Association between knee alignment, body mass index and physical fitness variables among students: a cross-sectional study Associa o entre Alinhamento do Joelho, índice de Massa Corporal e Variáveis de Aptid o Física em Estudantes. Estudo Transversal

OBJECTIVE: To assess the association between malalignment of the knees (genu valgum) and variables of physical fitness among schoolchildren. METHODS: We analyzed data collected between the years 2000 to 2009. The sample comprised 1,141 schoolchildren of both sexes aged 06 to 18 years. To participate in the research, the students must meet the following criteria: age between 6 and 18 years and a full assessment of physical fitness, including measurement of genu valgus in at least one of the semester assessments. Postural evaluation (valgus) was determined by the intermalleolar distance, in centimeter. Body Mass Index (BMI) determined through the growth curves of the World Health Organization. Physical fitness variables (strength of upper and lower limbs, agility, speed and flexibility), were taken according to CELAFISCS standardization. RESULTS: Among male students it was found a prevalence of 23.2% obese, 44.4% overweight and 32.4% eutrophic. Among females, the values were: 30.9% obese, overweight 39.5% and 20.6% eutrophic. When analyzing the prevalence of valgus according to the BMI classifications it was, found a significant positive association in both sexes. Association was found between genu valgum and upper limbs strength only in crude analysis. The other variables, agility, speed and flexibility were not associated even when the analysis was adjusted. CONCLUSION: there was a positive association between malalignment of the knees, body mass index and physical fitness among schoolchildren. OBJETIVO: Verificar associa o entre o mau alinhamento de joelhos (geno valgo) e variáveis de aptid o física em estudantes. MéTODOS: Foram analisados dados coletados entre 2000 a 2009. A amostra foi composta por 1.141 estudantes de ambos os sexos, de 6 a 18 anos. Para participar da pesquisa os estudantes deveriam atender os seguintes critérios: ter entre 6 e 18 anos e uma avalia o completa da aptid o física, incluindo a medida de geno valgo. O valgismo foi determinado pela distancia intermaleolar, com régua em centímetros. Já para a classifica o do índice de Massa Corporal (IMC) usaram-se as curvas de crescimento da Organiza o Mundial da Saúde e as variáveis de aptid o física analisadas (for a de membros inferiores e superiores, agilidade, velocidade e flexibilidade) seguiram a padroniza o CELAFISCS. RESULTADOS: No sexo masculino foi encontra uma prevalência de 23,2% de obesos, 44,4% com excesso de peso e 32,4% eutróficos. Entre o sexo feminino, 30,9% eram obesas, 39,5% com excesso de peso 39,5% e 20,6% eutróficas. Quando analisada a prevalência de valgismo d