ß2 adrenergic interaction and cardiac autonomic function: effects of aerobic training in overweight/obese individuals.

PURPOSE: To verify the influence of different volumes and intensities of aerobic exercise on cardiac autonomic function (CAF) through heart rate variability (HRV) analysis as well the influence of ß2 adrenergic receptor (ADRB2) variants in overweight/obese individuals. METHODS: 70 physically inactive adults were randomly allocated into the following 16-week training: 1-high-intensity interval training (HIIT) (n = 25, 1 × 4 min bout at 85-95%HR peak, 3×/week), 4-HIIT (n = 26, 4 × 4 min bouts at 85-95%HR peak, interspersed with 3 min of recovery at 50-70%HR peak, 3×/week), and moderate continuous training (MCT) (n = 19, 30 min at 60-70%HR peak, 5×/week). Before and after the exercise training, anthropometric, BP, cardiorespiratory fitness, and HRV measures were evaluated. R-R intervals recorded for 10 min in a supine position at pre- and post-intervention were used to analyze HRV in the plot-Poincare indexes (SD1, SD2), and frequency-domain (LF, HF, LF/HF). Full blood samples were used for genotyping. RESULTS: 4-HIIT and MCT showed positive outcomes for almost all variables while 1-HIIT had a positive influence only on SBP and SD2 index. No associations were observed between isolated ADRB2 variants and changes in HRV. In the analysis of the interaction genotypes, all groups responded positively for the SD1 index of HRV and only the H1 (GG and CC) and H2 (GG and CG + GG) groups presented increases in the RMSSD index. Furthermore, there was an increase in the LF index only in the H3 (CC and AA + AG) and H4 (AA + AG and CG + GG) groups. CONCLUSIONS: ADRB2 variants and aerobic exercise training are important interacting variables to improve autonomic function and other health variables outcomes in overweight or obese individuals.

Multicomponent Training Changes Blood Pressure and Redox Status in Older Women: Influence of ß2 Adrenergic Receptor Haplotypes.

The ß2 adrenergic receptor (ß2-AR) plays an important role in vascular smooth muscle. However, the interaction between Arg16Gly and Gln27Glu ß2-AR polymorphisms, and exercise training has not yet been established. This study evaluated the influence of these ß2-AR polymorphisms on body composition, aerobic capacity, blood pressure, lipid profile, nitric oxide, and redox status at baseline and in response to an exercise program in women aged 50-79 years. Genotype and haplotypes were analyzed in association with the previously mentioned variables before and after the multicomponent training (12 weeks, 2 sessions/week, 90 min/session, and exercise intensity between 13 and 15 on the Borg scale). Individuals who carry ß2-AR Arg16Arg/Gln27Gln genotypes presented more improvements in blood pressure, body composition, aerobic capacity, and redox status in response to a multicomponent training program compared with individuals who do not carry this haplotype. In some years, the genetic profile may be used to predict which exercise program can induce more health benefits for each person.

Effect of Multicomponent Training on Blood Pressure, Nitric Oxide, Redox Status, and Physical Fitness in Older Adult Women: Influence of Endothelial Nitric Oxide Synthase (NOS3) Haplotypes.

The purpose of this study was to verify the influence of the genotype or haplotype (interaction) of the NOS3 polymorphisms [-786T>C, 894G>T (Glu298Asp), and intron 4b/a] on the response to multicomponent training (various capacities and motor skills) on blood pressure (BP), nitrite concentration, redox status, and physical fitness in older adult women. The sample consisted of 52 participants, who underwent body mass index and BP assessments. Physical fitness was evaluated by six-minute walk, elbow flexion, and sit and stand up tests. Plasma/blood samples were used to evaluate redox status, nitrite concentration, and genotyping. Associations were observed between isolated polymorphisms and the response of decreased systolic and diastolic BP and increased nitrite concentration and antioxidant activity. In the haplotype analysis, the group composed of ancestral alleles (H1) was the only one to present improvement in all variables studied (decrease in systolic and diastolic BP, improvement in nitrite concentration, redox status, and physical fitness), while the group composed of variant alleles (H8) only demonstrated improvement in some variables of redox status and physical fitness. These findings suggest that NOS3 polymorphisms and physical training are important interacting variables to consider in evaluating redox status, nitric oxide availability and production, and BP control.