Estudo do limiar anaeróbico ventilatório em adolescentes com peso normal e excesso de peso

• Ano de defesa: 2012
• Autor(a) principal: Gomes, Kamilla Bolonha
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal do Espírito Santo; BR; Mestrado em Educação Física; Centro de Educação Física e Desportos; UFES; Programa de Pós-Graduação em Educação Física
• Palavras-chave em Português: Anaerobic threshold; Adolescent; Obesity; Physical fitness; Limiar anaeróbio; Adolescentes; Obesidade; Aptidão física; Educação Física; 796
• Link de acesso: http://repositorio.ufes.br/handle/10/6102

The aim of this study was to identify and compare the values of cardiorespiratory variables at ventilatory anaerobic threshold (VAT) of adolescents of both genders with normal weight, overweight and obesity. The participants were 311 adolescents aged among 10 and 14 years (163 girls and 148 boys), students in the municipality of Vitória/ES. We measured body weight and height to calculate body mass index (BMI). From the classification by BMI, the criteria of the World Health Organization (2007), adolescents were divided into groups: normal weight (NWG), overweight (OWG) and obesity (OG). They underwent a resting electrocardiogram, and then performed the cardiopulmonary exercise test on a treadmill (Inbrasport Super ATL) using ergospirometer MedGraphics Corporation (MGC) and performing the ramp protocol, consisting in a progressive increase speed and incline of the treadmill. The VAT was identified by the V-slope method and/or the ventilatory equivalent of oxygen (VE/VO 2). To assess cardiorespiratory fitness in VAT the following variables were analyzed: oxygen consumption (VO2 L.min -1 and ml.kg -1 .min -1 ), carbon dioxide production (VCO2 L.min -1 ), respiratory exchange ratio (RER), minute ventilation (VE L.min -1 ), heart rate (HR beats.min -1 ), VE/VO 2, ventilatory equivalent for carbon dioxide (VE/VCO2), percentage of maximal O 2 (%VO2max VAT ) and maximal HR (%HR max VAT ) and speed (km/h). Statistical analysis was performed one-way ANOVA for comparisons of cardiorespiratory variables and the variable related to the workload between the three BMI classifications and classifications of BMI in each gender; Student's t test for comparisons between genders considering p < 0.05 for statistical significance. The main results were: VO2 VAT (ml.kg -1 .min -1 ) was higher for NWG compared to OWG and OG (20.0 ±7.3; 16.5 ±5.9 and 13, 6 ±3.2, respectively), there was no statistical difference between OWG and OG for VO2 VAT (ml.kg -1 .min -1 ), there was no statistical difference between groups for FC VAT , HRmax, %HRmax, RTRVAT and VelVAT ; when comparing gender, the boys had the highest averages for NWG VO2 VAT (L.min -1 and ml.kg -1 .min -1 ), VCO 2 VAT (L.min -1 ), RTR VAT, VE VAT (L.min -1 ) and speed (km/h) than girls the same group, there was no statistical difference between genders in OWG, except for VO2max (higher in boys than in girls), and OG, except for %HRmax VAT (higher in girls than in boys). It can be concluded from this study that overweight adolescents had impaired cardiorespiratory fitness (submaximal level) compared to normal weight adolescents. The overweight adolescents are similar to obese, cardiorespiratory responses in terms of the VAT, showing that the former present a cardiorespiratory fitness as low as the last. Boys and girls with overweight showed no differences in cardiorespiratory responses in LAV, signaling the reduction of gender differences in this age group, usually found in adolescents with normal weight due to the process of growth and maturational status.