Introduction: The EPInfant scale has been validated for the perceptual estimation of physical exer tion in Chilean children, but its usefulness for self-regulation of exercise intensity is unknown. The objective of the study was to evaluate the criterion validity of the EPInfant scale to regulate and re produce exercise intensity in a sample of healthy children.
Subjects and method: 15 children between the ages of eight and 12 were selected for an incremental exercise test (IET) and three perceptually regulated exercise tests (PRET) on a treadmill. The tests were performed with a 48-hour interval between them. In the PRET, the exercise load was adjusted perceptually for five minutes, randomly considering levels 3, 6, and 9 of the EPInfant scale. The average heart rate (HR) during PRET was considered as the perceptually reproduced intensity. Variance analysis, simple linear regression, and reliability analysis were used to determine the reproducibility of HR during PRET.
Results: There was a significant difference in HR between perceptual levels during PRET (p < 0.001). Additionally, a correlation was observed between HR during the IET and the PRET (r = 0.83, r2 = 0.69). The intra class correlation coefficient was 0.76, 0.83. and 0.93 at perceptual levels 3, 6, and 9; and the mean dis cordance between HR during the IET and the PRET was -2.4 beats/min.
Conclusion: In the studied sample, the EPInfant scale was valid to allow the perceptual regulation and reproduction of exercise intensity in a treadmill.