Cardiac Autonomic Modulation at Rest and Aerobic Fitness in Overweight Young: 3374 Board #135 May 30, 8

The overweight is associated the cardiometabolic diseases. Thus, the evaluation of cardiac autonomic modulation at rest and of the aerobic fitness by heart rate variability (HRV) is an useful tool to evaluation of autonomic function in different populations. PURPOSE: To determine the association between cardiac autonomic modulation at rest and aerobic fitness in overweight young, apparently healthy. METODOLOGY: Eleven sedentary overweight men (BMI: 30.25 ± 3.55 kg.m-2, waist circumference - WC: 97.00 ± 6.72 cm) with 21.24 ± 1.69 years old were evaluated. The heart rate (HR) and HRV were measured in a sitting position after 10 min rest, measured in the last 5 min (heart rate monitor). The HRV index (RR interval, treated in Kubios HRV program) used were those obtained in the time domain: standard deviation of RR intervals instantaneous (SD1); standard deviation of RR intervals analyzed long-term (SD2); root square of mean of squared successive differences between adjacent RR (RMSSD); percentage of differences between successive RR intervals that are < 50 ms (pNN50). Aerobic fitness was assessed by HRV threshold (HRVT), in a progressive maximal test in cycle ergometer, with increments of 15W/min, so the HRVT was considered the first exercise intensity with SD1 equal or less than 3 ms (Lima, 1999). Descriptive statistics, Pearson correlation coefficients (*) and Spearman’s Rank (**) p <0.05 was used. RESULTS: The BW (94.55 ± 11.07 kg) was significantly correlated (r) with WC: 0.91*; HR: 0.62*; SD1: - 0.67*; SD2: - 0.66* and RMSSD: - 0.67*. The HR (78.39 ± 12.97 bpm) was significantly correlated with WC: 0.73*; SD1: - 0.73*; SD2: - 0.84*; RMSSD: - 0.73*, pNN50: - 0.62** and HRVT: - 0.63*. The HRVT (71.67 ± 42.94 W) was significantly correlated with SD1: 0.64*; SD2: 0.72*; RMSSD: 0.64* and pNN50: 0.91** CONCLUSION: The data indicate that the BW was associated inversely with cardiac autonomic modulation index at rest, and these were associated with aerobic fitness. With this, the reduction of BW and improved aerobic fitness by regular physical exercise can promote improvements in cardiac autonomic modulation both at rest and during exercise, preventing future cardiovascular complications in overweight youth. Supported by FAPEMAT (Process 151411/2014), CNPq