Using ultrasound to assess the thickness of the transversus abdominis in a sling exercise.

BMC Musculoskeletal Disorders

PubMedID: 26286595

Lükens J, Boström KJ, Puta C, Schulte TL, Wagner H. Using ultrasound to assess the thickness of the transversus abdominis in a sling exercise. BMC Musculoskelet Disord. 2015;16203.
BACKGROUND
Activation of the deep stabilizing trunk muscle transversus abdominis (TrA) is important for trunk stabilization and spine stability. Sling exercises are used for the activation of trunk muscles, therefore we determined the thickness of the TrA in a standardized sling exercise in comparison to rest and abdominal press. Furthermore we propose a standardized measurement method, which can be used to compare relative muscle thickness levels in different exercises.

METHODS
The main objective of the study was to assess and to compare the thickness of the TrA during different conditions; resting condition, sling exercise condition (non-voluntary contraction), and abdominal press condition (voluntary contraction) using a non-invasive ultrasound-based measurement method. Ultrasound measurement (USM; 8.9 MHz, B-mode) was employed to measure the thickness of the TrA in twenty healthy volunteers (13 m, 7 f), each one measured three times with breaks of 48 h. On each measurement day, the subjects were measured on three different conditions: resting condition (RC), sling condition (SC), and abdominal press condition (APC). The USM images were analyzed using a custom-made MatLab script, to determine the thickness of the TrA.

RESULTS
A two-way repeated-measurements ANOVA was performed with a significant effect of the factor condition [F(2,38)?=?47.82, p?
CONCLUSIONS
We showed that the investigated sling exercise can be used to significantly increase the TrA thickness, and that the TrA thickness was significantly different on the three conditions (RC, SC, APC) using the ultrasound-based method.