Therefore, an appropriate exercise program should be able to provide muscular support , minimizing the risk of disability by recovering the functionality of the spine ( McFeely ; GRACEY , 2006). For this purpose it is recommended to strengthen the abdominal muscles , lower back and lower limbs ( HANDA et al . , 2000; CALMELS et al . , 2004; Lidder ; BAXTER ; GRACEY , 2004; HAYDEN et al . , 2005; McFeely ; GRACEY , 2006; RODACKI et al . , 2008) .