Effect of Obesity on Cardiac Function and Exercise Changes in Adults

Objective: The purpose of the study was to evaluate the impact of adults obesity on cardiac structure and function at rest and during exercise. Methods: 130 adults (29 male, 101 females) aged 40~60 years were recruited in Beijing, dividing into 3 groups according to BMI, including 1 lean group (n=57) , 1 overweight group (n=56) and 1 obesity group (n=17) . After resting echocardiography, all subjects performed a horizontal exercise test that the initial load was 25 W, increasing 25 W every two minutes. Conventional echocardiography was acquired at rest and each workload. Results: 1) Compared with the lean group, the obesity group showed increasing interventricular septal thickness (IVSd) , left ventricular end-diastolic dimension (LVIDd) , left ventricular posterior wall thickness (LVPWd) , left ventricular end-diastolic volume (EDV) , left ventricular mass (LVM) , left ventricular mass index (LVMI) , heart rate (HR) , stroke volume (SV) and cardiac output (CO) (P< 0.01) . 2) Left ventricular hypertrophy in obese adults is much higher than the normal weight or overweight. 3) Significant main effects for group indicated obese participants had higher CO and SV during incremental exercise to exhaustion compared with their normal-weight peers (P< 0.01) , despite EF, HR had no significant differences among the groups (P> 0.05) . Conclusions: Our findings suggest that alterations of cardiac structure and function in overweight adults were similar to those in obese, including increased left ventricular mass and cardiac dysfunction. Although CO and SV were higher in obese adults, lower cardiac reserve function and impaired heart rate recovery when compared to matched, normal-weight adults. The abnormal enhancement of cardiac function in obese people at rest and during exercise needs to be further research.