Core-strengthening exercises have become an integral foundation of most training programs, however when developing normative data for core-strength it cannot be assumed that recommendations are appropriate for all populations. Therefore, the purpose of this study was to develop normative core strength data for the Korean population in comparison to established American norms as measured by the Abdominal Test and Evaluation Systems Tool (ABTEST). Core-strength data collected from American (males: n = 84, females: n = 94) and Korean (males: n = 196, females: n = 212) populations were used for initial comparisons and development of population norms. When using ABTEST for evaluation, subjects were placed with the knees and hips at 90-degree angles with a force transducer located directly over the xiphoid process. Force was measured using a secured, cushioned load cell and was expressed in kg. Absolute force, relative force (per unit body weight), and fatigue (force decline over a 10-second contraction) were evaluated between genders for both population groups using unpaired t-test. Normative data were developed by organizing outputs from American and Korean subjects into 10th, 25th, 50th, 75th, and 90th percentiles. When evaluating absolute strength, American males (p < .001) and females (p = .003) demonstrated significantly higher strength compared to gender and age matched Koreans. Similar significant differences (p < .001) were observed in males when evaluating relative strength, however, relative differences were not detected in females. Fatigue index demonstrated a reverse trend compared to absolute strength. Korean females demonstrated a 28% lower fatigue index than American females while Korean males show a 30% lower fatigue index than American males. When developing normative strength values for the Korean population, Korean males exhibited significantly lower scores at each percentile compared to their American, male counterparts. With the exception of the lowest percentile (10%), the same pattern existed for Korean females. Current data support the concept that analysis of different cultures is necessary to develop normative data for populations. Future research must not only evaluate different cultures, but also ensure that the evaluated subset is representative of the population.
