Table 1.

Questionnaire items used to examine the participants’ perceptions of the machine learning-based lower-limb exercise training system.

Perception	Questionnaire item
Perceived effects of the system:
On exercise performance	Using the system would improve my performance in lower-limb exercises
On knee health	Using the system would increase my chances of improving knee health
On exercise adherence	The system would promote my adherence to lower-limb exercises
Perceived ease of use of the system	Learning to use the system would be easy for me
Attitude toward:
Video demonstration of lower-limb exercises	It is a good idea that the system has lower-limb exercise videos instructed by a physical therapist
Real-time movement feedback	It is a good idea that the system has real-time movement feedback on performing lower-limb exercises
Tracking of exercise progress	It is a good idea that the system tracks my exercise progress
Intention to use the system	Assuming that I have access to the system, I intend to use it