Medial Calf Skinfolds Research Articles

Age trends in anthropometric characteristics among 6-9 years old Bengalee Hindu school girls of Kolkata, India

A cross-sectional study of 431 6-9 years old urban Bengalee Hindu schoolgirls of Kolkata, India, was undertaken to study age trends in anthropometric characteristics including regional and subcutaneous adiposity. The anthropometric variables measured included height, weight, sitting height (SH), waist (WC), hip (HPC), thigh (TC), mid-upper arm (MUAC) and medial calf (MC) circumferences as well as triceps (TSF), biceps (BSF), subscapular SUBSF), suprailliac (SUPSF) and medial calf (MCASF) skinfolds. The results revealed, that there was a significant increasing age trend for all the anthropometric variables including the two derived variables: body mass index (BMI) and subischial leg length (SLL). For all variables, the lowest and the highest means were observed at the age of 6 and 9 years, respectively. The maximum increase in weight, BMI, all linear measurements, WC and HPC were observed during the period 6-7 years of age. In general, all skinfolds recorded similar yearly increments. More importantly, this study clearly indicated that among Bengalee girls aged 6-9 years, the highest amount of linear growth (height, SH and SLL) was observed at 6 years of age. The overall adiposity (BMI) also recorded the maximum increment during this period. The unique data presented here can be used as reference values for urban Bengalee Hindu girls aged 6-9 years.

Changes in performance, skinfold thicknesses, and fat patterning after three years of intense athletic conditioning in high level runners

Objectives: To determine if the changes in specific skinfold sites induced by intense athletic conditioning over a three year period were associated with changes in running performance in high level...

Validação de métodos de estimativa da gordura corporal em portadores do HIV/Aids

To validate different methods for estimating HIV/Aids patients' body fat: total body skinfold thickness, central (trunk) skinfold thickness, peripheral (limb) skinfold thickness, waist circumference (WC) and waist-to-hip ratio (WHR). Dual-energy X-ray absorptiometry (DEXA) and computed tomography of the abdomen (CTA) were used as the gold standard. An analysis was done on 15 adult HIV/Aids patients (10 men and 5 women) who were being treated at an Aids clinic at a public university hospital, Sao Paulo, Brazil. Their total subcutaneous fat (TSF) was estimated from the sum of the thicknesses of the biceps, triceps, subscapular, midaxillary, suprailiac, abdominal and medial calf skinfolds. The central subcutaneous fat (CSF) was estimated by summing the subscapular, axillary, suprailiac and abdominal skinfold measurements. The peripheral subcutaneous fat (PSF) was estimated by summing the biceps, triceps and medial calf skinfold measurements. These were compared with Dexa. The WC, WHR and CSF were compared with CTA. In the statistical analysis, the Pearson correlation coefficient (r) and Mann-Whitney test were utilized. There was a correlation between fat mass measured by DEXA and by TSF, CSF and PSF, even after adjusting for age (r> or =0.80 for all). WC, WHR and CSF presented correlation with total abdominal fat measured by CTA, even after adjusting for age (r> or =0.80 for all). The methods for estimating body fat should be chosen according to the type of fat to be evaluated and can be used in research and healthcare services instead of DEXA and CTA for HIV/AIDS patients.

The Impact of School-Based Physical Education on Physical Activity Levels and Percent Body Fat

0724 Hypokinetic diseases, including rates of childhood obesity and Type II diabetes, are rising. Concurrently, the prevalence of school-based physical education programs is declining. The latest Surgeon General's Report targeted the decline in childhood physical activity with a recommendation to implement daily physical education classes in all schools. PURPOSE: The aim of this investigation was to determine if children exposed to daily school-based physical education possessed lower levels of percent body fat and achieved greater levels of daily physical activity than children attending weekly physical education classes. METHODS: Percent body fat percentage was calculated from triceps and medial calf skinfolds while physical activity was quantified via TriTrac accelerometers (R3D Research Ergometer) and averaged over a consecutive 3-day period. RESULTS: Data analyses revealed no statistically significant differences in percent body fat between the two groups. Children receiving daily physical education, however, had greater average movement in the transverse plane (P <.05). CONCLUSION: These data suggest that, in addition to the frequency of physical education, the content and quality of the physical education curriculum that children are exposed to must also be evaluated when the aim is to increase activity and ultimately, to improve health. Supported by the Charles L. Cahill Award for Faculty Research and Development at The University of North Carolina at Wilmington.

