Changes in physical function, pain and quality of life following app-based exercise intervention: A single-arm interventional cohort study

Background The prevalence of insufficient physical activity among adults has increased globally, driving the demand for remote exercise support. The KOJI AWARENESS (KA) program enables self-assessment and provides corrective exercise routines without professional supervision. In this study, we hypothesized that an 8-week KA telemedicine program would be associated with changes in physical function, pain, fatigue, and EuroQol-5D-5L (EQ-5D-5L), and we tested this hypothesis accordingly. Methods This study involved 60 healthy adults aged 20–70 years, from April 2024 to February 2025. This was a single-arm, interventional cohort study without a control group. All participants completed an 8-week individually prescribed exercise program based on their application-based self-screening test scores (KA scores). The pain, KA scores, Brief Fatigue Inventory (BFI), and EQ-5D-5L were assessed before and after exercise. Results The KA scores increased at 8 weeks (before vs. after 8 weeks, p < 0.001, r_rb = 0.94), whereas the pain scores decreased significantly (before vs. after 8 weeks, p < 0.05, r_rb = -0.51). The BFI score significantly decreased after 8 weeks, (before vs. after 8 weeks, p < 0.05, r_rb = -0.42), but the EQ-5D-5L score showed no significant change. Conclusion Changes in physical function and BFI scores were observed over the 8-week study period; however, these changes did not reach a minimum clinically important difference. Furthermore, no significant differences were observed in EQ-5D-5L scores, suggesting a possible ceiling effect. The results should be interpreted with caution because of the lack of a control group and inherent biases.