Exercise is an important part of therapy guidelines in the rehabilitation of rare diseases (RDs) as Haemophilia and Myositis. The aim of this study is not to evaluate a new therapy intervention, but to evaluate the delivery of this intervention. In clinical practice, patients are usually instructed to perform an exercise program at home. Normally, a physiotherapist (PT) provides an instruction (paper-) sheet. In this study, the investigators evaluate the feasibility of an interactive tablet-based way of delivery. The exercise program is - as usual in physiotherapy - individually tailored by the PT.

Myositis and haemophilia belong with a prevalence rate of 0.4-17.3 of 100'000 and 2-12 of 100'000, respectively to the group of RDs. The fact that a RD affects only a small number of people, indicates that rehabilitation knowledge outside the specialised medical centers is rare. Thus, since many people with RD do not live nearby these institutions, they do not have direct acces to rehabilitation programmes. The University Hospital Zurich (USZ) offers medical treatment and Rehabilitation Support in such reference centers, among others for people with myositis (PWM) and for people with haemophilia (PWH).

Although these two diseases differ strongly in their underlying cause, affected persons are confronted with similar problems: PWM and PWH suffer from musculoskeletal problems and therefore, a physically active lifestyle is essential to maintain good health. Nevertheless, PWM and PWH were previously discouraged from participating in physical exercise. Consequently, both groups are less physically active, have a lower fitness level and a higher risk for comorbidities, compared to healthy people. Nowadays, the beneficial effects of exercise in PWH and in PWM are well accepted and there is evidence that PWH and PWM profit from physical exercise programs.

Despite the encouraging benefits of physical exercise in PWH and PWM, these may be challenged with more barriers to start and maintain an exercise program, compared to healthy persons, e.g. due to reduced accessibility of specialised physiotherapists.

Telerehabilitation (TR), a subfield of telemedicine, may help to overcome some of the barriers to exercise regularly and connect PWH/PWM with specialised physiotherapists. TR is defined as the provision of rehabilitation services from a distance using telecommunication technologies as the delivery medium. This approach may optimize the timing, intensity and sequencing of interventions and provide opportunities for individuals to receive rehabilitation in their own social and professional environments from disease-specialised caregivers. An additional advantage of TR is the possibility to implement different persuasive technologies such as personalisation, self-monitoring, tailoring, goal setting, comparison and conditioning through positive and negative reinforcement in the development of exercise programmes. These technologies help to make exercise programmes more enjoyable and, therefore, enhance patients' motivation to exercise regularly.

Furthermore, the importance of individual and social support has been emphasized in several reviews evaluating health behaviour change for example becoming more active. This kind of support can be integrated in the design of a TR program and it can further be enhanced by blending TR with face-to-face sessions. The so-called blended therapy is a promising approach combining the advantages from traditional rehabilitation and new technologies.

The aim of this study is to evaluate feasibility of a blended therapy approach, combining a tablet-based exercise program, called "Dividat Fit" with face-to-face therapy sessions for PWH and PWM.

Inclusion Criteria:

Diagnosis of mild Haemophilia or Myositis

• able to walk 20 meters without walking aids
• currently exercising less than one training session per week (training = vigorous activity)
• maintenance of a stable medical regimen for 4 weeks prior to initiation of study and considered to maintain a stable regimen for the course of the study
• signed informed consent to participate in the study

Exclusion Criteria:

• Clinically significant concomitant disease states (e.g., renal failure, hepatic dysfunction, severe cardiovascular and/or pulmonary disease, severe osteoporosis, pulmonary hypertension, pain syndrome, paresis)
• Contraindications to physical exercise for People with Haemophila: Factor-prophylaxis-regimen, inhibitor positive, less than 6 months after arthroplasty surgery, acute joint or muscle bleeding within the last 30 days for People With Myosites: acute exacerbation of inflammation
• Known or suspected non-compliance, drug or alcohol abuse,
• Inability to follow the procedures of the study, e.g. due to language problems, psychological disorders, dementia, etc. of the participant,
• Participation in another study with investigational drug within the 30 days preceding and during the present study
• Known pregnancy or breastfeeding