[Subjects] Thirty adult subjects with chronic back pain participated,
with 10 adults being assigned to each of 3 exercise groups: general physical therapy (PT), lumbar stability
using sling exercises (Sling Ex), and sling exercise plus push-ups (Sling Ex+PU). Each group trained for 30 minutes
3 times a week for 6 weeks. The Oswestry Disability Index (ODI), surface electromyographic (sEMG) activity of the
lumbar muscles, and cross-sectional area of the multifidus muscle on computed tomography (CT) were evaluated
before and at 2, 4, and 6 weeks of therapy