RESUMEN
We aimed to investigate whether the expression levels and polymorphisms in the ADRB2 gene have influenced the anthropometric and cardiometabolic outcomes changes in obese/overweight children submitted to physical exercise programs. This longitudinal study included 197 overweight or obese children aged 10-16 years, submitted to physical exercise programs - three sessions per week for 12 weeks. Anthropometric and cardiometabolic profile was collected before and after interventions. The ADRB2 gene expression levels were also measured in these two moments in a small intervention group (n = 17) and a control group (n = 18). Arg16Gly and Gln27Glu polymorphisms were genotyped. A positive correlation between ADRB2 expression and loss of body fat (%) (p = 0.038) was observed, which remained after sex and BMI change corrections. Carriers of the Glu27Glu genotype presented a better response to physical exercise programs regarding their triglycerides levels and triglyceride-glucose index (p = 0.001 for both). The participants' responsiveness to physical exercise programs showed variation due to the ADRB2 gene expression and the Gln27Glu polymorphism. A more significant loss of body fat was associated with higher levels of ADRB2 expression, and the Glu27Glu genotype was associated with a better cardiometabolic response. The Arg16Gly polymorphism did not show interaction with the responsiveness to physical exercise.