colleagues observed that in those who regularly experience ETAP the most common locations for pain is the left and right lumbarregions of the torso and this location is consistent with pain fromthe intercostal nerves, which also service the parietal peritoneum.ETAP is regularly provoked when participating in activities thathave a significant amount of force transmission through the trunk,for example running and horse riding, and appears less commonly in cycling.During activities involving large dis placements of the abdomen (running/horse riding) or rotation (swimming)it is thought that there is excessive movement of the abdominal contents, which stresses the surrounding somatic anatomical structures.The local stabilising muscles of the spine, including transversus abdominis (TrA), internal obliques, lumbar multifidus,quadratus lumborum, pelvic floor muscles and the diaphragm,are involved in providing protection of the spinal column whilestationary and during functional movements.Their role in providing protection against posterior trunk musculoskeletal pain has previously been established, with Hodges and colleagues repor-ting evidence that a loss or delay of feed-forward activation of TrAis associated with chronic and recurrent low back pain.Therole of these muscles in controlling the more anterior trunk painassociated with ETAP has not been established.