Study of growth in rural school children from Buenos Aires, Argentina using upper arm muscle area by height and other anthropometric dimensions of body composition

The primary objective was to compare growth and body composition in an infa ntile rural population by means of the upper arm muscle area by height and other antropometric measurements. Research was carried out by Way of a cros s sectional study, including 80% (321 6-13 year olds) of the schoolchildren living in General Lavalle, a rural community of about 3000 inhabitants. Th e methods and procedures included the evaluation of mother's educational le vels and anthropometric measurements. Height (H), weight, mid upper arm cir cumference, and triceps skinfold (TS) were measured. The body mass index (B MI), the upper arm muscle area (UAMA), the upper arm fat area (UAFA) and th e upper arm muscle area by height (UAMAH) were calculated. Variables were g rouped by gender and age and transformed into z-scores, using the US anthro pometric standards as reference. The results showed that: (1) the mother ed ucational status was, in relation to z-scores, as in an urban population, a nd (2) the z-scores for BMI, UAFA and TS were above the reference, while th e ones for H, UAMA and UAMAH were below the reference. The differences betw een z-scores in relation to mother's educational levels were statistically significant (p < 0.05). UAMA was correlated strongly with H (r = 0.67). The children of General Lavalle tend to be fatty and overweight, while their m uscle mass and H are proportionally low, but with values within the referen ce. Thus, low muscle mass and H are, in general terms, indicative of low pr otein reserves, the systematically low-anthropometry found for UAMAH sugges ts that this index should be used in conjunction with other indexes (e.g. B MI, UAFA) to obtain a more complete asessment of body composition and nutri tional status.