A rating of perceived exertion scale using facial expressions for conveying exercise intensity for children and young adults.

Objectives: To design a rating of perceived exertion (RPE) scale using facial expressions and assessed the validity of the scale for both children and young adults.

Design: Pearson moment-product correlation analysis was used to assess the correlation among heart rate (HR), RPE and pedaling workload.

Methods: Fifteen children and 15 young adults participated in the study. Each participant randomly performed 5 pedaling tests with one repetition based on their submaximal acceptable workloads. Under each load condition, participants pedaled on a cycle ergometer for 10min; subsequently, participants completed Borg category ratio (CR10) or facial RPE (FRPE) scale assessments. Participants' heart rates (HR) were used to compare their scores on the Borg CR10 and Facial RPE scales.

Results: The results show that both Borg CR10 and FRPE scales reflected different pedaling workload levels. For young adults, HR positively correlated with both RPE scores under the various workload levels (r=0.989 and 0.977, all p<0.005); for children, only FRPE scores were positively correlated with HR (r=0.908, p<0.05). In other words, FRPE scores effectively reflected the HR of children, whereas Borg CR10 scores did not.

Conclusions: The children may not understand words as effectively as young adults did, however, they understand facial expressions. The FRPE scale proposed in this study may be available in some special cases because it can assess those who cannot comprehend the written words used for the scale.