Observation of perceived exertion in children using the OMNI pictorial scale

Concurrent and construct validity of a kinematic exertional observation procedure was examined for 10- to 14-yr-old female (N = 22) and male (N = 22) healthy children.

A load-incremented treadmill test protocol employing speed/grade changes every 3 min was used. RPE for the overall body (RPE-Overall), legs (RPE-Legs), and chest (RPE-Chest) were simultaneously estimated by an independent observer and self-rated by a subject during each treadmill stage using the Children's OMNI-Walk/Run Scale. Subjects' HR and oxygen consumption (VO2) were measured during each stage. Concurrent validity was established by correlating the observer's RPE with the subject's HR and VO2. Construct validity was examined by correlating submaximal RPE estimated by the observer with RPE estimated by the subject.

The range of responses for the females and males was VO2 = 18.4-43.5 mL x kg(-1) x min(-1), HR = 121-185 bpm, and OMNI Scale RPE- (Overall, -Legs, -Chest) ranging from 1 to 9. Observer RPE (Overall, -Legs, -Chest) for the female and male subjects ranged from 1 to 9. For both female and male groups regression analyses indicated that observer's RPE distributed as a positive function of subject's HR and VO2; r = 0.80-0.91 (P < 0.01). Observer's RPE distributed as a positive function of subject's RPE for both females and males; r = 0.87-0.92 (P < 0.01).

Results support the validity of a direct kinematic observation procedure to estimate OMNI Scale RPE for female and male children performing treadmill exercise. Exertional observation provides an unobtrusive perceptual estimate of exercise intensity and could be included in standardized physical activity assessments for children.