Participants will agree with their therapist on an exercise plan (endurance and resistance training) that will be made available through the studies mobile app. Frequency and duration of endurance and strength training shall be prescribed in accordance with exercise guidelines for persons with MS. However, they can be adjusted according to participants prior physical activity level and their time for exercise during the week.

This questionnaire contains 17 items that form a physical and cognitive subscale. The total score ranges from zero to a maximum of 68 points (maximum fatigue). The cut-off value for the presence of fatigue is above 32.

German version of the Center for Epidemiologic Studies Depression Scale, 20 item questionnaire. Each item is rated on a 4-point Likert scale. Answers are scored from 0 to 3. The scores for all items are added up to receive the total score. The total score ranges from 0 to 60 with higher scores representing higher levels of depression.

12-item questionnaire measuring self reported walking ability. Each item is answered on a 5-point Likert scale. Answers are scored from 1 to 5. The scores for all items are added up to receive a total score. The total score ranges from 12 to 60 with higher scores representing higher levels of depression. As a last step the total score is transformed into the walk12-score ranging from 0 to 100 ((total score -12)/48 x 100 = walk12-score).

An disease-specific questionnaire that measures quality of life and limitations due tu multiple sclerosis on two subscales (physical impact of MS, 20 items; psychological impact of MS, 9 items).Scores for both scales are generated by summing individual item scores and transforming the sum to a 0-100 scale. Higher scores represent worse health.

The task is to walk a 25foot distance as fast as possible. This test measures the functionality of the lower extremity and the walking speed.

The 2MWT measures walking endurance. It measures walking distance over 2 minutes. The subject is asked to walk as far as possible in 2 minutes.

The SSK-Scale measures self-rated physical activity-related and sports-related self-concordance. It contains 12 items which are assigned to 4 subscales: intrinsic, identified, introjected and extrinsic Motivation. An overall score can be calculated based on these four subscales (minimal score = -10, maximal Score = +10). To receive the overall score the scores of the subscales for introjected and extrinsic motivation will be subtracted from the sum of the identified and intrinsic motivation subscales. A high total score suggest a high level of physical activity-related and sports-related self-concordance.

44-item questionnaire that measures physical activity-related health competence. The physical activity related health competence consists of three subcompetencies: movement competence (20 items; min = 0, max = 17.6), control competence (10 items; min = 0, max = 10.8), PA-related self-regulation competence (14 items; min = 0, max = 14.8).

This is a questionnaire to estimate the satisfaction of the three basic psychological needs based on self-determination theory during sports- and exercise related activities. It consists of 11 items which are assigned to 3 scales (one for each psychological need). Higher values on the scales indicate a higher needs satisfaction.

The module usability and usefulness of the meCue 2.0 questionnaire was used. The module contains 3 items on usability and 3 items on usefulness that are answered on a 7-point Likert scale (scored from 1 to 7). In order two receive a score for usability and a score for usefulness, the mean is calculated for the items of each area.

Questionnaire including the Net Promoter Score and 45 self-developed items. Self-developed items covered willingness to pay, goal attainment, effects on physical function and wellbeing, adequacy of exercise prescription, evaluation of communication within the program, learning modules, App functions and activity trackers.