Relationships Between Body Composition, Abdominal Muscle Strength, And Well Defined Abdominal Muscles

Abstract

BACKGROUND Physically fit individuals may desire to have well defined abdominal muscles (also known as “6 Pack Abs”). They seek to obtain 6 Pack Abs through numerous exercises that strengthen and tone the abdominal muscles. It has also been purported that to have 6 Pack Abs an individual must have low amounts of total body fat. However, there has been little to no research to determine the amount of body fatness or abdominal muscle strength necessary to have 6 Pack Abs. PURPOSE: The aim of this study was to evaluate the relationship between total and regional body fatness, abdominal muscle strength, and the aesthetic quality of an individual's abs. METHODS: 56 male and 31 female subjects between the ages of 19 and 35 years old were recruited for measurement of body composition via dual-energy x-ray absorptiometry, abdominal skinfold measurement, abdominal muscle strength assessment through a 60 second sit up test, and a photograph of the subject’s bare abdomens. The photographs were then scored on a 10 point scale for overall quality of 6 Pack Abs based on visual appearance for symmetry, muscle mass, and definition (total possible score of 30 points). Regression analysis was used to determine what factors predict 6 Pack Ab score. RESULTS: The strongest predictor of 6 pack ab score for women was having a low percent of android body fat (r2 = 0.52), followed by total percent body fat (r2 = 0.46), abdominal skinfold thickness (r2 = 0.45), and percent of gynoid body fat (r2 = 0.33). The strongest predictor of 6 pack ab score for males was having a low percent of android body fat (r2 = 0.43), followed by total percent body fat (r2 = 0.38) and then abdominal skinfold thickness (r2 = 0.33). 1 minute sit up performance did not significantly predict 6 pack ab score. CONCLUSION: The present data suggest that the strongest predictor of 6 pack ab score is having a low percent of android body fat followed by total percent body fat. Since total body fatness can be influenced by diet and exercise, but body fat distribution is determined by genetics, 6 pack abs may be an unattainable goal for some individuals. Furthermore, the present data indicate that performance on the 1 minute sit up test is not a significant predictor of 6 pack ab score, suggesting that abdominal muscle strength is not a significant influence on 6 pack abs in physically active individuals.