Recuperação da frequência cardíaca após diferentes protocolos de treino em circuito e sua relação com a variabilidade da frequência cardíaca de repouso em mulheres pós-menopausadas fisicamente ativas

Abstract

The menopause is marked by physiological hemodynamic and metabolic changes in woman. However, long-term effects of estrogen deficit that could possibly lead to serious diseases, such as cardiovascular disease, are the problems that concern us the most. The estrogen replacement therapy is a way to reduce the consequences of hormone deficiency and exercise training contributes significantly to the reduction of cardiovascular risk, particularly on cardiac autonomic function. The investigation of the post-exercise recovery heart rate (HR) magnitude is a way to assess the autonomic cardiovascular integrity. The aim of this study was to assess the effect of three different types of circuit training on the full vagal reactivation in menopausal women that not receiving and receiving hormonal replacement treatment. Eighteen trained women with 57.7±1.7 years old were divided in two groups, as follows: without (GNHT, n=09) and with hormone therapy (GWHT, n=05). Menopausal women had an aerobic circuit with intensity of 60-70% of maximum HR, resistance circuit with intensity of 60% of maximum voluntary load and mixed aerobic and resistance circuit. Were evaluated the HR and HR variability (HRV) at rest and after different types of circuit training and full vagal reactivation. ANOVA one way to repeated measures was applied. The level of significance was set at 5%. The group of menopausal women who received hormone therapy had a higher resting bradycardia, as well as a sympathetic reduction and an increase in vagal modulation of HRV. After the orthostatic test, however, we noted a lesser response of HR, the sympathetic and parasympathetic modulation measured by means of spectral analysis in women without hormone therapy. The mean of values of HR during exercise were higher in resistance circuit compared to aerobic, independent of hormone replacement. After the exercise, however, recovery of HR was faster in aerobic circuit in comparison with other circuit training. After the resistance and mixed sessions of circuit training, the full vagal reactivation occurred later in relation to the aerobic circuit. When separated by hormone therapy, the group with hormonal replacement had a full vagal reactivation very fast in relation to women with hormonal therapy. In conclusion, our results suggested that the type and intensity of exercise training influence in full vagal reactivation and consequently in heart rate on period of post-exercise recovery. Furthermore, hormone replacement therapy in menopause has a role important on the autonomic modulation of heart rate in both at rest and post-exercise period by different circuit training.