TONEFITreha: Proof of Concept and Usability Study.

Participants will be asked to rate the perceived usability based on the System Usability Scale (SUS). SUS assesses perceived effectiveness (can users successfully achieve their objectives), information quality (how much effort and resource is expended in achieving those objectives) and general satisfaction (was the experience satisfactory). The SUS hast 10 items that can be rated on a 5-point likert scale. The items will be scored as follows:

• For odd-numbered items, user response-1. For even-numbered items 5-user response. This scales all values from 0 to 4 (with four being the most positive response). Ref: Jeff Sauro, measuring usability
• Add up the converted responses for each user and multiply that total by 2.5 (to convert the range of possible values from 0 to 100 instead of from 0 to 40).
• single missing values are replaced with a neutral 3. Normative values will be used to grade the achieved median score (A through D, with D being least acceptable grade).

Each participant will have a list of tasks to be completed per session. Amount of additional assistance following the introduction (after three supervised sessions), will be counted as outcome. E.g. additional verbal cues or practical assistance.

Each participant will have a list of tasks to be completed per session. mean completion rate/mean task time = completion rate efficiency [%/s]; e.g. 80% completed all tasks within an average of 360 seconds.

Task time: mean time taken before training was started [s].

Each participant will have a list of tasks to be completed per session. mean goal achievement/mean task time = Goal achievement efficiency [%/s]; e.g. 43% completed in 360 seconds Mean goal achievement: Mean extent to which the tasks were completed [%], e.g. 3 out of 7 tasks completed correctly = 43%.

Standardised clinical assessment often employed as part of routine assessments will be used. The 10 Meter Walk Test (10MWT) is a performance measure used to assess walking speed in meters per second over a short distance. It can be employed to determine functional mobility, gait, and vestibular function.

A second standardised clinical assessment often employed as part of routine assessments will be used. The 6 Minute Walk Test (6MWT) is a sub-maximal exercise test used to assess aerobic capacity and endurance.

Cardiopulmonary response will be measured using a breath-by-breath cardiorespiratory monitoring system (MetaMax 3B, Cortex Biophysik, Leipzig, Germany) and a receiver board (HRMI, Sparkfun, Boulder, USA). During 10 meter walk test and a 6-minute walk test, oxygen uptake (VO2) and carbon dioxide output (VCO2) will be recorded and reported and VCO2/VO2 relationship.

During 10 meter walk test and a 6-minute walk test, heart rate (HR) will be recorded in both conditions (with and without belt). HR will be recorded over a rate belt (T31, Polar Electro, Kempele, Finland).

The amount of experience with walking exercise (qualitative, verbal description or as hours/week, if applicable),

• attitude towards technology and the use of sensors (visual analogue scale, VAS, 0 to 100mm, where 0 stands for 'negative attitude' and 100 for 'positive attitude'),

Age in years.

Weight [kg] and height [m] in BMI [kg/m^2]

Profession (qualitative description)

For attrition, the number of participants lost during the intervention was recorded. For adherence, participants' engagement with the intervention will be assessed.

Adherence will be calculated as the number of completed training sessions as a percentage of the maximal possible training sessions.

Training duration and intensity will be derived from the smartphone interface.