Age-Related Differences in OMNI-RPE Scale Validity in Youth: A Longitudinal Analysis

RPE scales are used in exercise science research to assess perceptions of physical effort. RPE scale validity has been evaluated by assessing correlations between RPE and physiological indicators. Cross-sectional studies indicate that RPE scale validity improves with age; however, this has not been studied longitudinally.

This study aimed to examine age-related trends in OMNI-RPE scale validity, using a longitudinal study design, and HR and oxygen uptake (V˙O2) as criterion measures.

Participants performed eleven 5-min activity trials at baseline, 12-, 24-, and 36-month follow-up (V˙O2 data: N = 160; HR data: N = 138). HR and V˙O2 between minutes 2.5 and 4.5 of each activity were recorded. At the end of each activity, participants reported RPE. Children were stratified into the following age-groups: 6-8, 9-10, 11-12, and ≥13 yr. Within-subject correlations between OMNI-RPE and HR/V˙O2 were calculated at each time point. Differences between correlations for consecutive time points were evaluated using 95% confidence intervals.

Among children age 6-8 yr at baseline, correlations progressed from 0.67 to 0.78 (V˙O2) and from 0.70 to 0.79 (HR) for 36 months. Among children age 9-10 yr at baseline, the mean within-subject correlation was 0.78 at baseline and 0.81 at 36-month follow-up. Among children age 11-12 and ≥13 yr at baseline, OMNI-RPE ratings demonstrated strong validity (r ≥ 0.82) at each time point.

For the 36-month follow-up, OMNI-RPE scale validity improved among children age 6-8 yr at baseline and remained strong among children age 9-10, 11-12, and ≥13 yr at baseline. Moderate correlations for the youngest participants suggest that caution should be used when interpreting OMNI-RPE reports from children younger than 8 yr.