Heart rate recovery at 1st min after graded exercise an indicator of parasympathetic function in healthy obese young adults

ABSTRACT

Background: Heart rate recovery at 1st min (HRR 1 min) after graded treadmill exercise (GTX) is a predictor of parasympathetic function. Impaired HRR 1 min and obesity are strong predictors of metabolic syndrome and cardiovascular disorders. This study is done to asses HRR 1 min on apparently healthy obese young adults with body mass index (BMI) ?30, without any other metabolic syndrome components. Aims and Objectives: The objective of this study was to assess the parasympathetic function by estimating HRR 1 min after exercise in apparently healthy obese young adults of 18–30 years of age without any metabolic syndrome components and is compared with age- and gender-matched controls with normal BMI. Materials and Methods: Fifty obese young adults with BMI ?30 without any other metabolic syndrome component and 50 age- and gender-matched controls with BMI ?24.9 were selected and subjected to GTX according to modified Bruce protocol. Maximum heart rate reached during exercise (HRmax) and heart rate at 1st min of recovery phase (HR1min) were recorded. HRR 1 min was calculated as HRmax-HR1min and was analyzed. Results: This study showed significantly attenuated HRR 1 min in obese young adults compared to age- and gender-matched controls (mean 24.02 ± 8.87 vs. 42.42 ± 5.3, P < 0.001). Conclusion: HRR 1 min was significantly decreased in obese young adults, indicating attenuated parasympathetic function, who are at higher risk of developing chronic cardiovascular and other metabolic disorders.