Estudo longitudinal do crescimento corporal de escolares de 10 a 14 anos: dimorfismo sexual e pico de velocidade

Abstract

O acompanhamento do crescimento corporal durante a adolescência é um importante indicador de saúde, além de possibilitar a identifi cação do estado maturacional dos indivíduos. Frente a isso, os objetivos do estudo foram: a) descrever o desenvolvimento da estatura e de massa corporal de meninas e meninos dos 10 aos 14 anos de idade e suas diferenças nesse processo, e; b) identifi car o momento e a magnitude do pico de velocidade em altura (PVA) e do pico de velocidade em massa corporal (PVP) de meninos e meninas. Para tanto, foram acompanhados dos 10 aos 14 anos de idade, 70 escolares dos dois sexos. Foram medidas a estatura (cm) e a massa corporal (kg) dos mesmos indivíduos, anualmente, de 2001 a 2005. Os resultados demonstram que até os 12 anos não existem diferenças consistentes entre os sexos, e que aos 13 e 14 anos, os meninos são maiores e mais pesados que as meninas. O PVA e PVP ocorreram no mesmo período, sendo nos meninos dos 12 para os 13 anos, e nas meninas dos 10 para os 11 anos. Frente aos resultados, concluímos que, até o PVA dos meninos, não existem diferenças expressivas no crescimento corporal entre os sexos e que, a partir desse evento, os meninos fi cam maiores e mais pesados que as meninas. Além disso, concluímos que o PVA e o PVP ocorrem cerca de dois anos antes nas meninas. palavras-chave: Dimorfi smo sexual; Crescimento físico; Pico de velocidade. aBstraCtMonitoring physical growth during adolescence provides an important indicator of health status and also makes it possible to identify individuals' maturity stages. The objectives of this study were to: a) describe the progression of the heights and the body mass of girls and boys from 10 to 14 years of age and the differences between the sexes, and; b) to identify the point and magnitude of peak height growth velocity (PHV) and peak body mass velocity (PMV) for boys and girls. In order to achieve these objectives 70 schoolchildren of both sexes were followed from 10 to 14 years of age. Their height (cm) and body mass (kg) were measured annually from 2001 to 2005. The results demonstrate that up until 12 years of age there are no consistent differences between the sexes, but that at 13 and 14 years of age the boys are taller and heavier than the girls. The PHV and PMV both occurred during the same periods, being from 12 to 13 for boys and from 10 to 11 for the girls. Based on these results we concluded that until the boys reach their PHV, there is no signifi cant difference in physical growth between the sexes and that after this point the boys become taller and heavier than the girls. Furthermore, we concluded that girls reach PHV and PMV around 2 years before the boys. key words: Sexual dimorphism; Physical growth; Peak of velocity.

Crescimento físico e estado nutricional de escolares: estudo comparativo (1997 e 2009). DOI: 10.5007/1980-0037.2011v13n3p216

“…These findings suggest harmonious growth since increases in height were accompanied by body weight gains. Similar results have been reported in other studies 14,18,24,25,28,29 . With respect to BMI adequacy, significant differences were observed between the 1997 and 2009 samples, with the observation of an increase in the frequency of obese individuals.…”

“…Although the present study was not a longitudinal investigation, a tendency towards a linear increase of height with age was observed, in agreement with other studies 18,25 . Like height, body weight also tended to increase linearly with age despite the greater variability (unstable) of this variable.…”

“…). Another aspect is that the growth spurt may also be anticipated in boys as suggested by other studies 18 . There were no significant differences in the body weight of boys or girls between 1997 and 2009.…”

“…, who evaluated the physical growth of male and female schoolchildren from the city of Florianópolis and observed significant differences in height in favor of girls at ages 11 and 12. This anticipation might be explained by factors related to the phenomenon of biopsychosocial stimulation, as well as by increased living standards, improved health conditions, and access to better quality food 2,10,18 . Lower crude heights than those reported by Pires and Lopes 14 were obtained in the present study for girls and boys at all ages and in the two years of data collection.…”

“…In this respect, many studies have been conducted in Brazil to identify and monitor the behavior of these variables [11][12][13][14][15][16][17][18][19][20][21][22][23] , especially in the State of Santa Catarina 13,15 . In 1997, Machado and Krebs 12 investigated the physical growth profile and nutritional status of schoolchildren aged 10 to 14 years from the Island of Santa Catarina and observed significant rates of overweight and obesity.…”