Study On Indirect Assessment Of VO2max By Resting Heart Rate Combined With Body Composition

Purposes:Maximum Oxygen Uptake(VO_2max)is an important index for assessing the function of the body.The direct test method requires the subject to wear a breathing mask and complete exhaustive exercise at the same time,however,there is a certain danger and the equipment is expensive.And the current indirect estimation algorithm generally requires the subject to perform sub-maximal exercise,or use a single index to calculate VO_2max,which has a large error.Therefore,it needs to be tested by professionals in the laboratory,which is difficult to popularize.In this study,by comparing the correlation between Resting Heart Rate（RHR）,body composition index with VO_2max which was tested by the Bruce treadmill protocol.The VO_2max regression model is proposed to provide a simple and new method for indirect estimation of VO_2max,provide theoretical support for public fitness,monitor physical fitness,and guide physical exercise.Methods:A total of 80 adults were used as the research object,of which 67 were tested as the modeling group and 13 were tested as the test group.The Bruce protocol was used to test the subjects with increasing load on the treadmill to determine VO_2maxand RHR;Inbody-BSM370 was used to measure their height,weight and Body Mass Index（BMI）;by dual energy X-ray（DEXA）method to measure Body Fat Percentage（BF%）,Free Fat Mass（FFM）.Correlation analysis was performed on the above indicators and VO_2max to establish an optimal regression model for predicting VO_2max.Results:（1）This study performed an independent sample T test on each index in the modeling group by gender and age.The results showed that height,weight,BMI,BF%,FFM,and VO_2max all had significant gender differences,with the exception of BF%.The indexes were significantly higher than that of women;there were significant age differences in height,weight,BMI,BF%,and VO_2max in the young and middle-aged groups.Except for height and VO_2max,the weight,BMI,and BF%middle-aged groups were significantly greater than the youth.（2）Pearson correlation test was performed on body composition index and VO_2max.Among them,height,weight,BMI,and FFM were significantly positively correlated with the absolute value of VO_2max（r=0.752,0.726,0.385,0.981）,and BF%and VO_2max were absolute significantly negative correlation（r=-0.749）.（3）（1）VO_2max（L/min）=0.487+0.058*FFM+（-0.021）*BF%,R²=0.868,Adjust R²=0.864;（2）VO_2max（L/min）=1.482+（-0.022）*age+0.616*sex（male=1,female=0）+（-0.009）*RHR+0.034*weight（kg）,R²=0.790,Adjust R²=0.776;（3）VO_2max（L/min）=1.288+0.962*sex（Male=1,Female=0）+（-0.020）*Age+0.068*BMI,R²=0.706,Adjust R²=0.692.Conclusions:（1）Significant gender and age differences between functional indicators and body composition;（2）Significant correlations between body composition indicators（height,weight,BMI,BF%,FFM）and VO_2max;（3）RHR combined with body composition can effectively predict VO_2max among them,the RHR and weight-VO_2max models can better predict the VO_2max of the general population.