Although the influence of adiposity indices and cardiorespiratory fitness (CRF) on heart rate variability (HRV) has been demonstrated extensively, the causal link between the changes in adiposity as well as in CRF and the alterations in cardiac autonomic function is unclear. Thus, this study aimed to assess the correlation between the changes in adiposity and CRF and the alterations in HRV after 12-week exercise training. Twenty obese sedentary men aged 20.5±1.2 years were randomly assigned into 2 groups (n=10 each): the control (CG) and the exercise group (EG). The EG trained 60 min of combined aerobic, anaerobic and strengthening exercise, 4 sessions/wk for 12 weeks, whilst the CG remained relatively inactive. Measurements of resting HRV, body composition, and peak oxygen consumption (VO_2peak) were obtained at baseline and after the 12-week training program. Compared with CG, the exercise training significantly reduced adiposity indices and improved vagal-related HRV variables and VO_2peak. Significant correlations were observed between changes in HRV variables and adiposity indices and VO_2peak changes. Stepwise regression analysis revealed that changes in a Poincaré plot index (SD1/SD2 ratio) predicted 32.4% of the variance in the relative VO_2peak changes. These findings suggest that obese sedentary young men achieved significant improvements in vagal activity, adiposity indices and aerobic fitness after the exercise training. The higher reduction in fat mass, especially central obesity, the greater alteration of vagal modulation. Moreover, the alteration in resting HRV is a possible predictor for adaptations to exercise training in obese sedentary young men.

[Purpose] Obesity and hyperglycemia play roles in the impairment of pulmonary function in type 2 diabetes mellitus (T2DM) patients. Low-intensity exercise is known to reduce body fat and improve hyperglycemia. The arm swing exercise (ASE), a low-intensity exercise, is easy and convenient to perform without any equipment and is suitable for daily practice. Therefore, we aimed to investigate the effects of ASE on lung function and obesity in overweight T2DM patients. [Subjects and Methods] Twenty-four subjects continued their daily life routines for 8 weeks (control period), and then performed ASE for 8 weeks (30 minutes per day, 3 days per week) (ASE period). Pulmonary function tests were performed, and fasting blood glucose, haemoglobin A1c (HbA1c), lipid profiles, high-sensitive C-reactive protein (HSCRP), insulin concentration, and anthropometric parameters were measured before and after each period. [Results] After the ASE period, the forced vital capacity, forced expiratory volume in the first second of expiration, and maximal voluntary ventilation were increased when compared with after the control period. HbA1c, a low-density lipoprotein, malondialdehyde, oxidized glutathione, and the percent body fat were significantly decreased when compared with after the control period. However, other parameters, such as lung volume, anthropometric parameters, and fasting blood glucose, insulin, high-density lipoprotein, triglycerides, total cholesterol and glutathione concentrations, showed no differences between the two periods. [Conclusion] These data suggest that there is improvement of pulmonary functions in T2DM patients after ASE training.

Background: Imbalances of the autonomic nervous (ANS), the cardiovascular system, and ionics might contribute to the manifestation of The Brugada Syndrome (BrS). Thus, this study has aimed to investigate the cardio‐respiratory fitness and the responses of the ANS both at rest and during a sub‐maximal exercise stress test, in BrS patients and in gender‐matched and age‐matched healthy sedentary controls.Methods: Eleven BrS patients and 23 healthy controls were recruited in Khon Kaen, Thailand. They performed an exercise test on a cycle ergometer, and during the exercise, expired gas samples and electrocardiograms were collected. Blood glucose and electrolyte concentrations were analyzed before and after exercise. Then the heart rate variability (HRV) and the heart rate recovery (HRR) were analyzed from the electrocardiograms.Results: The BrS patients showed a higher parasympathetic activation during exercise recovery than baseline. They had a smaller level of sympathetic activation during the period of exercise recovery than the controls did. They also showed a significantly lower peak HR, HRR, and peak oxygen consumption than the controls (p<0.05). All subjects had a significantly lower percentage of peak oxygen consumption and respiratory exchange ratio during low‐intensity (p<0.01) and moderate‐intensity (p<0.05) exercise than during high‐intensity exercise. The BrS patients had mild hyperkalemia which is reduced according to the exercise.Conclusion: Thai BrS patients had a more rapid rate of restoration of the parasympathetic and smaller level of sympathetic activation after exercise. They had mild hyperkalemia which is reduced according to the exercise. Furthermore, they exhibited impaired cardio‐respiratory fitness.

[Purpose] This research aimed to investigate the relationship between aerobic capacity (VO2,peak) and cardiovascular risk factors in normolipidemic and dyslipidemic Thai men and women. [Subjects and Methods] We recruited 104 dyslipidemic and 100 healthy participants. Fasting blood samples were analyzed for lipid and blood glucose levels. Anthropometry, blood pressure, and body composition were measured before exercise. Each subject underwent exercise testing to determine VO2, peak. Heart rate (HR) was recorded throughout the exercise test. [Results] Dyslipidemic participants had a lower VO2, peak than normolipidemic participants (p<0.01). In normolipidemic male participants, VO2, peak was positively correlated with high density lipoprotein cholesterol (HDL-C) levels and negatively correlated with low density lipoprotein cholesterol (LDL-C) levels and triglycerides to HDL-cholesterol (TG/HDL-C) ratios; in females, VO2, peak was negatively correlated with age, total cholesterol, and LDL-C. In dyslipidemic males, VO2, peak was positively correlated with HDL-C levels and negatively correlated with age, LDL-C and TG levels, and percent body fat; in females, VO2, peak was positively correlated with resting HR and heart rate recovery and negatively correlated with age, TG/HDL-C, and waist circumference. [Conclusion] There was a relationship between aerobic capacity and cardiovascular disease risk factors in both normolipidemic and dyslipidemic participants. This relationship was affected by gender.

Exercise Therapy for Physical Therapist | InTechOpen, Published on: 2017-05-31. Authors: Naruemon Leelayuwat