Heart rate responses during exercise in obese adolescents: relation with cardiovascular health

Abstract

In adults with obesity, changed peak heart rate during exercise is independently related to an elevated risk for adverse cardiovascular events. However, the prognostic relevance in adolescents with obesity remains to be explored.

The goal of this project was to study the association between HR responses and cardiac function, cardiovascular autonomic function, atherosclerosis and cardiac electrophysiology to assess the importance of HR responses during exercise as a prognostic tool for cardiovascular disease in obese adolescents.

Twenty-four obese (OG BMI: 32.1 ± 4.3 kg/m2) and 24 lean (LG BMI: 19.6 ± 2.5 kg/m2) adolescents performed a maximal cardiopulmonary exercise test (CPET). Groups were age and gender matched. Transthoracic echocardiography was performed, carotid intima media thickness was measured. Fasting blood samples were collected. Multivariate regression was used to explore relationships between CPET and secondary measurements.

HRpeak was not different between two groups (p=0.97). Heart rate reserve (p=<0.01) and heart rate recovery at 30 (p=0.03), 60 (p=0.02) and 120 seconds (p=<0.01) after exercise were decreased in the OG. Maximal power output was lower in the OG(p=0.01). HRreserve and HRR were associated with Significant alterations in HRreserve and HRR suggest cardiovascular autonomic function is distorted in obese adolescents. HRreserve and HRR might be of prognostic value for cardiovascular disease risk in obese adolescents.