Percentage of fat adjusted for build in postmenarchal Venezuelan adolescents

Adolescence is an important period of life characterised by morphological and physiological changes that have health-related significance. In recent decades, the improved standard of living conditions, as well as a change in the pattern of intake and quality of food plus reduced levels of physical activity, have increased the levels of overweight and obesity within this age group. The current cross-sectional study was conducted on 82 postmenarchal girls aged 13–17 years, from the city of Caracas, Venezuela. The aim of the investigation was to examine the relationship between frame size and percentage of body fat. Biceps, triceps, subscapular and medial calf skinfolds, and bicondylar widths of the humerus and femur were included in the anthropometric survey. The equations of Slaughter et al. (1988) and two linear regression analyses with humerus and femur widths as independent variables were used. Percentage body fat had a low to moderate (p<0.05) correlation with humerus (r=0.39) and femur (r=0.50) width. The results suggest that build, particularly as indicated by femur width may be a useful tool in the appraisal of adiposity in girls of these ages and may be of use in further research in other age groups.

Avaliação do estado nutricional de atletas de ginástica olímpica do Rio de Janeiro e São Paulo

Com o objetivo de avaliar o estado nutricional de atletas de ginástica olímpica, do sexo feminino, foram estudadas 46 ginastas, de 11 a 14 anos, pertencentes a clubes e academias das cidades do Rio de Janeiro e São Paulo. O estudo antropométrico envolveu medidas de massa corporal, estatura, dobras cutâneas e perímetros. Observou-se diferença significativa para as dobras cutâneas tricipital, suprailíaca, da coxa e da panturrilha e para o percentual de gordura (p&lt;0,05). Para o estudo dietético foram utilizados recordatório de 24 horas e registro alimentar de três dias. As ginastas apresentaram baixo consumo energético. A percentagem de carboidratos, 50% a 58%, e a ingestão protéica de 1,5 a 1,7 g/kg de peso mostraram-se baixa e adequada, respectivamente, frente ao proposto para atletas. O conteúdo de vitaminas foi satisfatório, com exceção do ácido fólico para as adolescentes cariocas. Os minerais julgados inadequados foram cálcio, magnésio, ferro e zinco. O estado nutricional de ferro não apresentou alterações.

Correcting calf girth discriminates the incidence of falling but not bone mass by broadband ultrasound attenuation in elderly female subjects

Calf circumference has been cited as an independent risk factor for hip fracture. Correcting this measured girth for subcutaneous adipose tissue or fluid accumulation provides a more valid estimate of lean tissue, but has not been reported in elderly populations. Two hundred eighty-eight randomly selected female volunteers, aged ≥70 years, were assessed by quantitative ultrasound (QUS) and clinical risk factors as part of a larger screening study for hip fracture risk. This involved measuring broadband ultrasound attenuation (BUA) and administering a structured risk factor questionnaire that included estimated daily skeletal loading (time standing or walking). Body mass index (BMI) was estimated using current body mass and height at age 25 years. Calf girth was measured using a standard anthropometric tape, the medial calf skinfold (a vertical fold at the point of maximum calf girth) was measured, and corrected calf girth (CCG) was calculated by subtracting the skinfold (in centimeters) multiplied by π from calf girth. Subjects were aged 76.9 ± 5.0 years, had BMIs of 24.3 ± 3.9 kg/m2, and spent an average of 5.5 ± 2.0 h on their feet each day. Age, current body mass, BMI calf girth, and CCG all correlated with BUA (p < 0.01). CCG correlated with hours on the feet (p < 0.05), whereas calf girth did not (p > 0.05). Dividing the sample into tertiles by these correlates of BUA and predicting BUA using stepwise regression revealed different predictors for each tertile. Of the total sample, 93 had fallen in the last 12 months, whereas 195 had not. Independent t-tests showed these groups to be similar in age, BMI, and calf girth (p > 0.05), but fallers spent less time on their feet each day, and had smaller CCG (p < 0.05). This suggests that larger calf muscles may be protective against falling—possibly as a result of enhanced stability or greater neuromuscular control.

