Multiple sclerosis (MS) is a chronic, progressive and unpredictable disease of the central nervous system. In MS, various loss of strength, balance and gait disturbances arise in the central nervous system due to sensory and/or motor neuron degeneration. These disorders lead to limitations in individual activities and participation.

Fatigue is as reported one of the most common first three symptoms among patients with MS and affects up to 80% of the patients. Fatigue is defined as the lack of physical and/or mental energy. Sometimes fatigue can reduce the quality of life by leaving other disorders behind. The most important effect of fatigue is that individuals reduce their physical activity levels. This can lead to the inactivity-related secondary problems being added to the findings of the disease. So the physical capacities of individuals may gradually decrease.

In the literature, there are many studies showing that the level of physical activity of individuals with MS is lower than in healthy individuals. When the investigators analyze the studies that investigate the relation between fatigue and physical activity levels, it is seen that there is the single study about this subject in the literature.

As a result, additional studies are needed to investigate the level of physical activity and the factors affecting it in individuals with MS. Therefore, the investigators planned this study to investigate the relationship between fatigue and physical activity levels in patients with MS.

According to sample size calculation 37 diagnosed Multiple Sclerosis patients and 37 healthy individuals will be included.The demographic characteristics of the participants initially will be taken and Expanded Disability Status Scale score of those of MS will be recorded. Then, fatigue severity and perception, physical activity level, balance, peripheral muscle strength, functional mobility, functional exercise capacity will be evaluated. Primary outcomes are fatigue and physical activity level; secondary outcomes are balance, peripheral muscle strength, functional mobility, functional exercise capacity.

Inclusion Criteria:

• 18-65 years of age
• Having a diagnosis of "Multiple Sclerosis" by a specialist physician
• Relapse free in the last 3 mounts
• Having an ambulatory status (Expanded Disability Status Scale score ≤ 6 )
• No diagnosis of depression

Exclusion Criteria:

• Any cardiovascular, orthopedic, visual, hearing and perception problems that may affect the results of the research

Power analysis was performed using "G * Powerversion3.1 program" in order to determine the minimum number of subjects to be taken into operation. Accordingly, the number of participants in the study group (n) = 37 (α: 0.05, for power 80%) and in the control group (n) = 37).

There is not a plan to make individual participant data but when the statistical analyses of all data are made, all results will be shared