Dynamic trunk muscle endurance profile in adolescents aged 14-18: Normative values for age and gender differences

BACKGROUND: The selection and validation of age- and gender-specific criterion-referenced cut-points for abdominal endurance are still unclear. OBJECTIVE: To stablish normative values for abdominal endurance in adolescents by age and gender using the Bench Trunk Curl-up Test (BTC). Additionally, the reliability of the BTC was analyzed. METHODS: Two hundred and sixteen untrained high school students (104 males - 112 females) were grouped into five age strata. Participants performed the BTC twice with a rest period of 72 h. Descriptive statistics and percentile scores were determined for each gender/age strata. RESULTS: Males showed higher BTC scores than females (males: 90.07 +/- 32.65 repetitions; females: 73.43 +/- 27.74 repetitions), but no significant differences between age strata nor age * gender interaction were found. Significant differences for the BTC scores between sessions were found (T1 = 72.06 +/- 26.28 repetitions; T2 = 81.44 +/- 31.27 repetitions). The ICC was 0.82, whereas the typical error was 17.2%. CONCLUSIONS: Gender, but not age, is an important factor when abdominal endurance is compared between adolescents. Finally, the BTC is a reliable test, supporting the findings of this study. However, an extensive familiarization period to reduce the learning effect is necessary.