0

- .5- .0- .5-2.0- .5-3.0-3.5-4.0- .5-5.0- .5- .0- .0+1.5

0- .5- .0- .0- .5

+1.0

0-0.5- .0- .5- .0

I .~

Freq.~

7159111214865342321

102

91615216462

911103235

%

6.814.78.810.811.813.77.85.94.92.93.91.92.91.91o

99.9

Second component Third componentChange Freq. % Change Freq. %

A. Obese women (Seltzer, unpub.)

+0.5 7 6.8- .5 16 15.7 0.0 94 92.2-1.0 1 1.0 - .5 3 2.9

102 100.0 102 100.1

0.0 78 77.5 +0.5 5 4.9

B . Olympic and Empire Games atheletes (Tanner,'64)14.151.69.7 +2.0 1 1.6 $- 1.0 1 1.624.2 +1.5 7 11.3 +0.5 1 1.633.8 +1.0 15 24.2 0 32 51.59.7 +0.5 27 43.5 - .5 26 41.86.4 0 12 19.3 - .0 2 3.299.9 62 99.9 62 99.7

C. Manus males (Mead,unpub.)25.9 +1.5 1 2.9 +1.0 1 2.931.4 +1.0 4 11.4 +0.5 5 14.328.5 +0.5 13 37.1 0 16 45.88.6 0 17 48.5 - .5 8 22.65.7 - .0 5 14.399.9 35 99.9 35 99.9

folds are similar for the athletes and forthe Manus, 94% of the Manus skinfoldtotals range from 11.0 to 18. 9mm, whileonly 45% of the athletes have skinfoldtotals in this low range. Therefore thegreater changes in first and second com-ponent ratings in the athletes' series wereexpected.While the range of final second compo-nent ratings for the two male series wasfrom 5.0 to 9.5, it is noteworthy that ofthe combined total of 97 ratings, 37 ratingsare higher than any reported in ATLAS OFMEN. On this basis, it is apparent that bothskinfold values and height/Vweight ratios(as well as inspectional impressions) sup-port ratings higher than seven in the sec-ond component.

Detailed analysis of the rating changesmade in the TOPS series of obese womenand those made in the subseries of athletesand in the Manus series is presented be-cause these three subgroups include themost extreme somatotype ratings we haveobserved. These series offered an unusualopportunity to test two empirical scales o rtheir value and validity in objectifying so-matotype method. This analysis also sug-gested that it is desirable to readjust theheight/Vweight ratio distribution by wid-ening the intervals for one-rating changesat the low end of the scale; that it is feas-ible to extend the rating scales upward forthe first and second components; and thattotal skinfold values are acceptable forrating the first component. It also devel-


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60 BARBARA HONEYMAN HEATH AND J. E. LINDSAY CARTERoped that one-half ratings at the low endof the third component scale helped todifferentiate some subjects in these seriesand in studies of young cihldren (Walker,'62). Furthermore, Roberts and Bainbridge('63) found that ratings of eight and ninein the third component were appropriatefor the 11.7% of their Nilotic samplewhose height/qweight ratios were above14.80.In other words, it became evident thatanthropometric measurements, such as to-tal skinfold values, can be used to increasethe objectivity and reliability of somato-type ratings, and as guidelines in extensionand readjustment of rating scales.

DEVELOPMENT OF ANTHROPOMETRICSOMATOTYPE SCALES

Both Heath's and Sheldon's somatotypemethods have required long training be-cause inspectional skill is crucial to reli-able rating. The apparent interrelation-ships among skinfold measurements, totalbody fat, and first component ratings sug-gested the possibility of developing anthro-pometric somatotype scales which couldbe matched with the Heath method, there-by improving reliability and reproducibilityof somatotype rating.We used data for 844 subjects to developanthropornetric scales for estimating thecomponent ratings by the Heath method.Of the 844 subjects, we had suitable an-thropometric data together with standardsomatotype photographs for 597, and an-thropometric data only for 247 subjects.In addition to age, height, and weight, theanthropometric measurements consist ofsums of skinfolds- , ss, and si measure-ments- and in some cases diameters ofhumerus and femur, muscle girths of calfand biceps, and calf ( c ) skinfolds. Theages range from 14 years to the seventies;they represent many countries, races andracial combinations; they include extremesin each of the somatotype components,and a wide range of total skinfold meas-urements. The subject's series were as fol-lows:1. British Empire Games and Olympic Gamesathletes (Tanner, '64).N =166.Males from 23 countries.Ages 17 to 37 years.

2.

3.

4.

5.

6.

7.

Three skinfolds (t, ss, si), measured on leftside, with Harpenden caliper.Weight in kilograms and tenths, height inmillimeters.Standard somatotype photographs.Teachers and students of physical educa-Males and females.N =65 males, 66 females.Ages 18 to 52 years, males; ages 18 to 39,Three skinfolds ( t, ss , si) . measured on rightWeight in pounds, height in inches andStandard somatotype photographs.American college and university students(Haronian and Sugarman, '65).Males.N =102.Ages 17 to 28 years.Three skinfolds (t, ss, si), measured withLange caliper. Side measured, not re-ported.Weight in pounds, height in inches andtenths.Standard somatotype photographs.San Diego State (SDS) businessmen andMales (Carter, unpublished).N =19.Ages 28 to 59 years.Three skinfolds (t, ss, si), measured onWeight in pounds, height in inches and

tion, New Zealand (Carter, '64, '65).

females.side, Harpenden caliper.tenths.

teachers.

right side, Harpenden caliper.tenths.Standard somatotype photographs.TOPS series (Seltzer, unpublished data).

