Participants will attend two sessions per week for 6 weeks. Each session will involve 6-10 sets of 60 seconds of high intensity cycling followed by 60 seconds rest. Potential participants must have a clinical diagnosis of Mulitple Sclerosis for more than 3 months, an EDSS score of less than 2.5, aged 18-65, and had no more than one relapse in the last 2 years.