Aerobic Exercise Increases Parasympathetic Activity on BDNF Genetic Variant Val66Met Carriers

Aerobic exercise training (ET) can improve autonomic control, we aimed to investigate the influence of BDNF variant polymorphisms over the sympatho‐vagal balance, pre and post ET in police officers of São Paulo's State Military Police. We hypothesized: 1) presence of the allele Met is associated with a higher rest heart rate (restHR) and lower heart rate variability (HRV), 2) ET will reverse this impairment on the carriers of the Val66Met polymorphism. 80 healthy male (25±4 yrs) underwent to ET on a running track for 5 months. Autonomic control was assessed by the HRV (ECG) at rest. BDNF genotyping resulted in 27.5% (n=22) of Val66Met and 72.5% (n=58) of Val66Val individuals. In the pre ET period, Val66Met presented higher restHR compared with Val66Val (86±13vs.68±6 bpm; p<0.05). HRV was similar between groups. ET similarly improved functional capacity in Val66Met and Val66Val. The pre ET difference on restHR disappeared (67±4 vs. 68±11 bpm; p>0.05). Further analyses showed negative association between restHR changes and oxygen consumption increases (r=‐0.52 e p<0.05). The presence of Met allele could impair parasympathetic modulation of restHR, which is abolished by ET.