Females.N =102.Ages 1 7 to 69 years.Two skinfolds (t, ss) , with Lange caliper.Side measured, not reported.Weight in pounds, height in millimeters.Standard somatotype photographs.Manus series (Mead, unpublished data).Males and females.N =35 males, 42 females.Ages 18 years to seventies.Three skinfolds (t, ss, si), measured withHarpenden caliper, on left side.Standard somatotype photographs.Special series (Carter, unpublished data).( a ) Teacher, housewives, students, and ath-letes, primarily from the San Diegoarea.Females.N =196.Ages 14 to 69 years.Three skinfolds (t, ss, si ), measured onthe right side, Harpenden caliper.No photographs.

Obese American females.

(b) Physical education majors, San DiegoState.Females.N =19.Ages 21 to 27 years.


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A MODIFIED SOMATOTYPE METHOD 61Four skinfolds (t, ss , si , c ) , measuredNo photographs.on right side, Harpenden caliper.

(c ) U. S. Navy, Underwater demolitiontrainees, San Diego.Males.N =32.Ages 17 to 31 years.Four skinfolds (t, ss , si, c ) , measuredon right side, Harpenden caliper.No photographs.

First componen tThe first step in constructing a suitablescale (derived from skinfold values) tomatch Heath inspectional ratings was inestablishing the relationship, if any, be-tween sums of three skinfolds (t, ss, si)and the Heath ratings.There were available first componentratings on 501 male and female subjects,ages 16 to 69 years (series nos. 1, 2, 3, 5).Ratings were made prior to including skin-fold values in the rating method. The TOPSseries (no. 5) is particularly important be-cause of the uniquely high first component

ratings and uniquely low height/Vweightratios, and because of the high skinfoldmeasurements. In order to compare thisseries with the others, the data requiredspecial analysis because t and ss skinfoldsonly were measured. The sums of the twoskinfolds is higher for the majority of thesesubjects than the sums of the three skin-folds measured in the other series.In order to estimate the average contri-bution of si skinfold measurements toskinfold totals of three skinfolds, data onskinfold measurements for 262 females,ages 14 to 69 years were used. These in-cluded the New Zealand series (no. 2) andthe special series (no. 7a). For the com-bined series total skinfold measurementsranged from 15.8 mm to 113.3 mm, simeasurements ranged from 4.3 mm to43.1 mm. The mean for the si measure-ments was 13.3mm7or 30.9% contribu-tion of si measurements to the total ofthree measurements. Based upon the aboveestimate of percentage contribution of siskinfold measurements to total measure-ments the TOPS series total skinfoldsrange from 5 5m m to 157mm, with amean of 97.3mm.

Using the paired data from the 501 sub-jects the product-moment correlation wasr =0.95. This relationship indicates that

~-

Heath first component ratings and skinfoldscores were so similar that a skinfold scoresubstituted for a Heath rating would sac-rifice little or no accuracy, especially ingroup studies. Furthermore the test-retestreliabilities for skinfold measurements are0.90-0.96, and test-retest reliabilities forHeath ratings are approximately 0.92. Itis therefore unlikely that a higher correla-tion could be obtained.Figure 1 shows in graphic form theessentially linear relationship between firstcomponent ratings and skinfold totals forthe combined male and female series. Themedians were plotted, because at somerating points the distributions appearedslightly skewed. Inconsistencies betweenone-half ratings shown in figure 1 may bedue in part to one or more of the followingfactors: (1) Use of different calipers indifferent series; (2) measurements madeon the right side in some series, on theleft in others; (3) first component ratingsmade by Heath at different times; (4) pos-sible differences in reliabilities of meas-urements, especially in the case of highskinfold totals; (5) small numbers of ob-servations for some rating values; and per-haps most important, (6 ) limitations inthe Heath ('63) height/Yweight ratio tablefor very low ratios. This last point indi-cated that the distribution of somatotypesand height/Vweight ratios required modi-fication- specially for ratios lower than12.00.A scale for obtaining first componentratings from total skinfolds was con-structed, employing the following pointsas guidelines:1. Skinfold distributions are positivelyskewed.2. Heath's first component scale is posi-tively skewed.3. Small increments in skinfolds areeasily observed on inspection of photo-graphs of subjects low in the first compo-nent; but small increments in skinfoldsare not easily observed in subjects high inthe first component. In other words, thepercentage of increment in total skinfoldsbecomes more important than absolute in-crements in cases of high first componentratings.4. If reasonable error in total skinfoldmeasurements is -t 5% , then increments


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BARBARA HONEYMAN HEATH AND J. E. LINDSAY CARTER

0 s

W

00

. e

0

0#

e

E3:.95N =5-01=Med im of disf r ibuf ianm' each rafiny value.

