サルコペニアにおける筋力改善を目的としたデジタル治療機器の安全性と有効性の評価（Sarc-DTx）

Participants perform personalized resistance exercises using a digital therapeutic device (mobile application) at home for 12 weeks, with sessions conducted at least 3 times per week, 50 minutes per session (≥150 minutes/week). The program includes exercise automatic intensity adjustment, exercise recording/analysis, and physician monitoring

Experimental group (exoDTx): After baseline on-site training, participants perform personalized resistance exercises at home using a mobile app ≥3 times/week, 50 min/session, for 12 weeks (≥150 min/week). The program provides grip strength-based automatic intensity adjustment, exercise recording, feedback, and physician monitoring.

Delivery: Nonpharmacological, non-invasive, home-based exercise program. The experimental group uses a mobile app; the control group uses educational materials.

Initial instruction occurs on-site. Visits & Monitoring: Screening/Baseline (week 0), In-treatment (weeks 4, 8), Post-treatment (week 12), and Follow-up (week 24).

No mobile application is used. Participants perform the same type of exercise using QR code-based educational materials, self-regulating their exercise time, at least 3 times per week, 50 minutes per session, for a total of 12 weeks, with frequency and duration identical to the experimental group.

Control group (Self-exercise): No app is used. Participants perform the same exercise guided by QR code-based educational materials, ≥3 times/week, 50min/session, for 12 weeks, maintaining exercise logs without automatic adjustment or remote monitoring.

Delivery: Non-pharmacological, non-invasive, homebased exercise program. The experimental group uses a mobile app; the control group uses educational materials. Initial instruction occurs on-site. Visits & Monitoring: Screening/Baseline (week 0), In-treatment (weeks 4, 8), Post-treatment (week 12), and Follow-up (week 24).

Between-group comparison of mean change in knee extensor strength measured by lower extremity dynamometer.

To evaluate longitudinal changes in knee extensor muscle strength at weeks 4, 8, and 24 compared with baseline using an lower extremity dynamometer.

To evaluate changes in muscle and fat mass measured by dual-energy x-ray absorptiometry(DXA) or bioelectrical impedance analysis (BIA) after 12 weeks of intervention.

To assess changes in muscle strength based on standardized MMT grading (0-5 scale) after 12 weeks of intervention..

To assess longitudinal changes in handgrip strength measured by hand dynamometer at weeks 4, 8, 12, and 24.

To assess longitudinal changes in calf circumference measured at the maximum girth of the dominant or less-affected lower leg at weeks 4, 8, 12, and 24.

To quantify changes in muscle fatigue characteristics derived from surface electromyography (EMG) during resistance exercises.

To examine motor recovery and coordination improvements using the Fugl-Meyer Assessment in participants with CNS-related sarcopenia.

To assess changes in lower limb functional strength and endurance measured by the number of sit-to-stand repetitions completed in 30 seconds after 12 weeks of intervention.

To assess improvement in walking independence level using the Functional Ambulation Category (0-5 scale).

To evaluate dynamic and static balance performance using BBS score and TUG test time.

To assess lower extremity function using SPPB, including 5-time chair stand, 6-meter gait speed, and balance tests.

SPPB - 5-time chair stand (time) 6-meter gait speed (SPPB gait speed) SPPB balance - score SPPB balance - time in seconds

To assess changes in self-reported sarcopenia risk using the full Strength, Assistance with walking, Rise from a chair, Climb stairs, and Falls questionnaire. The SARC-F consists of 5 items, each scored from 0 to 2, resulting in a total score ranging from 0 to 10, with higher scores indicating worse sarcopenia severity and greater functional limitation.

To measure sarcopenia-specific quality of life changes using Sarcopenia Quality of Life total score and domain subscores.

Sarcopenia Quality of Life contains 55 items generating a total score from 0 to 100, with higher scores indicating better quality of life.

To assess changes in self-reported health-related quality of life using the full EuroQol Five-Dimension Five-Level (EQ-5D-5L) questionnaire. The EQ-5D-5L consists of 5 items, each scored from 1 to 5, resulting in a total score ranging from 5 to 25, with lower scores indicating better health-related quality of life and higher scores indicating greater health impairment.

To evaluate participants' confidence in independently performing prescribed home-based exercises.

To assess user satisfaction and perceived usability of the exoDTx digital therapeutic application using SUS.