The Interaction of Waist-Hip Ratio and Conicity Index with Subcutaneous Adiposity in Two Ethnic Groups: Native British and Migrant Pakistani Men

The objective of the present investigation was to evaluate the relationship between two indices of abdominal fatness, the waist-hip ratio (WHR) und conicity index (CI), with subcutaneous adiposity (5 trunk and 4 extremity skinfolds) in adult native British (n = 262) and migrant Pakistani (n = 100) men, resident in Peterborough, East Anglia, England. Both groups had similar body mass index (BMI), WHR and CI. Significant ethnic differences (age controlled) were observed in mean values for all trunk as well as forearm skinfolds between the two groups. The results indicated that, in general, there was no ethnic heterogeneity in the relationship (age controlled) of both the indices of abdominal adiposity with the skinfolds. However, the distributions, age, age2 and WHR controlled; and age, age2 and CI controlled, of subscapular (SUBSF), suprailiac (SUPSF), abdomen (ASF), midaxillary (MIDSF), chest (CSF), forearm (FSF) and medial calf (MCSF) skinfolds were significantly different between the two groups. Multiple regression analyses revealed that Pakistanis had significantly higher mean SUBSF, SUPSF, ASF, MIDSF, CSF and significantly lower mean FSF and MCSF than Whites, after controlling the effect of WHR. Similar significant ethnic differences were observed when the effect of CI was controlled for. This significant association of ethnicity remained even when the combined effects of WHR and CI were removed.

EVALUATION OF CARDIORESPIRATORY FITNESS FROM A 20-MINUTE STEADY STATE JOG INDEPENDENT OF BODY COMPOSITION IN ADOLESCENTS

The purpose of this study was to determine the relationship between sum of two-site (triceps and medial calf) skinfold thickness and performance on a 20-minute steady state jog (20MSSJ) test of cardiorespiratory function in adolescents. This study also evaluated the effect of adjusting 20MSSJ performances for skinfold thickness on the achievement of criterion-referenced standards for the 20MSSJ. Subjects were 75 adolescents (32 females and 43 males), ages 13–18 years. Following an eight-week conditioning period, each subject performed the 20MSSJ on an indoor running surface. Performances were recorded to the nearest tenth of a mile. Twenty-eight subjects achieved the criterion standard (2.2 miles for females and 2.4 miles for males), while 47 subjects did not achieve that standard. Triceps and medial calf skinfolds (mm) were also measured for each subject. The relationship between 20MSSJ performance and sum of two-site skinfolds was quadratic (F1,72 = 4.4, p < .05). The equation for predicting 20MSSJ performance (miles) from sum of two-site skinfolds (mm) is: 20MSSJ = 3.667 - 0.087(sum) + 0.001(sum)2 (R = .64, SEE = 0.41 miles). 20MSSJ performances were adjusted for sum of two-site skinfolds by adding the mean 20MSSJ value to the residual for estimating 20MSSJ from sum of two-site skinfolds for each subject. After 20MSSJ performances had been adjusted for sum of two-site skinfolds, 27 subjects achieved the 20MSSJ criterion standard, while 48 subjects did not achieve that standard. There was only 72 percent agreement between the unadjusted and adjusted classifications (χ2 = 11.8, p < .05). These data suggest that the relationship between 20MSSJ performance and sum of two-site skinfolds is strong enough to justify the adjustment of 20MSSJ performances for sum of two-site skinfolds. 20MSSJ performances adjusted for sum of two-site skinfolds may be more appropriate for evaluating cardiorespiratory fitness independent of body composition than unadjusted 20MSSJ performances in adolescents.