Fig. 1 First component ratings by Heath versus sum of three skinfolds (triceps, subscapular, su-prailiac).between rating units for the first compo-nent must be 10% or more of total skin-folds.5. In constructing a scale of total skin-folds the increments between first compo-nent rating units should be established soas to meet the criterion of locating 90%or more of the component ratings withinplus-minus one-half.6. Since the specific gravity of fat islower than that of bone, muscle and otherbody constituents, a greater volume of f atis required for increases in weight and cor-responding decreases in height/Vweightratios.The scale so constructed is shown in theupper part of figure 2. The mid-points ofthe total skinfold values for each first com-ponent rating unit are shown in figure 3.The data show that there are increasingamounts of increase in total skinfold

values, but decreasing percentages of in-crease. The lowest percentages of increaselie between one-half intervals from ratingsof seven and me- hal f and above. Here thepercentages lie between 9% and 10%.Table 2 shows the distribution of so-matotypes and height/Vweight ratios, re-adjusted so that intervals between onerating changes are greater for ratios lowerthan 12.00. At the same time the upperend of the table was reviewed for accom-modation of subjects with unusually high

Fig. 2 The Heath-Carter somatotype ratingfo rm. The F-scale fo r arriving at the first compo-nent rating is the upper scale. The M-scale forarriving at the second component rating is themiddle scale. The Lscale for arriving at the thirdcomponent rating is the lower scale. Data andprocedures for arriving at an anthropometric so-matotype 4-5-21/2 are illustrated.


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64 BARBARA HONEYMAN HEATH AND J. E. LINDSAY CARTERTABLE 2

Distribution of somatotypes on the criterion of he i gh t / V w e i gh t , f o r both sexes and all agesRatio Somatotypes15.4015.2015.0014.8014.6014.4014.2014.0013.8013.6013.4013.2013.00

12.80

12.6012.4012.2012.00

11.70

11.40

11.0010.50

10.00

9.50

9.00

1-1-91-1-81-1-71-2-7,2-1-71-2-61-3-6,1%-3-6%2-2-62-2-511/2-21/2-52-3-5,3-2-5,2?~'!2-3-5?h145 ,4-1-53 -3 4 >31/3-24/~-5,2-4-5,4-2-54-2-4,3-3-4,21/2-31/2-41 - 5 4 , 2 4 41-5-3,11/2-5-3%4-2% -3?h2-5-3,5-2-3,&3-3,2'h-5-3%1M-5%-3,5-%-3,1-6-3,3-4-36-1-2,l-6-22-5-2,5-2-22-6-2,44-27-1-2,1-7-2,6-2-25-3-2,3-5-27-1-1,l-7-1,6-212-Gl7-2-1,2-7-1,6-3-13-6-1,541,4-5-17-3-1,3-7-1641,4-6-1,5-5-1741,8-3-1,9-2-1,3-8-14-7-1,5-6-1,6-5-18-4-1,9-3-1,10-2-13-9-1,4-8-1,5-7-1,6-6-19-4-1,lO-3-1,114-15-8-1,6-7-1,7-6-1,8-5-1104-1,11-3-1,1~5-18-61,7-7-1,6-8-1,5-9-111-4-1,12-3-1,1&5-16-9-1,7-8-1,8-7-112-4-1,13-3-1,11-5-1,lO-6-18-8-113-4-1,14-3-1,10-7-1,11-6-112-5-114-4-1,13-5-1,12-G1,11-7-1

1-2-91-2-8, l-21/2-81/22-2-7,1-3-723-7,3-2-72-3-6,3-2-6l V ~ 3 ~ h - 63-3-6,4-2-62% -3% -6

21/2-41/2-53-4-5,5-2-5,4-3-52-54,34-4,31/2-3%-45-2-4,4-3-4,21/341/2-44-4-45-343-5-46-2-3,2-6-344-3,5-3-33-5-36-3-3,3-6-354-3,4-5-3


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A MODIFIED SOMATOTYPE METHOD 65

Fig. 3 Mid-points of the total skinfold values for each first component rating uni t on the F-scale.height/Vweight ratios and third compo-nent ratings higher than seven. Table 2was constructed so that the intervals forheight/Vweight ratios from 12.00 down-ward increased in a somewhat geometricprogression. For each one rating changethe intervals increase from 0.20 through0.30, 0.40, to 0.50.Validat ion of the anthropometric scale(F-scale) for the f irst component . Heathrerated 414 subjects (series nos. 1, 2, 3,4) using the Heath method ('63) togetherwith the readjusted height/Vweight table(table 2), and with knowledge of totalskinfolds. Carter independently establishedthe first component ratings from the F-scale. The mean difference between theHeath rating and the F-scale rating, thereliability coefficient ( xy), he percentageagreement plus or minus one-half , and thecomponent range of Heath's ratings arepresented fo r each series and fo r the meanof the series in table 3 . The data indicatethat the mean differences are small, the

reliability and percentage agreement arehigh, and that the F-scale is an excellenttool for estimating the Heath rating forfirst component values ranging from oneto seven and one-hal f . These values forcomponent estimation are better thanthose reported in the literature as reviewedby Heath and Carter ('66).Data on the obese females(series no. 5) provide our only informa-tion about the F-scale and Heath ratingsabove seven and one-hal f . A s seen fromtable 3 the correspondence between theratings is not good. Considering the needfor estimating total skinfolds for thisseries, the unknown reliability of theskinfolds, the lack of muscle and bonemeasurements to estimate the second com-ponent, and the increasing variability ofskinfolds at higher values, it is not sur-prising that the agreement with the Heathrating is poorer than at lower levels on thefirst component scale. The percentageagreement plus OT m i n u s m e is 70%, and

C o m m e n t .


