The goal of this clinical trial is to demonstrate the improvement of motor functions related symptoms in patients with MS and spasticity using Exopulse Mollii suit stimulation in Multiple Sclerosis patients with spasticity. The main questions it aims to answer are:

• to evaluate the short-term impact of EXOPULSE Mollii suit on balance in adult MS patients suffering from spasticity.
• to assess the effects of EXOPULSE Mollii suit on mobility, upper and lower limbs muscle tone, pain, fatigue and quality of life.

Participants will participate in:

• One baseline visit for inclusion during which the patient will undergo the first session (active or sham) along with evaluations (before and after the session)
• One visit after two weeks during which the patient will undergo the second session (active or sham) along with evaluations (before and after the session)
• One visit after two weeks of the second stimulation condition; the patients will undergo a third evaluation and receive the EXOPULSE Mollii Suit for the four-week open label phase and will use the suit at home for an active stimulation session every other day for four weeks.
• One visit at the end of the open label phase to perform the fourth and last evaluation and return the EXOPULSE Mollii suit.

Researchers will compare both Active and Sham groups to demonstrate the improvement of motor functions related symptoms in patients with MS and spasticity using Exopulse Mollii suit.

The study is a randomized crossover, sham-controlled, double-blind trial to demonstrate the improvement of motor functions and MS related symptoms following a single session of "active" versus "sham" EXOPULSE Mollii suit stimulation. in phase 1, the patient will receive two stimulations separated by a two-week washout period. The patients will be randomized to receive either active/sham or sham/active and both patients and investigators will be blinded to the order in which the stimulation will be given. A 2-week washout period should be enough to prevent a potential carry over effect. Two weeks after the end of phase 1, a second open label phase (phase 2) of this trial will be proposed to all patients where they will receive active stimulation every other day at home over four weeks (for a total of 14 sessions). This will help understand the long term effects of EXOPULSE Mollii suit stimulation on MS related symptoms.

Inclusion Criteria:

• Definite MS diagnosis according to the 2017 McDonald criteria since at least one month.
• Age between 18 and 75 years.
• Ability to walk freely or with the need of support (expanded disability status scale score (EDSS) < 7).
• Being free of relapses in the last three months.
• Being able to understand verbal instructions.
• Having spasticity with a score of at least 1+ on the MAS.
• Having a BBS score ≤46 associated in the literature with a risk of fall.

Exclusion Criteria:

• Being included in another research protocol during the study period.
• Inability to undergo medical monitor for the study purposes due to geographical or social reasons.
• Having a cardiac stimulator, a ventriculoperitoneal shunt, an intrathecal baclofen pump or other contraindications to using EXOPULSE Mollii suit.
• Being pregnant.
• Having a change in their pharmacological therapy in the last three months.
• Suffering from other somatic or neuropsychiatric diagnoses (e.g., arrhythmias, uncontrolled epilepsy, diseases causing osteoarticular and muscular pain).
• Having a body mass index above 35 kg/m^2.
• In case of the introduction of a medical device other than EXOPULSE Mollii suit during the study period.
• Patients under juridical protection.
• Prisoners.