ALLOMETRIC SCALING OF PHYSICAL PERFORMANCE IN CHILDREN AND YOUTH FROM MAPUTO, MOZAMBIQUE

Abstract

1597 The purpose of this study was to analyse the power of allometric scaling in the interpretation of physical performance in children and youth from Mozambique. Sample size comprises 317 girls and 276 boys between the ages of 8 to 15 from the capital city, Maputo. Height, weight, sit-up's (number in 60s), hand grip, agility run, and one mile run were recorded. The analysis was done according to the well-known power function formulae: Y=aXb, where Y is the performance variable, X is height or weight, a is a constant multiplier, and b is the empirical dimensional exponent. Empirical b values were compared to theoretical expectations. All analysis were done in SYSTAT 7.0. For hand grip the exponents were greater than expected (boys: height3.84; weight1.17; girls: height3.86; weight1.21); in agility run the b values were not significantly different from zero; empirical b values for the mile run (boy: height1.46; girls: height1.88) and sit-up's (boys: height2.08; girls: height1.20). Weight exponents for sit-up and mile run were not significantly different from zero. In conclusion we have to point out the importance of considering the fact that physical performance is affected by differences in size and that scaling is a procedure to adjust for such differences in children and youth of both gender. Major findings suggest that: (1) empirical b values were greater than theoretical expectations; (2) physical performance increased more rapidly than did body size; (3) exception was made for agility run, and probably some weight independent performance (sit-up and mile run) due to the absence of excess weight and body fat in boys and girls; (4) the effect of size changes in physical performance is somehow dependent of gender; (5) and it is open to debate the idea of a constant shape as growth occurs, since in this study the b value relating weight to height was 2.89.