This study evaluates the effects of a 10-week inspiratory muscle training on the outcomes of respiratory muscle strength, fatigue, activity participation, and respiratory infection rates in persons with advanced Multiple Sclerosis (MS). Participants will perform daily exercise using the Threshold Inspiratory Muscle Trainer (IMT) device during the training period. The study will assess whether the participants improve after the training, and whether the effects can be maintained after the training ends.

People with advanced multiple sclerosis (MS) often experience impairments in strength and endurance in the muscles of respiration. This can cause increased difficulty with breathing which may lead to increased respiratory infection. People with weak respiratory muscles may need to use more effort for breathing and this can be tiring and limiting a person's ability to participate in activities. Complications from breathing problems, such as pneumonia, are the most frequent reason for critical illness and intensive care in people with MS, particularly as the disease progresses.

Exercises of the respiratory muscles have the potential to improve breathing in people with MS. The goal of this study is to examine the effects of a 10-week respiratory muscle exercise program on respiratory muscle strength, fatigue, activity level, and respiratory infection rates in people with advanced MS. The study will assess whether the participants improve after the training, and whether the effects can be maintained after the training ends.

The study will invite 40 people with advanced MS to participate in a 10-week exercise program to strengthen respiratory muscles. Participants will use a device that is easy to use and provides a resistance while inhaling. Participants will perform the exercises after they receive the instruction from researchers. The progression of exercises will be tailored to each individual's tolerance to the exercise. The study will measure participants' respiratory muscle strength, perceived fatigue, participation in daily recreational activities such as coffee time, and respiratory infection rates to evaluate the effects of the program. The measurements will be done upon enrollment into the study at the baseline, after 10-week no training baseline period before the intervention, mid-point during the 10-week training, at the completion of the 10-week training, at 4 weeks and at 8 weeks after the training ends. The study will evaluate if participants improve after the training, and if the improvements can be maintained for up to 8 weeks after the training.

Outcomes from this research will help to better understand effective treatments for breathing problems in people with advanced MS. The study will be able to inform clinicians and researchers about effective protocols for respiratory muscle training in advanced MS. These results will contribute to long-term research goals, including reducing complications from respiratory problems, delaying disability associated with MS, and improving function and quality of life in people with advanced MS.

Inclusion Criteria:

• Residents of The Boston Home
• Diagnosis of multiple sclerosis by a physician
• Expanded Disability Status Scale >6.5
• Able to follow instructions in English

Exclusion Criteria:

• Hospitalization for exacerbation of MS within the previous 2 months
• Unstable heart, lung, or other physical conditions
• Current smoker
• Oral temperature greater than 100 degrees Fahrenheit
• Acute illness, such as infection, inflammation, ongoing chest pain, or short of breath with light activities
• Current neurological diseases other than MS