Contraction of the TrA leads to decreased abdominal circumference via increased tension of the thoracolumbar fascia.Thisdecreased abdominal circumference along with the cocontractionof the diaphragm and pelvic floor muscles produces an increasein intra abdominal pressure.Either or both of these vari-ables may be influencing factors on the mobility of the abdominalcontents. Therefore, we hypothesise that better TrA function mayreduce abdominal content mobility and contribute to a reducedincidence of ETAP. Consequently, this study investigated TrA function in relation to frequency of ETAP experienced by the physicallyactive population to determine if TrA contraction and strength isgreater in those who are asymptomatic of ETAP in comparison tothose who are symptomatic of ETAP.