Investigating the Correlation between Obesity Indices and Heart Rate Recovery After Exercise Testing

Background: Heart rate recovery (HRR) after exercise is a specific measure of the functioning of the autonomic nervous system. A rapid HRR immediately after exercise is associated with a lower risk of cardiovascular disease. Besides, there is a correlation between post-exercise HRR and cardiovascular risk factors. Objectives: This study investigated the correlation between obesity indices after exercise testing and HRR to evaluate the autonomic system and the risk of cardiovascular diseases. Methods: In this cross-sectional study, 108 non-random consecutive patients over 18 years old with indications for exercise testing were selected from those referred to Modarres Hospital in Tehran between 2021 - 2022. The patients were subjected to an exercise test, and the decrease in heart rate was recorded in the first and second minutes after the exercise testing. Then, the correlation between obesity indices and risk factors for cardiovascular diseases and the HHR was evaluated. Results: Based on our results, none of the obesity indices such as weight, height, BMI, neck circumference, waist circumference, hip circumference, WHR, ABSI, ABI, or BAI showed a significant correlation with the reduction of the heart rate one and two minutes after the exercise test. However, the heart rate reduction one minute after the exercise test was significantly lower in patients with a family history of heart disease. Also, the heart rate reduction two minutes after the exercise test was significantly lower in diabetic patients, hyperlipidemic patients, and patients with insufficient sleep. Conclusions: Although there was no significant correlation between obesity indices and heart rate reduction after exercise tests due to the harmful effects of obesity and overweight on cardiac function and its increasing prevalence, clinical trial studies will be beneficial in clarifying the effects of obesity indices on cardiac efficiency.