Purpose: The purpose of this study was to establish a standardized protocol for the heel-rise test for children, document reliability and validity of this protocol, and establish beginning normative heel-rise values for typically developing children between the ages of 5 and 12 years. Subjects: The sample consisted of 57 typically developing children and 34 children with plantarflexion weakness. Each subject group was divided into four age groups: 5 to 6, 7 to 8, 9 to 10, and 11 to 12 years. Methods: All 91 children participated in three tests of lower extremity strength: the heel-rise test, the vertical jump test, and a force test measured with a hand-held dynamometer. The heel-rise test involved a laser pointer, mounted on a tripod base, projecting a 2 foot horizontal line on a wall and marking 50% of each subject’s maximum vertical plantarflexion excursion. Children faced the wall used fingertip support for balance, and performed heel-rises to exhaustion, breaking the laser beam with each repetition. Vertical jmp height was measured and recorded along with the force values obtained with a hand-held dynamometer from three isometric plantarflexion contractions. The reliability assessment included examination of intrarater, interrater, and test-retest reliability. Both construct and concurrent validity were examined and reported. Finally, beginning normative values along with analyses of the relationships between the number of heel-rise repetitions and gender, age, height, weight, and activity level of the subjects were examined. Results: The Intraclass correlation coefficient was 0.997 for intrarater reliability and the ICC measured 0.99 for interrater reliability and 0.911 for test-retest reliability. Pearson product moment correlation coefficients were 0.693 and 0.454 when heel-rise scores were compared to the vertical jump and handheld dynamometer values respectively. Children with weakness performed significantly fewer heel-rises than typically developing children. In the typically developing group, the mean number of heel-rises increased linearly with age: 12.7, 18.6, 22.1, 31.6 repetitions for the 5-6, 7-8, 9-10, and 11-12 year old children respectively. Scores from the two youngest age groups differed significantly from the scores achieved by children in the oldest age group. Children age 5 to 8 years performed a mean of 15.1 (plus or minus) 5.4 repetitions and children age 9 to 12 years performed a mean of 27.7 (plus or minus) 11.7 repetitions. Males performed a greater number of repetitions than females. Age, height, and weight were all significantly and moderately correlated with the number of heel-rises. No significant correlation was found between heel-rise repetitions and activity level of the subjects. Conclusions: A standardized protocol for the heel-rise test in children is documented. This protocol is both reliable and valid for use in 5 to 12 year old children with and without plantarflexion weakness. The mean results may serve as guidelines for assessing performance until normative values are established with a larger number of children. The influence of age, gender, height, weight, and activity level should also be further explored with a larger sample.
