Physical Activity Intervention for MPS

Adults with Mucopolysaccharidosis will be eligible to participate in the study if they meet the following inclusion criteria: * Diagnosed with any type of Mucopolysaccharidosis. * Aged ≥ 18 years old. * Lives in the United Kingdom. * Deemed safe to participate by a clinician (for participatory workshops). Exclusion criteria for all participants will be as follows: * Incapacity to provide informed consent. * A level of intellectual disability that would prevent the individual from making a meaningful contribution to the focus groups or workshops. * Unable to communicate in English to a sufficient level to permit engagement in the study. The circumstances in which an individual may be deemed ineligible to take part in the participatory workshops based on the clinician's assessment are as follows: * Severe joint pain. * Neurological compromise. * Stage 4 heart failure or other condition resulting in breathlessness to a level they cannot participate. * Other clinical condition which dominates the clinical picture to the extent that it dominates the symptoms and influences the findings (e.g. stroke). Specialist stakeholders will be members of staff at NHS specialist centres for Mucopolysaccharidosis who are directly involved in healthcare provision to the target population. Lay specialist stakeholders will be individuals who have been involved in supporting adults with Mucopolysaccharidosis, such as family, friends, and members of staff and volunteers at the Society for Mucopolysaccharide Diseases.