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66 BARBARA HONEYMAN HEATH AND J. E. LINDSAY CARTERTABLE 3

Compar i sons of th e cr i t er ion ra t ing a nd sca le ra t ing f o r f i r s t and th i rd somato type componentsFirst component Third component

Series Diff. Diff.N Heath- rxy "u$ip Range N 1 Heath- rXy "/",zi:,ty"angeF-scale L-scale

AthletesMales17-37 years 162 -0.04 0.94 100 1 -437/2 155 -0.27 0.95 87.8 142-6N.Z.P.E.Males and females18-52 years 131 0.00 0.97 97.7 11/2-5?h 128 -0.15 0.91 95.3 1-5U. S. CollegeMales17-28 years 102 -0.09 0.97 96.1 1 -7?h 100 SO.11 0.93 90.0 1-6San Diego StateMales28-59 years 19 -0.19 0.96 84.2 1%-6 14 $0.35 0.94 85.6 1 - 4Mean ofabove series17-59 years 414 -0.04 0.98 97.6 1 -7% 397 -0.22 0.98 90.7 V2-6TOPSFemales - - - - -17-69 years 102 Jr0.36 0.68 48.0 51/2-12ManusFemales18-70+ years 42 1-0.21 0.90 95.2 1 4% 26 -0.12 0.64 85.0 1-3%1 Subjects with height/+- ratios of 12.00 or more.

improves to 84% and 94% for plus OTminus one and one -hal f and tw o respec-tively. Nevertheless, Heath found the skin-folds extremely valuable in assigning herrating. It would appear that greater re-liance must be placed on the photoscopicrating at ratings of eight to twelve in thefirst component.With reference to the Manus females(series no. 6), it is interesting to observethat, although 48% of the group werepregnant, their total skinfolds (mean =21.6mm) were very low for women, andthat the reliability ( r =0.90) and the per-centage agreement plus or mi nu s one -ha lf(95.2% were high. This suggests thateven under conditions of pregnancy theF-scale is still a useful indicator of endo-morphy.Since the use of the three skinfolds hadbeen well established by Parnell ('54, '58),and many studies have used these meas-urements there seemed to be no good rea-son for changing the procedure. A questiondoes arise, however, as to the use of theF-scale values for the aged, very small andvery tall persons. Based on his studies and

those of others, Brozek ('65, p. 6) con-cluded that skinfold compressibility de-creases with age. In tall subjects (74inches or more) one obtains proportionallylarger skinfolds simply because the subjectis large (Mayer, '59). Present data doesnot permit the F-scale to be used withsmall children but work is under way todevelop scales for these groups. In thisconnection, consideration of Parnell's ('65)''total lean weight" with height correctionsseems to be appropriate. In practice, wefind the F-scale satisfactory for mostheights from 60 inches and more. Thelimitations of very high skinfolds, com-pressibility of skinfolds, and size of sub-jects can be allowed for in the photoscopicrating.Conclusion. An objective and validscale which meets acceptable criteria hasbeen developed for estimating Heath's firstcomponent rating.

T he Second componentIn a previous article, Heath and Carter('66) examined the relationships betweenHeath's ratings and Parnell's ratings based


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A MODIFIED SOMATOTYPE METHOD 67on the M.4 deviation chart. The authorsfound poorer relationships on the secondthan on the first and third components,and they also noted that with older sub-jects the differences would likely be greateras Parnells scales are age corrected. Sincethere were different patterns between themales and females on the second compo-nent and since the initial M.4 mesomorphyestimate is corrected for neither age, sex,nor fat, the addition of older subjects anda comparison of initial and final M.4 rat-ings with Heath ratings was suggested.Initial and final M.4 data and Heathratings were available on series nos. 2 and4. Comparisons were made among threegroups, N.Z. males, N.Z. females, andS .D.S . males. In five of the six compari-sons the mean Heath rating was higher by0.10 to 0.54; percentage ratings p lus orm i n u s o n e- h al f ranged from 58-89% ; hecorrelations ranged from r =0.69 to r =0.92; the percentage of high over low rat-ings ranged from 9-76%. Furthermore,Hea ths ratings on the second componentwere approximately one unit higher thanthe M.4 rating in series no. 3. An individ-ual analysis of selected photographs ineach series indicated that the correctionfor high total skinfolds had forced ambigu-ously low second component ratings formany of these physiques.Since the above observations showedthat there were considerable discrepancies,a solution was attempted by readjustingthe mesomorphy scale and changing themethod of skinfold correction. We ac-cept Parnells general principle that givenamounts of mesomorphy will be propor-tional to height, since somatotype is ameasure of shape, not size- he taller theperson the larger the musculoskeletal di-mensions must be to maintain the samelevel of the second component. Althoughcertain limitations have been cited, theanthropometric measures (humerus andfemur biepicondylar diameters, flexed armand calf girths) and scale adopted seemto be the best simple indicator of meso-morphy which we have (apart from thephotograph). Keeping the basic structureof the M.4 chart for the second componentintact, the following modifications were

