The effect of hip abductor strengthening exercises on lower limb strength asymmetry and balance in women with multiple sclerosis: A randomized controlled clinical trial

Abstract

IntroductionPatients with multiple sclerosis tend to use and move their body segments in an unbalanced way, which causes asymmetry of muscle strength, especially in the lower limbs. Among these muscles, the hip abductor muscles play a more important role in stabilizing the pelvis and maintaining balance. The purpose of this research was to investigate the effect of hip abductors exercises on lower limb strength asymmetry and balance in people with multiple sclerosis. Materials & methodsIn this clinical trial with a pre-test-post-test design, 40 women with multiple sclerosis were purposefully selected and randomly divided into experimental and control groups. The experimental group performed hip abductor muscle strengthening exercises for 8 weeks and each session lasted 30 min. The control group did not receive any intervention and continued their daily activities. The strength of knee flexors and extensors, plantar-flexors and ankle dorsi-flexors was measured using a dynamometer. Static and dynamic balance was also evaluated using the stork test and timed get up and go test, respectively. ANCOVA test was used at a significance level of 0.05 to investigate the intergroup effects. ResultsThe results showed a significant decrease in the strength asymmetry of the knee extensor (P = 0.001) and knee flexor (P = 0.001) muscles in the experimental group. However, no significant difference was observed in the asymmetry of the strength of the ankle dorsi-flexor (P = 0.160) and plantar-flexor muscles (P = 0.698). The results also showed a significant improvement in static (P = 0.001) and dynamic balance (P = 0.001) in the experimental group. Discussions & conclusionsStrengthening the hip abductors improves the symmetry of the strength of the knee extensor and flexor muscles. It also improves the balance of people with multiple sclerosis.