Effectiveness of a Smartphone Chatbot to Improve Exercise Adherence in Older Adults (EXEBOT)

Participants will receive a 12-week home-based multicomponent exercise program delivered through a Telegram-based chatbot. The program includes three exercise sessions per week consisting of strength, balance, flexibility, and walking exercises with a predefined progression. The chatbot provides exercise prescriptions, instructional videos, reminders, monitoring of exercise completion, scheduling adjustments, and automated feedback to support adherence.

A 12-week home-based multicomponent exercise program delivered through a Telegram-based chatbot. The program includes strength, balance, flexibility, and walking exercises performed three times per week. The chatbot provides exercise prescriptions, instructional videos, automated reminders, adherence monitoring, scheduling adjustments, and feedback to support exercise participation.

• Telegram-Based Exercise Chatbot

Participants will receive a 12-week home-based multicomponent exercise program in a printed booklet. The program includes three exercise sessions per week consisting of strength, balance, flexibility, and walking exercises with a predefined progression. Participants will also receive a paper calendar to record exercise completion. No chatbot-based reminders, monitoring, or automated feedback will be provided. Participants will receive the same exercise content, dosage, and progression as the experimental group.

A 12-week home-based multicomponent exercise program delivered in a printed booklet. The program includes strength, balance, flexibility, and walking exercises performed three times per week with the same content and progression as the experimental intervention. Participants record exercise completion using a paper calendar and do not receive chatbot-based reminders, monitoring, or feedback.

Exercise adherence will be measured as the percentage of the 36 prescribed exercise sessions completed during the 12-week intervention period. Adherence will be calculated from participant exercise records and expressed as a continuous percentage value.

Number and proportion of participants completing at least 80% of the prescribed exercise sessions during the intervention period.

Physical function assessed using the Short Physical Performance Battery. Scores range from 0 to 12, with higher scores indicating better physical performance.

Mobility assessed as the time required to stand up from a chair, walk 3 meters, turn, return, and sit down.

Physical activity will be assessed using the International Physical Activity Questionnaire for the Elderly (IPAQ-E). Physical activity is quantified as MET-minutes per week (MET-min/week), calculated from the frequency and duration of walking, moderate-intensity, and vigorous-intensity physical activities performed during the previous week. The questionnaire does not have a predefined minimum or maximum score, as results are reported as a continuous measure of energy expenditure. A practical minimum score is 0 MET-min/week, while no upper limit is defined. Higher scores indicate higher levels of physical activity and therefore a better outcome.

Participant satisfaction with the intervention will be assessed using the Client Satisfaction Questionnaire-8 (CSQ-8). The CSQ-8 consists of 8 items, each scored on a 4-point Likert scale. Total scores range from 8 to 32 points, with higher scores indicating greater satisfaction with the intervention and therefore a better outcome.

Perceived usability of the chatbot will be assessed using the System Usability Scale (SUS). The SUS is a 10-item questionnaire with responses scored on a 5-point Likert scale. Total scores range from 0 to 100, with higher scores indicating better perceived usability of the chatbot and therefore a better outcome. This outcome will be assessed only in participants allocated to the chatbot intervention group.