The first modification was the movingof the height values one column to the left,thus effecting a one-half increase in thesecond component. The second modifica-tion was a direct skinfold correction to thelimb circumferences. The t skinfold, butnot the c skinfold, has been included inthe M.4 measurements in the past. In ourmodificatoin a medial c skinfold, as sug-gested by Brozek (60) is used for the cor-rection of c girth. The simplest and mostpractical correction appears to be that ofsubtracting the skinfold value from therelated limb girth be fore circling the ap-propriate value in the muscularity table(see center of figure 2 ) . Although this isnot claimed to be a perfect correctionit is at least in the right direction and isapplied only to the measurements whichencompass skinfolds. This procedure alsoeliminates the age correction incorporatedin Parnells M.4 chart.Val ida t ion of th e anthropometr ic scale(M-scale) f o r the second component. Al-though the adjusted scale (M-scale) forthe second component was available, indi-vidual validation against the Heath scalewas limited by the absence of c skinfoldson the rated series. However, with ade-quate estimates for c skinfolds availablefrom other samples the M-scale was ap-plied to the means for series number 2(male and female), series number 3, andon an individual basis to series number 4.Estimates for the c skinfolds for the fe-males were taken from measurements onseries number 7b, while those for the maleswere taken from measurements on seriesnumber 7c. As the means for the sum ofthree skinfolds of the subjects in seriesnumbers 7b and 7c differed slightly fromthe means of series numbers 2 and 3, apercentage correction was applied to themean c skinfold before calculating the sec-ond component.In each of four comparisons, betweenthe Heath rating and the M.4 rating andthe Heath rating and the M-scale, themean differences were reduced consider-ably. The Heath ratings were still slightlyhigh in three of the comparisons- .11fo r the N.Z. females, 0.16 for the N.Z.males, and 0.52 for series number 3. How-ever, for series number 4 the mean differ-made. ence. was reduced from 0.35 to zero, with


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68 BA R BA R A H O N EY MA N H EA TH A N D J. E. LINDSAY CARTERan r =0.94, and 90% agreement withinone-half.The Heath ratings on the secondcomponent ranged from tw o to seven.Comment. When Heath and Carter('66) used the Heath method for ratingthe second component, they reported bet-ter agreements than different raters usingother methods. The difficulty then seemsto stem from the anthropometric measuresand the scales of their values, Anotherlimitation in the M-scale is that, since fatis not distributed evenly around a limb,the double skinfold is at best an estimatedcorrection. The alternatives of multipleskinfolds or cross-sectional analysis appearto be impractical for the limited gains pos-sible. Empirically, the present M-scale ap-pears to be more satisfactory for obtaininga Heath rating than the M.4 chart.Conclusions. 1. The Parnell M .4 as-sessment of the second component is nota satisfactory estimate of the Heath rating.2. The present M-scale is the preferredmethod for estimating the Heath rating forthe second component in group studies,until the method can be further refined.3 . More reliance on the photographand height/Vweight ratio table is indi-cated for the second component ratingthan for the other two components overthe same range.

The Third componentHeath's revised distribution of somato-

types for height/Vwwt ratios (table 2)shows two important features. To beginwith, for the ratio 12.00 and above, thethird component values appear to rise withthe ratio in a linear fashion with no morethan two rating values appearing at eachratio. Secondly, for height/Vweight ratiosbelow 12.00 there seems to be an evenchance of the third component value beingeither one-half or one. Hence it can beseen that table 2 alone cannot be used togive the third component rating.Since the distribution of somatotypes intable 2 represent a well established empiri-cal population, the use of a regressionequation to predict the third componentvalue from the height/Vweight ratio sug-gested itself. Accordingly, the third com-ponent values ( Y ) associated with givenheight/Vweight ratios from 12.00 to 15.00

were plotted (fig. 4 ). For the 121 somato-types the correlation was r =0.97, and theregression equation for predicting Y fromX is:The majority of the somatotypes are with-in a half unit of the regression line andall are within the one unit boundaries.Using the above equation a scale (L-scale)was constructed for estimating the Heathrating (see bottom of figure 2).Validation of the anthropometric scale(L-scale)for the third component. Ratingsmade by Heath, prior to the developmentof the L-scale, fo r the 397 subjects in se-ries numbers 1, 2, 3 , and 4, whose height/Vweight ratios were 12.00 or more wereused in the validation. Carter indepen-dently determined the third componentratings from the L-scale. The mean differ-ence between the Heath rating and theL-scale rating, the reliability coefficient( xy, the percentage agreement plus orminus one-half,and the component rangeof Heath's ratings are presented for eachseries and for the mean of the series intable 3. Although the mean difference of- .22 shows that Heath rated slightlylower than the L-scale, the reliability (r =0.98) and percentage agreement (91% )are high for the range of me-half to six onthe third component.The lower Heath rating ofapproximately me-fi f th on the third com-ponent is attributed to the ratings on theseries of athletes as the mean differencebefore adding this series was zero. It a ppeared that an unconscious rater biasfavoring the lower of the possible ratingsin table 2 was operating at the time ofrating.Although there are no subjects with rat-ings of seven or above in the third compo-nent in our present series, observation ofother data indicates that the L-scale is anadequate estimator of the Heath rating atthese high levels. When compared to theL-scale, the height/vweight ratio pointsestablished by Roberts and Bainbridge ('63)for somatotypes 1-2-8 (14.70), 1-1-8(15.00), and 1-1-9 (15.20) are slightlylow.Since no further data to improve theprediction is available from table 2 or

Y =2.42X - 8.58

Comment.


