The purpose of the present investigation is to determine whether MS patients can tolerate and benefit from heavy progressive resistance training. A second purpose is to determine both neural and muscle morphological adaptations to heavy progressive resistance training.

Multiple sclerosis (MS) patients are characterized by reduced muscle strength and functional capacity. For MS patients, improvements in muscle strength and thereby functional capacity, would have the potential to make both the daily living easier and to extend the time living independently. Attempts to improve muscle strength and function include the application of physical training, although the general advice to MS patients for many years has been to avoid participation in physical training. It has now been demonstrated that endurance training at low to moderate intensity is well tolerated by MS patients, but it only induces modest improvements in both muscle strength and functional capacity. Heavy progressive resistance training (HPRT) has proven to be the most effective means to improve muscle strength and functional capacity during daily activities in healthy older people. However, the effects of HPRT have not been investigated in randomised control trials in MS patients.

Inclusion Criteria:

• Clinical diagnosis of Relapsing Remitting Multiple Sclerosis according to the McDonald criteria
• Expanded Disability Status Scale Score between 3,0-5,5
• Be able to walk at least 100m
• Be able to train twice a week at the University

Exclusion Criteria:

• Alcohol abuse, Alzheimer's and pacemaker
• Comorbidities like cardiovascular-, respiratory-, orthopaedic or metabolic diseases
• Having had an attack in a period of 8 weeks prior to the start of the intervention period
• Having an attack during the intervention period
• Pregnancy
• Systematic resistance training in a period of 3 months prior to the start of the intervention period.
• Training adherence of less than 85%.