Associations between ACE Genotypes, +8.5 Gz Tolerance, and Body Composition in F-15 Pilot Candidates

INTRODUCTION: Pilots' +8.5Gz tolerance is related with their selection, safety and special mission suitability. The preliminary study about F-15 pilot candidates were rare, especially related with genetic effect like ACE (angiotensin converting enzyme) gene. BACKGROUND: This study aimed to investigate the associations between the +8.5 Gz test qualification and angiotensin converting enzyme (ACE) genotypes in Korean F-15 pilot candidates for pilot special mission suitability and cadet body composition education. MATERIALS AND METHODS: We performed +8.5Gz test (15 seconds), target gene (ACE) identified and body composition measurements from twenty Korean F-15 pilot candidates (ages 23.0-28.6 years). The +8.5Gz test results (pass and not-passed), body composition parameters and their relationship with the ACE genotype were evaluated. RESULTS: Four (20%), six (30%), and 10 (50%) pilots had the DD, DI, and II genotypes based on the ACE gene identification results, respectively. Ten (50%) pilots passed by maintaining consciousness during the +Gz test. Of them, three (75%, 3/4), four (66.7%, 4/6), and three (30%, 3/10) had the DD, DI, and II genotypes (P < .05, DD > II), respectively. Compared with other genotypes, the DD genotype was associated with overall higher values of body composition indices, and this association was more prominent among pilots who passed the +8.5 Gz test. DISCUSSION: In some ethnic groups, the DD genotype has been found to have an effect on elite players' high-intensity performance, including muscle power and strength. The DD genotype exhibited the highest performance in terms of passing rate, longest mean breathing interval(s), and higher values of body composition parameters in pilots who passed the +8.5 Gz test. CONCLUSIONS: In this study, the group with the DD genotype exhibited a higher pass rate and heavier body composition parameters than the group with the II genotype. These results require further investigation to determine their significance and applicability in other ethnic groups.