Subcutaneous adiposity and relative fat patterning in adult white and migrant asian males in Britain

A comparative study of subcutaneous adiposity and relative fat patterning in adult White (n=262) and migrant Indian (n=39) and Pakistani (n=100) males living in Peterborough, Cambridgeshire revealed no significant difference in the level of generalised adiposity (measured as body mass index) between the ethnic groups. However, Asians had significantly higher means for all five truncal skinfolds; for all upper body: upper extremity, upper body: lower extremity, central body: upper extremity and central body: lower extremity skinfold rations; more total subcutaneous adiposity; and significantly more subcutaneous fat in subscapular, suprailiac and abdomen regions relative to total subcutaneous fat. However, Asian men had significantly less subcutaneous fat in all the extremity sites relative to total subcutaneous adiposity and lower mean forearm subcutaneous adiposity. Discriminant analysis revealed that 80.6% of all individuals were correctly classfied, with Whites being grouped more correctly than Asians. Suprailiac/forearm and suprailiac/triceps skinfold ratios, height, weight, age, body mass index, and subscapular, midauxillary, chest and medial calf skinfolds were among the most important discriminating variables/ratios of the three ethnic groups.

Comparisons of fatness indicators in Budapest children

The aim of this study was to estimate the fatness level of Budapest children and youth in different ways and to compare these estimations using a large representative sample. Eighteen body measurements were taken on 2606 healthy boys and 2471 healthy girls aged between 3 and 18 years. About 20% of this sample was measured by the Futrex 5000A near infrared (NIR) spectrophotometer to assess the body fat percent (data of 419 boys and 462 girls aged between 5 and 18 years were analysed). Triceps skinfold thickness (TSF), sum of triceps, medial calf, subscapular and suprailiac skinfold thicknesses (SFS), body fat percent estimated according to Slaughter et al. (%BF), BMI (calculated from height and weight) and body fat percent assessed by NIR-method (NIR%BF) were compared. chi 2 tests of independence show significant connections among the distributions ranged by the five fatness indicators. However, correlation coefficients and standard errors indicate that strong relationships are only among the assessments based on skinfold thicknesses (r = 0.92-0.97, SEE = 1.8-2.6%). BMI and NIR%BF assess body fatness differently compared to skinfold thicknesses: r-values are moderate and SEE-values are relatively large (r = 0.59-0.87, SEE = 1.9-4.7%). These findings can be seen in both the boys and the girls. NIR%BF comparing to %BF significantly overpredicts body fat percent in the boys and significantly underpredicts it in the girls. BMI, height and weight are not in significant correlation with NIR%BF in the boys but there are moderate correlations in the girls. Our suggestion is that more research is needed with the use of NIR-method in children and adolescents, and it is necessary to refine prediction equations taking into consideration very carefully sex sand age differences.

COMPARISON OF CIRCUMFERENCE-BASED AND SKINFOLD-BASED BODY FAT ESTIMATION EQUATIONS

1572 The purpose of this study was to compare body fat estimation equations based on circumference measurements (CIRC) with equations based on skinfold measurements (SF). Both were then compared with equations that combined circumferences and skinfolds (COM). Equations were developed on data from 320 Navy personnel (161 males; 159 females) and cross-validated on data from 60 males and 54 females. Equations were developed separately for males and females using stepwise linear regression with a four-compartment (fat mass, total body water, bone mineral content, and residual lean mass) body composition model as the criterion. The CIRC equation for males included the log10's of the abdomen (AB) and forearm (FA) circumferences. The log10sum of the mid-axillary (MA), medial calf (MC), and supraspinale skinfolds comprised the SF equation. The COM equation contained the log10's of the AB and FA circumferences and the log10 sum of the MA, MC, and iliac crest (IC) skinfolds. R values were 0.921, 0.885, and 0.940 for the CIRC, SF, and COM equations, respectively. Cross-validation R values were 0.865, 0.871, and 0.892. For the females, the CIRC equation included the log10's of the AB, thigh (TH), and shoulder (SH) circumferences. The SF equation included the log10 sum of the triceps, IC, TH, subscapular(SC), AB, MA, and MC skinfolds. The COM equation included the log10 sum of the TH, IC, SC, and MC skinfolds, and the log10's of the AB, SH, and hip circumferences. R values were 0.884, 0.882, and 0.927 for CIRC, SF, and COM, respectively. Cross-validation R values were 0.887, 0.914, and 0.937. Statistical comparisons of R values revealed no significant differences between R values for CIRC and SF equations or between CIRC and COM equations for males. The R for COM was significantly higher than that for SF (p = 0.008). For females, there were no significant differences between CIRC and SF R values, but the R value for COM was significantly higher than both CIRC (p = 0.04) and SF (p = 0.03) R values. In conclusion, the best equation for males or females included both circumferences and skinfolds. However, the equations based on circumferences were as good as the skinfold equations at estimating body fat using a four-compartment body composition criterion.

