The main objective of this thesis was to analyze the effect of exercise training on the maximal fat oxidation (FATMAX) and the cardiometabolic profile in overweight adolescents, as well as investigating the influence of polymorphisms genes in the ADRB2 and ADRB3 genes. For this, three different studies were conducted, in Study 1, the objective was to compare the influence of two protocols of exercise training on maximal fat oxidation and profile cardiometabolic in overweight adolescents. In Study 2, the same variables as in the first study, plus analysis of possible interactions genetics with the Gln27Glu polymorphism of the ADRB2 gene and in Study 3 with the Trp64Arg of the ADRB3 gene. The total sample consisted of 203 overweight adolescents, of both sexes, aged between 10 and 17 years. The evaluations were carried out in the phase initial and after 12 weeks of intervention programs. the adolescents were submitted to clinical analyses, which measured height, body mass, circumference abdominal (CA), pubertal stage, systolic (SBP) and diastolic (DBP) blood pressure. Body mass index (BMI) and BMI-score Z were calculated. basal insulin concentrations (INS), basal blood glucose (GLI), total cholesterol (TC), high density lipoprotein (HDL-c), low density lipoprotein (LDL-c), lipids total (LT) and triglycerides (TG). Body composition was obtained by bioelectrical impedance (BIA). Physical fitness tests consisted of cardiorespiratory assessment performed by incremental treadmill test and by the maximum strength test (1RM). From the maximum direct oxygen consumption value (VO2max) there was a cardiorespiratory profile classification and FATMAX calculation. in the second and third studies were added to genetic evaluations, in which the genotyping of polymorphisms were performed by the Taqman PCR method. The sample was stratified in two intervention groups with different protocols and a control group without exercise (GControl). The continuous aerobic training group (GTAContinuo) was composed of sessions 90 min of aerobic exercise (45 min of indoor cycling and 45 min of walking) plus 20 min of stretching, totaling 110 minutes. The combined training group (GTCombined) consisted of 10 minutes of warm-up, 6 resistance exercises (3 series; 6-10 rep; 30 minutes), followed by 30 minutes of aerobic exercise (walk/run), totaling 70 min/session. The weekly frequency of groups intervention was three times, for a period of 12 weeks, while the intensity of the aerobic exercises of the protocols was progressive from 35 to 85% of the VO2max or HRR Student's t test or the U - Mann Whitney test was used to compare the adolescents according to sex and analysis of variance (ANOVA) to assess the effects of time and the group x time interaction. For the main variables that had an effect significant in the training group after 12 weeks the paired t test was performed and the Cohen’s d. The significance level adopted was p≤0.05. Results Study 1: by dividing the sample according to sex, boys had greater height (p<0.01), FFM (p<0.01), %MLG (p<0.01), QUICKI (p<0.01), absolute VO2max (p<0.01) and FATMAX (p<0.01), while girls had higher WHtR (p<0.01), %MG (p<0.01) and TG (p=0.04). After 12 weeks, among girls, the interaction factor group x time indicated that GTAContinuous greater reduction in BM (p<0.01), BMI (p<0.01), BMI-z (p<0.01), and, increase in HDL-c (p<0.01), absolute VO2max (p<0.02), VO2max relative to MLG (p<0.01) and FATMAX (p<0.04). In addition, in GTCombinado there was a greater reduction in MG (p<0.01) and %MG (p<0.01), and more significant increase in FFM (p<0.01) and QUICKI (p<0.01). Between the boys, there was a greater reduction in BM (p=0.01), BMI (p=0.01), BMI-z in the GTAContinuos (p=0.01), CA (p=0.01) and RCEst (p=0.01), as well as an increase in FATMAX (p=0.01), while in GTCombinado there was a greater reduction in MG (p=0.01), %MG (p=0.03) and HOMA-IR (p=0.01), and, more than QUICKI