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A MODIFIED SOMATOTYPE METHOD 69

Fig. 4 Height/q- ratios versus third component ratings by Heath. The half unit and oneuni t boundaries from t he regression line are shown.the L-scale, those subjects with height/Vweight ratios below 12.00 are rated m e-h a l f . When the somatotype photograph isavailable the following rule should be ap-plied :If the L-scale rating is o n e - h a l f , butthe subject shows slight tendencies

towards linearity or elongation of thelimbs or their segments, a rating ofone should be assigned.The data on the 26 Manus women (se-

ries no. 6) who had height/Vweight ratiosof 12.00 or greater is included to illustratea dilemma in rating the third component.Fourteen of the 26 (54%) were in vary-ing stages or pregnancy. Since all had lowskinfold totals the only evidence of excessweight was the localized abdominal pro-tuberance. This leads to a conflict betweenthe photoscopic impression and the height/Vweight ratio which must be resolved by

the rater, and appears to account fo r thelower reliability and percentage agreementthan in the other samples. No data is pre-sented on the obese females (series no. 5)as 90% of the subjects had height/Vweight ratios of 12.00 or less.1. An objective and validscale which meets acceptable criteria hasbeen developed for estimating Heathsthird component rating.2. Better differentiation between a cme-h a l f and m e rating can be obtained withthe aid of the photograph.The foregoing material has describedthe development of anthropometric scalesfor estimating the Heath rating. The scalesare considered highly satisfactory for thefirst and third components, and satisfac-tory for the second component. The onlyexception appears to be that the scales areless reliable for subjects very high in the

Conclusions.


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70 BARBARA HONEYMAN HEATH AND J. E. LINDSAY CARTERfirst component (8-22) and very low inthe third component.The following material is a descriptionof the currently used Heath-Carter somato-type rating method, giving definitions, datarequired, and the rating procedures.

THE HEATH-CARTER SOMATOTYPERATING METHOD

Definitions1. A somatotype is a description of pres-ent morphological conformation. It is ex-pressed in a three-numeral rating, consist-ing of three sequential numerals, alwaysrecorded in the same order. Each numeralrepresents evaluation of one of the three

primary components of physique which de-scribe individual variations in human mor-phology and composition.2. First c o m p o n e n t (or endomorphy)refers to relative f a t n e s s in individualphysiques; it also refers to relative Zean-n e s s . That is, first component ratings areevaluations of degrees of fatness which lieon a continuum from the lowest recordedvalues to the highest recorded values.3. Second component (or mesomorphy)refers to relative musculoskeletal develop-ment. Second component ratings are eval-uations of musculoskeletal developmentwhich lie on a continuum from lowest tohighest degrees recorded. The second com-ponent can be thought of a s Lean BodyMass- n in v i m entity consisting of themusculoskeletal system, the soft organs,and total body fluids, or the whole bodyless nonessential fat (Behnke, '53).4. T h i r d c o m p o n e n t (o r ectomorphy)refers to relative linearity of individualphysiques. Third component ratings arebased largely, but not entirely, on height/Vweight ratios. Height/Vweight ratios andthird component ratings are closely re-lated, so that at the low ends of their dis-tributions both connote relative shortnessof the several body segments, and the highends connote elongation or linearity of theseveral body segments. Ratings evaluatethe form and degree of longitudinal distri-bution of the first and second components.Our definitions and concepts of thethree somatotype components are derivedin part from interpretations of studies ofbody composition. These include estimates

of total body fat , total body water, and leanbody weight (Behnke, '53, '59, '61, '63;Keys and Brozek, '53).We emphasize that extremes in eachcomponent are found at both ends of con-tinua. That is, low first component ratingssignify physiques with little nonessentialfat, while high ratings signify high degreesof nonessential fat. Low second compo-nent ratings signify light skeletal framesand little muscle relief, while high ratingssignify marked musculoskeletal develop-ment, as in many athletes. Low third com-ponent ratings signify short extremitiesand low height/+- ratios, while highratings signify linearity of body segmentsand of the body as a whole, together withhigh height/$- ratios. Extremes atboth ends of all three somatotype compo-nent ranges connote rarity of occurrence.In the majority of cases ratings of all threecomponents tend to be nearer to the mid-range than at the extremes.

The rating scalesRatings of each component theoreticallybegin at zero and have no arbitrary endpoint. In practice, no ratings less than

one-half are given. One-half intervals arerated when appropriate in reconciling ofinspectional criteria, anthropometric data,and height/+- ratios. The same rat-ing scales, height/#- ratio criteria,scale of skinfold values, and scaIe of valuesfor bone diameters and muscle girths areapplied, with limited reservations only, toboth sexes at all ages.

The data1. Standard 5 X 7 in somatotype photo-

graph (Sheldon, '54, Appendix pp. 345-349; Tanner, '49; Dupertius, '63).2. Measurements: (see Parnell, '58)Age- ears and monthsHeight-in millimeters, o r in inchesand tenthsWeight- in kilograms and tenths, ori n pounds and half-poundsSkinfolds- riceps ( t ) , subscapular(ss) , suprailiac (si), calf ( c ) (meas-ured on the right side, preferablywith Harpenden caliper) in milli-meters and tenthsBone diameters -humerus and femur,

in millimetersMuscle girths- flexed arm, c, in milli-meters


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HEIGHTIn.

----10.5--

A MODIFIED SOMATOTYPE METHOD

10.0

9.5

9.0

WEIGHTLbr.90

95

100

105

110

1I5

71

Fig. 5 Nomograph for determining height over cube root of weight when height is knownin inches and weight in pounds.