DNA Polymorphisms in the α2‐ and β2 Adrenoceptor Genes and Regional Fat Distribution in Humans: Association and Linkage Studies

The aim of this study was to investigate the relationships between DNA restriction fragment length polymorphisms (RFLP) in the alpha 2- and beta 2-adrenoceptor genes and body fat distribution in humans. Skinfold thickness measurements and genetic analyses (Southern blot) were performed on 280 individuals (142 parents and 138 offsprings) from the Québec Family Study. Using the association study design in unrelated adults, women but not men carrying the 6.3-kb allele of an alpha 2A-adrenoceptor/DraI RFLP had a significantly higher trunk to extremity skinfold ratio (= sum of subscapular+suprailiac+abdominal skinfolds/sum of biceps+triceps+medial calf skinfolds) compared to women without the allele (1.44 +/- 0.52 vs. 1.12 +/- 0.33; p < 0.005 after adjustment for age, p < 0.002 after adjustment for age and body mass index or for age and subcutaneous fat). Using the sib-pair linkage procedure, a significant inverse relationship was found between the proportion of alleles identical by descent shared by sibs at the alpha 2A RFLP marker locus and the squared differences of the trunk to extremity skinfold ratio (p = 0.02 after adjustment for age or for age and body mass index or for age and subcutaneous fat). For a beta 2-adrenoceptor/BanI RFLP, no significant association or linkage was found between fat distribution indicators and the marker. These results suggest that alpha 2A-adrenoceptor gene variability detected with DraI is associated with a relative subcutaneous fat pattern favoring accumulation of truncal-abdominal fat in women, and that the alpha 2A-adrenoceptor gene, or a locus in close proximity, may be linked to body fat distribution in humans independently of the overall level of fatness.

Validity of conventional anthropometric techniques for predicting body composition in healthy Chinese adults.

There is little information on the application of generalized prediction equations to ethnic groups other than Europeans and groups of European descent. The purpose of this study was to crossvalidate conventional equations on a group of 56 Chinese adults. Body density was assessed by underwater weighing and also predicted by equations which use a combination of selected skinfolds-biceps, triceps, pectoral, subscapular, abdominal, suprailiac, thigh and calf. There were significant correlations (P < 0.01) between the various methods of predicting percentage fat. However, analysis of variance revealed significant differences (P < 0.01) between mean values. In the men, the Jackson and Pollock equation underestimated, and the Durnin and Womersley equation overestimated, the percentage fat predicted by underwater weighing. The best predictor site in this group was the medial calf skinfold (r = 0.81), which is not included in either equation. In the women, the best predictor sites were the triceps, suprailiac and thigh. As these sites are also used in the Jackson et al. equation, it is not surprising that there was no difference between the prediction of percentage fat by this equation and underwent weight. It is concluded that the Durnin and Womersley and Jackson and Pollock equations tend to overestimate and underestimate, respectively, the percentage fat in Chinese men. Alternative equations which use the calf skinfold may be more appropriate for this ethnic group. In Chinese women, there appears to be good agreement between Jackson and Pollock and hydrodensitometric estimations of percentage fat.

Relative fat distribution: Relationship to skeletal maturation, growth status, and motor fitness of boys 8-11 years of age.

