A large proportion of persons who have had COVID-19 have reported persisted symptoms as fatigue and dyspnea months post infection which affect activities of daily living.

The aim of the study is to examine the feasibility and safety of a concentrated rehabilitation program with a mobile application follow-up for persons with persistent symptoms post COVID-19 infection. We will examine recruitment availability, adherence to the program, goal achievement, and resources requirements.

Methods: A feasibility study with one group pre-post test design with 10-20 persons between 18-67 years, with persistent symptoms post COVID-19 will be included. The intervention is 3+ 1-2 days concentrated rehabilitation with a mobile application follow-up for 3 months.

Following assessments wil be used: Cardiopulmonary exercise testing, lung function, functional performance tests, questionnaires regarding dyspnea, fatigue, anxiety, depression, work-status, health status, sleep behavior, physical activity level.

Demographic data before and after the intervention will be presented. Focus group interview will be done with the participants. The interview will be analysed using systematic text condensation.

In March 2020, the World Health Organization (WHO) declared the COVID-19 outbreak to be a pandemic, and a year later more than 120 000 000 people are confirmed with the disease. The disease has caused more than 2 700 000 deaths globally. Norway has a low mortality rate compared to rest of the world. However, a large proportion (10-33%) of the patients worldwide have reported persistent symptoms, such as dyspnea, reduced exercise capacity, loss of taste/smell and fatigue months after the infection. Persistent symptoms are also found in younger populations and in persons with an initially mild disease.

The intervention will take place at "Helse i Hardanger" (HiH)(Health center in Hardanger, Norway). The participants will stay for a 3 -day rehabilitation intervention, if needed, another 1 or 2-day stay will be offered about a month later. The concentrated treatment will be given by an interdisciplinary team, including doctors, physiotherapists, nutritionists, pharmacists, psychologists/psychiatrists, and nurses. The intervention is an individualized group treatment based on behavioural change.

Inclusion Criteria:

• persistent symptoms minimum 2 months post COVID-19 infection
• reduced exercise capacity level
• symptoms of dyspnea and/or fatigue

Exclusion Criteria:

• diseases where exercise is contraindicated (e.g. unstable angina pectoris)
• drug abuse, severe mental illness where treatment in groups are contraindicated.

In accordance with the approvals granted for this study by The Regional Committee on Medical Research Ethics and The Norwegian Data Inspectorate, the data files are stored securely and in accordance with the Norwegian Law of Privacy Protection. A subset of the data file with anonymized data can be made available to interested researchers upon reasonable request to Bente Frisk providing Norwegian privacy legislation and General Data Protection Regulation (GDPR) are respected, and that permission is granted from The Norwegian Data Inspectorate and the data protection officer Western Norway University og Applied Sciences