Optimal trunk control relies on somatosensory, motor and musculoskeletal integrity, which is often damaged in multiple sclerosis (MS). Researches on postural control in people with MS (PwMS) have revealed that reduced somatosensory conduction may adversely affect some functions. PwMS have increased postural sway in upright posture than healthy people. They move closer and slower when reaching out or taking a step. Trunk controls are weak and postural responses are delayed. The activation of core muscles is very important for an effective trunk control. Because the core region is considered a kinetic link that facilitates the transfer of torque and angular momentum between the upper and lower extremities during body movements. The decrease in core stability affects both trunk control and the quality of limb movements due to the kinetic chain in the body. There are a limited number of studies in the literature showing that core stability is reduced in PwMS. Our knowledge about the effects of this reduction on function in PwMS is very limited.

The aim of this study is to evaluate core strength and endurance and determine its effect on postural control, knee muscle strength, physical capacity and fatigue parameters in individuals with MS. Also relationship between these parameters will investigate.

Inclusion Criteria:

• Being diagnosed with MS according to McDonald's criteria
• Disability level less than 6 according to EDSS (Expanded Disability Status Scale) score
• No attacks during the last 3 months
• Being an ambulatory
• Volunteering to participate in the study

Exclusion Criteria:

• Having orthopedic, neurological, psychological, etc. diseases that accompany MS and may affect treatment outcomes
• Doing regular sports
• Being involved in another physiotherapy and rehabilitation program related to MS

People with MS followed in the Neurology Department of Bakirkoy Prof. Dr. Mazhar Osman Education and Research Hospital for Psychiatric and Neurological Diseases will be included.