Relationship of VO2reserve with heart rate reserve and rating of perceived exertion in 10-17 years healthy girls and boys

 
The aim of this study was to investigate the effects of gender and age on relationship between VO2 Reserve (%VO2R) with heart rate reserve (%HRR) and rating of perceived exertion (%RPE) in 10-17 years healthy individuals. Ninety six healthy children and adolescents (Mean+SD, age, 13.5+2.2 years; height, 153.6+12.4 cm; weight, 48.6±13.1 kg) were voluntarily participated in this study. Subjects attended the laboratory in two separate sessions. At the first session resting oxygen consumption (VO2rest), resting HR (HR rest), assessment of body composition and familiarization with testing protocol were carried out and in the second session all subjects performed a graded treadmill ramp protocol. For each subject, resting data, mean of 30 s measurements and maximal VO2, HR and RPE were used to determine two types of linear regression (%VO2R vs. %HRR and %VO2R vs. %RPE) and to calculate slopes and intercepts, Mean and standard error for slope and intercept were calculated and compared with the line of identity (y = x, slope 1, intercept_0). The results showed that there are positive and significant correlations between VO2R% with HRR% (r-0.97) and RPE% (r-0.92). The correlations between VO2R and HRR were 96% and 98% in boys and girls, respectively; while between VO2R and RPE were 90% and 95% in boys and girls, respectively. Gender and age result in significant differences in linear regression for VO2R-HRR in relation to line of identity. Gender has a significant effect on the linear regression relationship for VO2R-%RPE; and age has an effect when the data are adjusted based on the gender. Based on the findings of the present study it could be concluded that in spite of high accuracy for RPE%, in children and adolescents, %HRR compared to RPE% provides more accurate prediction of %VO2R and that both of these variables can be used to prescribe and monitor exercise intensity. The RPE scale is also can be used slightly less accurate than %VO2R to prescribe and monitor exercise intensity. Meanwhile, the precision of these predictions are more accurate in girls than boys.