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72 BARBARA HONEYMAN HEATH AND J. E. LINDSAY CARTERProcedures fo r obtainingsomatotype ratings

Essentially there are three ways of ob-taining the somatotype rating. First, onecan obtain an anthropometric somatotyperating, without having a somatotype pho-tograph, when all of the recommendedmeasurements have been taken. Second,it is possible for experienced somatotypersto make reliable photoscopic or inspec-tional ratings, when age, height, weight,and a standard somatotype photograph areavailable. The third method is the Heath-Carter somatotype rating which combinesthe previous two procedures.The an th rq me tr ic somatotype ( f i g . 2).Record the subject information and themeasurements in the spaces provided onthe somatotype rating form.a To obtain thefirst component rating, sum the three skin-folds (t, ss, si), circle the closest value inthe F-scale, and then circle the ratingvalue for that column. To obtain the sec-ond component rating, mark the point ofthe subjects height on the height scale.For each bone diameter circle the figurein the proper row which is nearest theexact measurement. Subtract the t skin-fold from the biceps girth, and the c skin-fold from the c girth, before circling thefigure in the proper row which is nearestthe measurement. Dealing only with col-umns, mark the point that is the averageof the circled figures for the diameters andgirths only. Count the number of columns(and fractions) by which this average de-viates right or left from the marked height,then move this number of columns rightor left from the four in the second compo-nent rating and circle the closest ratingvalue. The third component rating is ob-tained by finding the height/V= fromthe nomograph (fig. 5) and recording it,circling the closest value in the L-scale,and circling the rating value for that col-umn. Finally, the values for each compo-nent rating scale are recorded after An-thropometric Somatotype at the bottom ofthe form (fig. 2). An example using theabove procedure is shown on the ratingform.The photoscqic somutotype. As men-tioned above, long training and experience

are required for obtaining reliable somato-type ratings when the data do not includethe recommended anthropometric meas-urements. Inexperienced investigators findthat the lack of a handbook of somatotypemethod makes accurate rating difficult.The Heath (63)method depends primarilyupon reference to table 2, the distributionof somatotypes and height/V- ratios,and upon wide experience with recogniz-ing the approximate rating values appro-priate for each component. The finalrating is given after reconciling height/V w riteria and inspectional criteria.When the subjects are adult males it isuseful to compare photographs with ap-parent prototypes at about age 18 as shownin ATLAS OF MEN (Sheldon, 54).The Heath-Curter somatotype. In orderto give a Heath-Carter somatotype ratingthe following are needed:1. The somatotype photograph.2. The Heath-Carter Somatotype RatingForm (fig. 2), upon which the data for thesubject have been recorded.3. Table 2, the distribution of height/3 ratios and somatotype ratings.In order to arrive at a final somatotyperating one must keep in mind that the so-matotype photograph is a record of all themorphological characteristics which havebeen sampled by the anthropometric meas-urements. The objective is to reconcile thecriteria of the height/+- ratio, thecriteria of photographic inspection, andthe estimated anthropometric somatotype.The number of steps and the length oftime required for obtaining the objectivevary from subject to subject and from raterto rater.

When one somatotype component isclearly dominant, the table of somatotypesand height/Vweight ratios alone narrowsthe possible choice of ratings. Height/f7 ratios identify extremes in thefirst and third components. It is thereforeclear that the greatest difficulties are en-countered in arriving at final ratings ofthe second component for midrange so-matotypes, whose height/- ratiosare also midrange. In most cases it is best

2 Printed copies of the somatotype rating form maybe ordered from Dr. J. E. L. Carter, San Diego State,San Diego, California. 92115.


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A MODIFIED SOMATOTYPE METHOD 73to compare inspectional impressions andfirst component estimates obtained fromthe F-scale, then do the same for the L-scale. Using table 2 and the reconciledratings for the first and third componentsidentify the physiques at (or close to) thesubjects height/Vweight ratio which havesimilar first and third component ratings.Check the inspectional inipressions of thesecond component with the M-scale, andfinally, reconcile the photoscopic impres-sions, the anthropometric somatotype, andtable 2, then assign the final rating.For many physiques there are no differ-ences between the anthropometric somato-type and the final combined rating. Whenthere are differences, these are most likelyto be one-half differences, except for sub-jects high in endomorphy where the differ-ence may sometimes be as large as me.

CONCLUSIONA new and improved somatotype methodwhich is reproducible has been justified,validated, and described.

DISCUSSIONThe preceding operational definitionsand procedures have evolved over manyyears of experience with both anthropo-metric and photoscopic ratings. The systemas it is now applied is useful and logical.Over the years it has become increasinglyobvious to those attempting to use somato-typing as a sound tool of investigation thatit is more important to record what thesomatotype is at a given time than to pre-dict what the subject will be or might be.We unequivocally state that the opera-tional definition of somatotype as givenabove is a descriptive device for recordingpresent and future status (i.e., change),providing that actual ratings are made o nthe same scale at different points in time.In spite of Sheldons (40, 54) protesta-tions to the contrary, his morphogeno-type is neither dynamic nor useful in itspresent form. In his discussion of the mor-phogenotype and morphophenotype theimpression Sheldon gives is that somato-type implies predictability and that isgood, and that phenotype does not implypredictability and that is bad. Althoughprediction of data on a parameter a t adifferent point in time is of value, the pre-

ferred method in most sciences is to meas-ure exactly what the data are at that time.For example, although the genetic basisfor stature is recognized and prediction ofadult stature from certain ages is reason-ably accurate, one still m e a s u r e s statureperiodically against the sam e scale and cer-tainly does not use the age-nonned scalesas the measuring scale. Furthermore, asthe word phenotype is not specifk to so-matotyping but has general use in biology,we suggest that its use as a noun be dis-continued. Sheldons age-weight correctedscales were designed primarily to supportthe premise that the somatotype is perma-nent. The validity of these age-weight cor-rected tables is questionable because theywere constructed by interpolation and ex-trapolation of weight histories which inthemselves are often unreliable (see Da-mon, 65). The data also were drawn al-most entirely from cross-sectional studies,which with secular changes in heightand weight are by now far outdated.Such scales as Sheldons are to be re-garded purely as percentile or standardscales which slide to match each other atdifferent age levels and are not suitablefor observing change.

