Effects of Two Corrective Protocols on Trunk Muscles in Females with Hyperlordosis; Williams vs McKenzie’s Protocol

Background & aim: One of the most common causes of back deformities is spinal curve change in the waist. Physical therapy is one of the most common methods for treatment of lordosise and back pain. In the field of corrective exercise, the comparison of Williams and McKenzie’s training findings are small and inconsistent. So, the purpose of this study was to compare the effects of 8 weeks of Williams and McKenzie’s corrective training on lumbar isometric strength in 15-18 year females with hyperlordosis. Methods: The study sample included 30 females with lumbar lordosis more than normal degrees (Hyperlordotic) in lumbar curve that randomly divided into Williams and McKenzie’s exercise groups. The lumbar lordosis was measured using a flexible ruler and isometric strength of trunk muscles were measured by using digital dynamometer. Data analyzed using independent and paired t-testes. Results: Results showed that both types of exercises led to significant increases in the strength of lumbar extensors, hip extensors and flexors and abdominal muscles strength and pain (p<0.001). However, any significant difference between the two types of exercises was not observed (p>0.05). Conclusions: The findings show that Williams and McKenzie corrective training can lead to significant improvement in lumbar lordosis and isometric strength; although there is no difference between these two types of exercise, thus, both protocols are suggested to relief and reduce back deformities.