Role Of Aerobic Exercise On Cardiac Autonomic Modulation And Adipokines In Polycystic Ovary Syndrome

Abstract

Women with Polycystic Ovary Syndrome (PCOS) present substantial weight gain that may increase the risk of developing cardiovascular diseases. Hormonal, metabolic and cardiac autonomic changes also occur and increase the risk of these diseases. However, despite advances, the effects of aerobic exercises on the different aspects of this syndrome are still unknown, especially when the body fat percentage is considered. PURPOSE: To investigate the effects of aerobic exercise on hormonal and metabolic aspects and cardiac autonomic modulation in women with PCOS with different percentages of body fat. METHODS: Women with PCOS (N=60) and without PCOS (control, N=60), between the ages of 18 and 39 years, were divided into three groups, according to their body fat percentage (22-27%, 27-32% and 32-37%). The participants were submitted to assessment of the following parameters before and after the aerobic physical training (16 weeks); body composition, fasting glucose and insulin, androgens, leptin, adiponectin, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and the analysis of heart rate variability (HRV). RESULTS: Women with PCOS had increased serum levels of androgens, insulin (insulin resistance), leptin, TNF-α and IL-6 associated with reduced serum levels of adiponectin. Autonomic assessment revealed that these women also exhibited an impaired autonomic modulation characterized by reduced HRV, but mainly in high-frequency oscillations (HF=0.2-0.5Hz), corresponding to vagal modulation. These findings were directly associated with the body fat percentage; however, according to some parameters evaluated (insulin, TNF-α, IL-6 and HRV), PCOS seems to play a key role. In turn, the aerobic physical training was effective in improving almost all the parameters evaluated, except the serum levels of androgens and TNF-α. CONCLUSIONS: The results showed that PCOS has been found to be associated with significant endocrine/metabolic disturbances and cardiovascular autonomic dysfunction, which are exacerbated by overweight. Aerobic physical training proved to be an effective treatment for most parameters evaluated and should be prescribed as an adjunct treatment for PCOS, the same way it has been used to treat chronic degenerative diseases. Supported by CNPq (457216) and FAPESP (07561-0) Grants