Pilates exercise and resistance training both increase deep muscle thickness of the internal obliques [IO] in female exercisers, but Pilates seems to be more effective for conditioning the transversus abdominis [TA], according a small study involving both experienced and novice exercisers. Researchers from Dankook University in Cheonan, South Korea, conducted the study to determine whether Pilates or resistance training was more effective for lumbar stabilization.

Study participants were aged 22–27. There were 10 Pilates instructors, 10 resistance training instructors and 10 inactive participants. Investigators compared muscle activation during four exercises: abdominal drawing-in, bridging, roll-up and one-leg raise. Surface muscle activation was measured with electromyography, and deep muscle activation was measured by ultrasound imaging.

Pilates and resistance training instructors had more activation of deep muscles such as the IO and the TA than control group members did. All participants had similar activation of surface muscles. Researchers concluded that both Pilates and resistance training are effective for increasing deep abdominal muscle thickness.

The study was published in the Journal of Exercise Rehabilitation (2015; 11 [3], 161-68).