increase (p=0.01). Finally, in GControle there was increase in DBP (p=0.01). Conclusion Study 1: both intervention protocols resulted in improvements in health parameters among adolescents, however the TAContinuo was more efficient in increasing the maximal fat oxidation and the TCombined provided a more effective decrease in fat mass and increased insulin sensitivity in overweight adolescents of both sexes. Results Study 2: the frequency of the 27Glu allele was 24.68% (p=0.13). the bearers of the 27Gln allele showed lower means of RCEst (p=0.03) and TC (p=0.03), as well as higher FATMAX rates (p=0.02) when compared to carriers of the 27Glu allele. After 12 weeks, carriers of the 27Gln allele of GTAContinuo OBTAINED greater reduction of MC (p<0.01), BMI (p<0.01), BMI-z (p<0.01), CA (p<0.01) and RCEst (p<0.01), in addition to increase in HDL-c (p<0.01) and absolute VO2max (p=0.01). However, allele carriers 27Gln of GTCombinado showed greater reduction of MG (p<0.01), %MG (p<0.01) and FCMAX (p=0.05), as well as an increase in MLG (p=0.05), QUICKI (p<0.01) and VO2max relative to FFM (p<0.01). Among the carriers of the 27Glu allele of GTCombinado, it was observed greater reduction of HOMA-IR (p<0.01) and FATMAX zone (p=0.02), in addition to increase of FATMAX (p<0.01). Finally, an increase in DBP (p=0.01) was identified among allele carriers 27Glu of the GControl. Conclusion Study 2: carriers of the 27Gln allele in GTAContinuous benefited from the reduction of adiposity parameters, in addition to the increase in HDL-c and absolute VO2max and reduction of fat mass and FCMAX, and in GTCombinado they obtained increase in MLG, QUICKI and VO2max relative to MLG. However, among allele carriers 27Glu of GTCombinado showed greater reduction of HOMA-IR and FATMAX zone, in addition to of increase of FATMAX. Finally, an increase in DBP was identified among patients with 27Glu allele of the GControl. Results Study 3: The allelic frequency of 64Arg was 16.46% (p=0.67). Adolescents carrying the polymorphism (64Arg allele) presented higher means TC (p<0.01), LDL-c (p<0.01) and HRREP (p=0.04) compared to noncarriers of the polymorphism (64Trp allele). After 12 weeks, group x interaction was observed time only of the 64Trp allele and the GTAContinuous in the reduction of the BMI-z (p=0.01). The effect time indicated that there were reductions in BMI-z, AC, MG, %MG, in groups GTAContinuo and GCombined, regardless of the presence or absence of the polymorphism. It was also noticed increase in HDL-c, VO2max and FATMAX (GTAContinuous > GTCombinado), as well as decrease in HOMA-IR and increase in QUICKI (GTCombined > GTAContinuous) in both the genotypes. In addition, in GTAContinuo the 64Arg allele carriers presented significant reduction in FCREP (p=0.00) and in GTCombinado the 64Trp allele carriers showed a significant reduction in insulin (p=0.01). Conclusion Study 3: the intervention protocols provided results on cardiometabolic and FATMAX, regardless of the Trp64Arg polymorphism, however there was an interaction between the allele 64Trp and GTAContinuous only for IMC-z. Final Considerations: physical exercise proved to be an essential factor in promoting important biological adaptations with relevant implications for preventing the risk of development or progression of obesity and its related diseases in both sexes. There was interaction between carriers and non-carriers of the Gln27Glu polymorphism in both protocols training, with emphasis on carriers of the 27Glu allele of GTCombinado that showed greater reductions in insulin resistance and increased FATMAX. Regarding to the Trp64Arg polymorphism, both training protocols promoted reductions in body composition, improvement of cardiometabolic parameters and maximal fat oxidation, regardless of the presence or absence of the polymorphism.
Keywords: lipolysis, genetic polymorphism, physical exercise, cardiometabolic profile, adolescents.