The Study On Obese Adolescents’ Heart Automonic Nerve Function Of Different Exercise Load

In this study, by comparing the normal, overweight and obese adolescents’HRV variation in different exercise load to resaerch the influence of obesity and exercise load with HRV.Thus we hope HRV index in sport to be as one of adolescents’sports risk indexs.This study choose41male students of grade one from a middle school in Beijing Haidian. Using PAR-Q questionnaire to exclude dizziness、 chronic infectious disease、heart disease、limb joint dyscinesia, Divided the students into normal, overweight and obese group.according the WGOC(Ji and Working Group on Obesity in China) standard and WHO boy、 girl wasting Screening critical point of different age. The normal group is control group. Before the test, wear polar watch and transmission belt for subjects. After relax10minutes, measure5minutes heart rate in the state of recumbent. Afterwards, let subjects ride on bicycle in50,75and100watts, Each load lasts for5minutes. After the test,record5minutes heart rate recovery.The result show the trend of HRV index of the three groups:(1). Before the test:obese group’s HF is less than the normal group, LF/HF is greater than the normal group (p<0.01), overweight group’s LF/HF is greater than the normal group (p<0.05);(2).50W:obese group’s TF is less than the normal group, LF/HF is greater than the normal group (p<0.01), VLF、 LF are greater than the normal group (p<0.05), overweight group’s LF/HF is greater than the normal group (p<0.05);(3).75W:obese group’s TF、 HF are less than the normal group, VLF、 LF and LF/HF are greater than the normal group (p<0.01), overweight group’s TF、HF are less than the normal group, LF is greater than the normal group (p<0.01), VLF is greater than the normal group (p<0.05);(4).100W:obese group’s TF、HF are less than the normal group, LF、LF/HF are greater than the normal group (p<0.01), VLF is greater than the normal group (p<0.05), overweight group’s TF is less than the normal group, LF/HF is greater than the normal group (p<0.01), VLF is greater than the normal group (p<0.05);(5). After the test:obese group’s TF、HF are less than the normal group, VLF、 LF are greater than the normal group (p<0.01), overweight group’s TF is less than the normal group, VLF is greater than the normal group (p<0.01)The conclusion are:(1). In the rest state, the balance of obese and overweight adolescents’autonomic nervous is change.(2). In the medium and hig intensity exercise, obese adolescents’autonomic nerve integrated function and vagal tone are less than normal adolescents, the vagal tone is greater than normal adolescents.The imbalance of sympathetic nervous and nervi vagus is greater than normal adolescents. Represents the excitement of the sympathetic nervous.(3). obese adolescents’HRV is lower than the normal adolescents, vagal tone decrease and sympathetic tone ascends. Obesity can affect adolescents’cardiac vagal tone and the balance of sympathetic nervous and nervi vagus, increases the risk of cardioascular disease for obese adolescents.