Introduction: Home-based rehabilitation has the potential to reduce healthcare costs. However, due to less supervision in the home situation, it is possible that movements are made incorrectly. Therefore it is important to gain insight in which movements are made with a home-based rehabilitation system and what effects instructions could have on these movements. The current study investigated these movements made by the Rehabilitation Gaming System (RGS) app, this app uses augmented reality to provoke upper limb movements.

Methods: 16 healthy elderly and 16 stroke survivors participate in this study. Each participant was invited to the rehabilitation clinic for a one time measurement of 1.5 hours. During this measurement, four therapy exercises and four games on the RGS-app are performed. Each game should provoke a similar movement as one of the therapy exercises. Participants start with performing the therapy exercises for two minutes each. Thereafter they receive a video instruction on how to perform one of the games of the RGS-app, and they will play this game for 2 minutes. Thereafter the group is randomized into two conditions. The first group receives the same video instruction, while the second group receives a personalized live instruction based on the first two minutes of playing. After the new instruction, participants will play the game for two minutes again. This is repeated for all four games. Both the order of the therapy exercises and RGS-app games are randomized. During the study, participants wear Inertial Measurement Units (IMU's).

Inclusion Criteria stroke survivors:

• People who suffered from a stroke at least 2 months ago.
• Smartphone users
• Mild to moderate upper limb impairment (Medical Research Council Scale for Muscle Strength (MRC) ≥ 2)

Exclusion Criteria stroke survivors:

• Severe cognitive impairment
• Visual impairments (which cannot be corrected with glasses)
• Upper limb impairments not caused by the stroke

Inclusion Criteria healthy elderly:

• 60 years or older
• Smartphone users

Exclusion Criteria healthy elderly:

• Visual impairments (which cannot be corrected with glasses)
• Upper limb impairments which can affect smartphone use

Stroke survivors will be recruited through a Rehabilitation physician at the Sint Maartenskliniek and if needed through social media.

Healthy elderly will be recruited using social media.