Most youth with MS experience symptoms such as depression and fatigue. In addition, cognitive issues, especially with attention and memory occur frequently. However, little is known about interventions that might work to improve these symptoms. In other work, the investigators have shown that higher levels of physical activity are associated with lower levels of depression and fatigue. Importantly, sleep problems are frequently encountered in youth with MS, and were seen in 60% of surveyed youth with MS in the investigators preliminary work. Modifiable lifestyle factors such as sleep and physical activity (PA) may play a key role in ameliorating common symptoms in pediatric MS. However, sleep has not been objectively described in pediatric MS, and the relationship between PA and sleep is poorly understood. This study aims to address these gaps.

Inclusion Criteria:

1. Children ages 10 to 17 years, 11 months;
2. MS diagnosis following standard definitions (IPMSSG);
3. Healthy controls will include any child without a history of disease or disability

Exclusion Criteria:

1. Inability to communicate or understand English;
2. Those within 30 days of a relapse;
3. Children who exhibit severe respiratory problems at baseline (e.g. use of tracheotomy)

There will be a total of 60 participants in this study. The study population consists of both patient participants (pediatric multiple sclerosis patients) and non-patient participants (healthy volunteers).