Results: Data was obtained from fifty runners (28 male, 25.8 ± 7.0 years). Sahrmann test score andfrequency of Exercise-related transient abdominal pain were significantly different between groups(p = 0.002) with asymptomatic runners having significantly higher Sahrmann test scores (stronger mus-cles) than weekly and yearly Exercise-related transient abdominal pain groups (p = 0.001, p = 0.02). Therewere significant between group differences for resting transversus abdominis thickness (p = 0.034) butnot for transversus abdominis thickness change (p = 0.555).Conclusions: Participants who had stronger trunk muscles and larger resting Transversus abdominis sizeexperienced Exercise-related transient abdominal pain less.