Comparison of Polar® RS800G3™ heart rate monitor with Polar® S810i™ and electrocardiogram to obtain the series of RR intervals and analysis of heart rate variability at rest.

The Polar® RS800G3™ rate monitor was released in the market to replace the Polar® S810i™, and few studies have assessed that the RR series obtained by this equipment is reliable for analysis of heart rate variability (HRV). We compared HRV indexes among the devices Polar® RS800G3™, Polar® S810i™ and eletrocardiogram (ECG) to know whether the series of Polar® RS800G3™ are as reliable as those devices already validated. We analysed data from 30 healthy young adults, male, with an average age of 20·66 ± 1·40 years, which had captured the heart rate beat to beat in the three devices simultaneously with spontaneously breathing, first in the supine position and subsequently sit both for 30 min. The obtained series of RR intervals was used to calculate the indexes of HRV in the time domain (SDNN and RMSSD) and in the frequency domain (LF, HF and LF/HF). There were no significant differences in HRV indexes calculated from series obtained by the three devices, regardless of the position analysed, and a high correlation coefficient was observed. The results suggest that the Polar® RS800G3™ is able to capture series of RR intervals for analysis of HRV indexes as reliable as those obtained by ECG and Polar® S810i™.

Efeitos de um programa multidisciplinar sobre a modulação autonômica de crianças e adolescentes com sobrepeso e obesidade / Effects of a multidisciplinary program on autonomic modulation in overweight or obese children and adolescents

PURPOSE: this study evaluated the effects of a multidisciplinary program on autonomic modulation in overweight or obese children and adolescents. METHODS: fifteen individuals with 10,93 ± 2,28 years were submitted to autonomic evaluation using heart rate variability before and after a program based on physical exercises for three months, three times a week, 60 minutes per session and psychological and nutritional counseling. Data was analyzed using the paired t-test or Wilcoxon test and the level of significance was set at P < 0.05. RESULTS: multidisciplinary program was able to promote benefits in autonomic modulation observed thought temporal (SDNN: 39,96 ± 10,33 x 49,44 ± 12,31; p = 0,019; rMSSD: 28,97 ± 11,50 x 37,26 ± 11,17; p = 0,018), spectral (LFnu: 64,49 ± 12,21 x 56,74 ± 11,18; p = 0,014; HFnu: 35,50 ± 12,21 x 43,25 ± 11,18; p = 0,014) and geometrical (SD1: 20,51 ± 8,13 x 26,36 ± 7,90; p = 0,018 SD2: 52,31 ± 13,04 x 64,58 ± 16,33; p = 0,031) indices in overweigh and obese children and adolescents. Also, after the intervention there was a reduction on resting heart rate (88,53 ± 9,24 x 83,09 ± 7,93; p = 0,023) and there were changes in the classification of overweigh 26,67% x 46,66% and obesity 73,33% x 53,33%, although not significant changes in body mass index. CONCLUSIONS: exercise program together with nutritional and psychological counseling is able to promote benefits in autonomic modulation in children and adolescents who are overweight or obese.

OBJETIVO: avaliar a influência de um programa multidisciplinar na modulação autonômica de crianças e adolescentes com sobrepeso e obesidade. MÉTODO: quinze indivíduos com 10,93 ± 2,28 anos foram submetidos a avaliação da modulação autonômica por meio da variabilidade da frequência cardíaca antes e após um programa de atividades físicas conduzido por três meses, com frequência de três vezes na semana por 60 minutos cada sessão, associado com aconselhamento nutricional e psicológico. Para análise estatística foi utilizado teste T para dados pareados ou teste de Wilcoxon com significância de p < 0,05. RESULTADOS: o programa multidisciplinar foi capaz de influenciar positivamente a modulação autonômica o que pode ser observado por índices temporais (SDNN = 39,96 ± 10,33 vs. 49,44 ± 12,31; p = 0,019; rMSSD = 28,97 ± 11,50 vs. 37,26 ± 11,17; p = 0,018), espectrais (LFnu = 64,49 ± 12,21 vs. 56,74 ± 11,18; p = 0,014; HFnu = 35,50 ± 12,21 vs. 43,25 ± 11,18; p = 0,014) e geométricos (SD1 = 20,51 ± 8,13 vs. 26,36 ± 7,90; p = 0,018; SD2 = 52,31 ± 13,04 vs. 64,58 ± 16,33; p = 0,031) de variabilidade em crianças e adolescentes com sobrepeso e obesidade. Adicionalmente, após a intervenção houve redução da frequência cardíaca de repouso (88,53 ± 9,24 vs. 83,09 ± 7,93; p = 0,023) e mudanças na classificação da obesidade dos indivíduos para sobrepeso 26,67% vs. 46,66% e obesidade 73,33% vs. 53,33%. Apesar disso, não houve diferença significante no índice de massa corporal. CONCLUSÕES: um programa de exercícios associado com aconselhamento nutricional e psicológico foi capaz de promover benefícios na modulação autonômica em crianças e adolescentes com sobrepeso e obesidade.

Impact of obesity on autonomic modulation, heart rate and blood pressure in obese young people.

INTRODUCTION: Obesity can be understood as a comorbidity of increasing systemic impact, including a deficit in the autonomic nervous system. OBJECTIVE: To analyze cardiac autonomic behavior and hemodynamic parameters in obese young people. METHODS: 92 individuals (20.58±1.48 years) were evaluated, divided into two groups: obese and eutrophic. Heart rate (HR) was captured for 30 min in the supine position whilst breathing spontaneously. Blood pressure (BP) values were obtained prior to performance of the protocol. For the autonomic analysis, 1000 beats were used for the calculation of heart rate variability indices in the time (Mean RR, SDNN and RMSSD) and frequency (LF, HF and LF/HF) domains, in addition to the Poincaré plot (SD1, SD2, SD1/SD2 and qualitative visual analysis). RESULTS: The obese group presented higher baseline BP and HR values compared to the eutrophic. Regarding autonomic modulation a significant decrease was observed in the RMSSD; SD1, HFms and HFnu indices in the obese group, indicating a decrease in vagal activity and reduced SDNN and SD2 rates, with statistical significance for the former, suggesting a reduction in overall variability. The high value of the LFnu index and decrease in Mean RR in the obese group pointed to relative sympathetic predominance in these individuals. The visual analysis of the Poincaré plot showed less dispersion of the points in the obese group. CONCLUSION: The obese group presented higher BP and HR values at rest and autonomic impairment, characterized by a reduction in parasympathetic activity and relative predominance of sympathetic activity.