Relationship between Television Time and Risk of Cardiovascular Event——Cross-study Based on Heart Rate Recovery and Heart Rate Variability

Objective:Heart rate recovery and heart rate variability are valuable predictors for cardiovascular event risk.The aim of this study was to ascertain the relationship between television time and cardiovascular risk.Method:A total of 533 healthy female adult were enrolled in the study.They were not participated in regular physical exercise in the past.Cubital vein blood was obtained for determination of blood glucose and lipid profile.Television time was obtained by aquestionnaire.Resting HRV data was collected and analysis.All subjects underwent aprogressive cycle test for determining peak oxygen uptake(VO2peak)and heart rate recovery at 1,2and 3 min(HRR and △HRR).Subjects were divided into L group(≤0.30h/day),M group(0.31~2.00h/day)and H group(>2.0h/day)according television time.The anthropometrics,HRR and HRV were compared between groups.Result:The female adults with television time above 2h/day had higher BMI,waist circumference,waist-to-hip ratio,blood pressure and triglyceride level,lowerVO2peak and HRV,slower HRR.Television time was positive correlated with subjects' age(r=0.458,P<0.05),and negative correlated with △HRR1(r=-0.155,P<0.05),△HRR2(r=-0.141,P<0.05),△HRR3(r=-0.146,P<0.05),andVO2peak(r=-0.100,P <0.05).Conclusion:Female adults with a longer television time and slower HRR,had higher risk of cardiovascular event.Compared with HRV,HRR would be more sensitive to predict the cardiac event.