Effects of Increased Physical Activity and Mild Calorie Restriction on Heart Rate Variability in Obese Women.

Abstract
The effects of exercise and mild calorie restriction on heart rate variability (HRV) were investigated in 12 mildly obese, normotensive Japanese women aged 45.8±4.2 (SEM) years with a body mass index (BMI) of 27.3±0.4 kg/m2. The subjects participated in a 3-month program aimed at increasing physical activity and modifying eating behavior (intervention group). The control group consisted of 12 women (age 50.1±4.8 years, BMI 27.2±0.6 kg/m2) who did not attend the program. The frequency domain of HRV was calculated from 5-min Holter recordings while the subjects rested in a supine position. After 3 months, BMI decreased to 25.0±0.5 kg/m2 (ppr=−0.49, p<0.05). The combination of exercise and mild calorie restriction led to changes in HRV indicative of an improvement in parasympathetic modulation.