Background: Core stabilization exercises are widely used to improve trunk stability, balance, and functional movement by enhancing the activation and endurance of deep trunk muscles such as the transversus abdominis (TrA). However, evidence comparing the effects of sling-based unstable surface training and mat-based stable surface training remains limited. Objects: To investigate the effects of mat based core stabilization exercises and sling based unstable surface core stabilization exercises on transversus abdominis thickness and core endurance. Methods: Forty-six healthy adults were randomly assigned to a mat exercise group (MEG, n=23) or a mat with sling exercise group (MSEG, n=23). Both groups performed 30-minute core stabilization exercises twice per week for four weeks. TrA thickness was measured using ultrasonography (SONON 300L), and core endurance was evaluated using the Bourban test for the anterior muscle chain. Results: Both groups showed significant increases in transversus abdominis thickness (MEG: P<.05; MSEG: P<.00) and core endurance (P<.00) after the intervention. However, no statistically significant differences were found between the two groups in post-intervention TrA thickness or Bourban test. Conclusion: Both mat based and sling based core stabilization exercises effectively enhanced TrA thickness and core endurance in healthy adults.

The purpose of this study was to verify the most effective spinal stabilization exercises program by comparing the activities of muscles contributing to spinal stabilization during four types of exercises using a sling and a mat. Twenty healthy males were recruited and each subjects performed four types of exercises. Exercise 1 was performed in a quadruped position with the subjects lifting the left arm and the opposite leg on the mat. Exercise 2 was performed in a prone position while holding a sling with the right hand and the left knee was fully extended while lifting the left arm and right leg. Exercise 3 was performed in quadruped position while holding a sling with one the right hand and lifting the opposite arm and leg. In exercise 4, subjects were instructed to maintain a balance push-up position while holding slings with both hands in 10 cm forward reaching with extended elbows. Electromyographic(EMG) activities were recorded from the multifidus, external oblique, internal oblique, abdominal rectus, and erector spinalis muscles during the exercises. The EMG amplitude of each muscle was normalized to the amplitude in the maximal voluntary isometric contraction (MVIC) of each muscle. Repeated ANOVA and Bonferroni's tests were used to compare the differences in the muscle activity according to the types of exercise. The EMG amplitudes of all the muscles were significantly different according to the types of exercises (p<.05). The highest EMG activities of each muscle was as follow; multifidus was 73.38%MVIC in exercise 3, the erector spinalis was 40.03%MVIC in exercise 3, the external oblique was 135.88%MVIC in exercise 4, the internal oblique was 128.60%MVIC in exercise 4, and the rectus abdominalis was 95.24%MVIC in Exercise 4. The types of exercises showed a significant difference in composition rate of EMG amplitudes of each muscle (p<.05). EMG composition rate of the multifidus was high in exercise 1 and 3. However, EMG composition rates of the external oblique, internal oblique, and the rectus abdominals were high in exercise 2 and 4. These results showed differences in EMG activities of muscles contributing to trunk stabilization during different therapeutic exercises. Therefore, the type of exercise should be carefully selected to effectively strengthen a specific trunk stabilizer.