Skeletal maturia (Tanner-Whitehouse II [TW II]), growth status, and motor fitness were compared in boys having high and low trunk/extremity skinfold ratios (T/E ratio). The T/E ratio was based on the sums of the subscapular and midaxillary, and the triceps and medial calf skinfolds. The sample included 80 boys, age 8 through 11 years, who represented the highest and lowest quartiles of the distribution of the T/E ratio (10 boys per quartile in each age group). Chronological and skeletal ages did not differ between boys in the highest and lowest quartiles, with the exception of the 10-year-old sample in the highest quartile, in whom skeletal age was significantly advanced. Boys in the highest quartile tended to be slightly taller, but especially heavier and fatter (sum of four skinfolds). They thus had a higher body mass index (BMI), which was elevated in part due to increased muscle mass as reflected in a larger estimated midarm muscle circumference. In contrast, boys in the lowest quartile tended to perform better, both absolutely and per unit body mass, in the three motor tests (run, jump, throw), while there were no consistent differences in absolute strength. However, boys in the lowest quartile tended to be stronger and to perform better per unit body mass. The results thus suggest that more centrally distributed subcutaneous fat may have a negative effect on the motor fitness of children, and this effect is mediated in part through excess fatness. © 1994 Wiley-Liss, Inc.

Apolipoprotein polymorphisms and phenotypic variability in American Samoans: Preliminary data.

Human apolipoprotein genetic variation is associated with phenotypic variability in body habitus and in lipid and glucose metabolism, interrelated aspects of human physiology. In this study, structural variation at the apolipoprotein E and H loci, documented for 67 residents of American Samoa, was investigated for associations with body habitus, plasma glucose, glycated hemoglobin, pulse rate, and blood pressure. Compared to men with the common APO E*3 allele, those with APO E*2 had higher weight, percent trunk fat, ratio of subscapular to triceps skinfold, and larger subscapular, suprailiac, and medial calf skinfolds; men with the APO E*4 allele had lower weight, body mass index (BMI), upper arm circumference, estimated arm muscle circumference, and a smaller suprailiac skinfold. Such variability by apolipoprotein E types was not observed in Samoan women nor when men and women were combined for analysis with or without statistical control for sex. At the APO H locus, little difference in aspects of body habitus was observed between men carrying the most common APO H*2 allele and the less common APO H*1 allele. Percent trunk fat and the subscapular to triceps skinfold ratio tended to be larger in women with the APO H*1 allele. Plasma glucose and glycated hemoglobin were lower in Samoans with the APO E*2 and E*4 alleles, but higher in those with the APO H*1 allele. Blood pressure and pulse rate were lower and higher, respectively, in those with the APO E*4 allele. The observed associations differ from those observed in Caucasian, Japanese, and Hispanic samples, and support suggestions that associations between apolipoprotein polymorphisms and morphological measures vary across ethnic groups. © 1993 Wiley-Liss, Inc.

An evaluation of the associations between socioeconomic status and the growth of Mexican-American children: data from the Hispanic Health and Nutrition Examination Survey (HHANES 1982–1984)

This study considers the associations between 1) various measures of growth (triceps, subscapular, medial calf, and suprailiac skinfold thickness; stature; weight; and weight/stature2) and 2) poverty status in a sample of 3587 Mexican-American children from HHANES (1982-1984). Comparisons are made with data for white children and black children in NHANES II (1976-1980). Differences between poor (at or below the poverty line) and nonpoor (above the poverty line) Mexican-American children were small and not statistically significant for most of the variables that were compared. Poor adolescent Mexican-American girls, however, had significantly greater mean skinfold thicknesses than nonpoor Mexican-American girls. When poverty status was held constant, Mexican-American children tended to be shorter but heavier and fatter than white children and black children. Across poverty status groups, weight/stature2 tended to be relatively high in Mexican-American children.