ACKNOWLEDGMENTSThe authors express their appreciationto Drs. Margaret Mead, James Tanner,Carl Seltzer, Frank Haronian, and ArthurSugarman for use of some of their ma-terials. Thanks also is extended to CarolynMcLure, Sheila DeWoskin, Joan Westlake,and Joanne Climie for assistance in gath-ering data on some of the female subjects.

LITERATURE CITEDBehnke, A. R. 1953 The relationship of leanbody weight to metabolism and some conse-quent systematization. Ann. N. Y. Acad. Sci.,

1959 The estimation of lean bodyweight from skeletal measurements. Hum.Biol., 31: 295-315.1961 Quantitative assessment of bodybuild. J. Appl. Physiol., 16: 960-968.1963 Anthropometric evaluation ofbody composition throughout life. Ann. N.Y.Acad. Sci., 110: 450-464.Brozek,J. 1960 The measurement of body com-position. In: A Handbook of Anthropometry, byM. F. A. Montagu. Charles C Thomas, Spring-field, Illinois.

56: 1095-1142.


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74 BARBARA HONEYMAN HEATH AND J. E. LINDSAY CARTER1965 Methods for the study of bodycomposition: Some recent advances an d devel-opments. In: Human Body Composition. J.Brozek, ed. Pergamon Press, New York.Carter, J. E. L. 1964 Physiques of male physi-cal education teachers i n training. J. Phys. Ed.

Assn. Gt. Brit. and N. Irld., 169: 66-76.Physiques of female physical ed-ucation teachers in training. J. Phys. Ed. Assn.Gt. Brit. and N. Irld.. 170: 6-16.1965

Carter, J. E. L. (Unpubl ished).Clarke, H. H. (Ed. ) 1963 The Medford, Ore-gon, Boys Growth Study. Curriculum Bulletinno. 238, University of Oregon, Eugene, Oregon,Nov.Cureton, T. K., Jr. 1947 Physical Fitness Ap-praisal and Guidance. T h e C. V. Mosby Co.,St. Louis.Damon, A. 1965 Adult weight gain, accuracyof stated weight, and their implications forconstitutional anthropology. Am. J. Phys. An-throp., 23: 306-311.Damon, A., H. K. Bleibtreu, 0. Elliot and E. Giles1962 Predicting somatotype from body meas-urcments. Am. J. Phys. Anthrop., 20: 461-474.Dupertuis, C. W. 1963 In: AnthropometricSurvey of Turkey, Greece, and Italy. H. T. E.Hertzberg, E. Churchill, C. W . Dupertuis, R. M.White and A. Damon, eds. Pergamon Press,New York.Haronian, F., and A. A. Sugarman 1965 Acomparison of Sheldons and Parnells methodsfor quant ifying morphological differences. Am.J. Phys. Anthrop., 23: 135-142.Heath. 3. H. 1963 Need for modification ofsomatotype methodology. Am. J. Phys. Anthrop.,

1966 A com-21: 227-233.Heath, B . H., and J. E. L. Carterparison of somatotype methods. Am. J. Phys.Anthrop., 24 : 87-99.Hooton, E. A. 1951 Handbook of Body Typesin the United States Army. Department of An-

thropology, Harvard University, Cambridge,Mass.Keys, A., and J. Brozek 1953 Body fa t in adultman. Physiol. Rev., 33: 245-325.Mayer, J. 1959 Obesity: diagnosis. Postgrad.Med., 25: 469475.Mead, M. (Unpublished da ta. )Parnell, R. W. 1954 Somatotvnine bv Dhvsical_ Ianthropometry. Am. J. Phis. Xnthrop., 12:209-239.~~ ~~~ 1958 Behaviour and Physique. EdwardArnold (Publishers) Ltd., London.1965 Huma n size, shape, and compo-sition. In : Hu ma n Body Composition. J. Brozek,ed. Pergamon Press, New York.Roberts, D. F., and D. R. Bainbridge 1963Nilotic physique. Am. J. Phys. Anthrop., 21:Seltzer, C. C. (Unpublished.)Seltzer, C. C., and J. Mayer 1964 Body buildand obesity-Who are obese? J . Am. Med.

Assn., 189: 677-684.SheIdon, W. H. (Unpublished.) As cited inHaronian and Sugarman, see above.Sheldon, W. H., C. W. Dupertuis and E. McDer-mott 1954 Atlas of Men. Harper Bros., NewYork.Sheldon, W. H., S. S. Stevens and W. B. Tucker1940 The Varieties of Hu ma n Physique.Harper Bros., New York.Tanner, J. M. 1964 The Physique of the Olym-pic Athlete. George Allen and Unwin, London.Tanner, J. M., and J. S. Weiner 1949 The re-liability of the photogrammetric method of an-thropometry , with a description of a miniaturecamera technique. Am. J. Phys. Anthrop., 7:Walker, R. N. 1962 Body build and behaviourin young children. I. Body build and nurseryschool teachers ratings. Monographs of SOC.for Research in Child Dev., Serial no. 84, 27:No. 3.

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