Body fat distribution and non-insulin dependent diabetes mellitus in North American Indians

This study was an investigation of fat patterns in diabetics (n=22) and non-diabetics (n=22) to determine if abdominal obesity was associated with non-insulin dependent diabetes mellitus (NIDDM) in Native Canadians with a high prevalence of NIDDM. All subjects were aged 35 years and over. Non-diabetics were pair-matched to diabetics on age (within 5 years), sex and band. The following anthropometric measurements were made on all participants: weight, height; waist and hip circumferences; subscapular, triceps, midaxillary, suprailiac, lateral forearm, umbilical, rear calf, medial calf, front thigh and rear thigh skinfolds. Among males, diabetics had larger values for both waist and hip circumferences; midaxillary, subscapular, umbilical, and medial calf skinfolds; body mass index (kg/m 2); and sum of triceps, subscapular and midaxillary skinfolds. Non-diabetic women had larger mean values for rear calf and medial calf skinfolds compared to diabetics. These findings suggest that abdominal obesity is associated with NIDDM in men. Among women, we find weak support for this association. The high prevalence of obesity in this population may reduce the ability to distinguish between diabetics and non-diabetics on the basis of the above anthropometric measures.

Relative body fat and anthropometric prediction of body density of male athletes.

Two hundred and seven male members of South Australian representative squads in 18 sports (mean +/- s = 24.2 +/- 4.7 years) were tested in order to provide descriptive data on relative body fat (% BF), develop a population specific equation and cross-validate existing equations. Measurements were taken of 10 circumferences, 2 diameters and 8 skinfolds; body density (BD) was measured by underwater weighing with the residual volume (RV) being determined by He dilution. The overall mean BD was 1.0761 g X cm-3 (s = 0.0085 g X cm-3; range = 1.0465-1.0968 g X cm-3) which corresponded to 10.0% BF according to Siri (s = 3.7%; range = 1.3-23.0%). The games players (n = 129) registered an overall mean of 10.3% BF (s = 3.7%; range = 2.2-23.0%). There were significant differences (p less than 0.05) for % BF between the lacrosse players (mean = 12.3%) an both the Australian Rules footballers (mean = 8.0%) and track and field athletes (mean = 8.7%). A stepwise multiple regression on 185 subjects yielded the following equation, which had an R of 0.787: BD = 1.078865-0.000419 (sigma abdominal, medial calf, front thigh and juxta-nipple skinfolds in mm) +0.000948 (neck circumference in cm) -0.000266 (age in decimal years) -0.000564 (ankle circumference in cm). Only those predictors which resulted in a significantly increased correlation (p less than or equal to 0.05) were included. The standard error of estimate of 0.00537 g X cm-3 was equivalent to 2.3% BF at the mean. This equation was satisfactorily cross-validated against the BD of a separate sample (n = 22) from the same population. However, cross-validation of 11 previously published equations indicated that they have limited applicability to State representative sportsmen.

Familial resemblance in fatness indicators.

Family resemblance in fatness has been studied in 481 individuals from 114 families of French descent living in the greater Quebec city area. Subjects were measured for the following fatness indicators: triceps, biceps, subscapular, suprailiac, abdominal and medial calf skinfolds. The sum of these six skinfolds as well as a prediction of percent body fat (Durnin and Rahaman 1967) were also considered. Data were standardized for appropriate age and sex classes yielding SS scores. The influence of relevant lifestyle variables (energy intake, energy expenditure and socioeconomic status) were statistically removed from SS yeilding residual scores (RS) that were then submitted to familial analyses. Analyses of variance indicate that there is a larger between family variation than within (P less than or equal to 0.01) for SS when considering either the whole nuclear family or sibships; in these instances, the intra-class correlation ranges from 0.15 to 0.26. There was, however, no significant resemblance among spouses for the SS fatness indicators. Similar values were essentially found for RS fatness indicators. Furthermore, husband-wife inter-class correlations were not significant with the exception of subscapular and calf skinfold RS. Covariations between biological relatives are however significant (0.16 less than or equal to r less than or equal to 0.24, P less than or equal to 0.01) for SS and remain essentially unchanged after statistical control over the lifestyle variables (0.16 less than or equal to r less than or equal to 0.40, P less than or equal to 0.01). The findings that spouses do not covary significantly in fatness, while biological relatives of traditional nuclear families exhibit a significant degree of resemblance even after statistical control over daily energy intake, daily energy expenditure and socioeconomic status provide evidence supporting the hypothesis that there is a substantial genetic effect in human fatness.