Individually Prescribed In-Bed Exergaming Using Nintendo Ring Fit Adventure in Posttransplant Inpatients With Marked Functional Impairment After Intensive Care: Prospective Single-Arm Feasibility Study

Background Early rehabilitation is important after transplantation and critical illness, but profound weakness, fatigue, and motivational, psychological, and safety barriers may limit participation. Exergaming may facilitate rehabilitation, but the feasibility of full-body in-bed exergaming in this population remains unclear. Objective We evaluated the feasibility and observed safety of individually prescribed in-bed exergaming using Nintendo Ring Fit Adventure (NFA; Nintendo Co, Ltd) in posttransplant inpatients after intensive care unit (ICU) care. Methods This prospective, single-center, single-arm interventional feasibility study (October 2024-October 2025) enrolled 26 posttransplant adults with prior ICU care and Functional Ambulation Category (FAC) scores ≤3. Participants were referred after ward transfer by transplant-team advanced practice nurses, and the principal investigator confirmed eligibility based on prespecified inclusion and exclusion criteria. Ten individually prescribed, supervised in-bed NFA sessions, each scheduled for 30 minutes, including setup and operation, were planned alongside usual physical therapy. Data were obtained from medical records, standardized session logs, and prespecified clinical and questionnaire assessments. Outcomes included retention; session delivery, completion, and interruptions; exercise-item completion and interruptions; session-terminating adverse events; net exercise time; satisfaction; and exploratory strength, mobility, and health-related quality-of-life changes. Results Participants (mean age 53.0, SD 12.4 y; 14 men) included 23 liver and 3 bilateral lung transplant recipients. Mean ICU stay and mechanical ventilation duration were 24.3 (SD 11.0) days and 21.3 (SD 11.6) days, respectively; median baseline FAC and Medical Research Council Sum Score were 0.5 (IQR 0.0-1.0) and 38.0 (IQR 30.5-42.0), respectively. None had an FAC score above 2. Twenty completed the final assessment (20/26, 76.9%, 95% CI 57.9%-89%). Of 227 delivered sessions, 223 (98.2%, 95% CI 95.8%-100%) were completed. Of 2161 prescribed exercise items, 2072 (95.9%, 95% CI 93.4%-97.9%) were completed. No session-terminating adverse events were observed (0/227, 0%, 95% CI 0%-1.6%). Median within-participant net exercise time increased by 159.0 (IQR 35.5-296.3) seconds from sessions 1 to 10 (95% CI 81.0-284.0; Wilcoxon signed-rank test, P <.001). Friedman tests followed by Bonferroni-adjusted Wilcoxon signed-rank tests (2-sided α=.05) showed baseline-to-final median within-participant changes of 8.0 Medical Research Council Sum Score points (IQR 2.3-10.3; 95% CI 4.0-10.0, P =.004), 2.0 Intensive Care Unit Mobility Scale points (IQR 1.0-4.3; 95% CI 1.0-3.5, P <.001), and 15.0 EQ-VAS points (IQR 0.0-30.0; 95% CI 5.0-25.0, P =.009). Questionnaire responses were favorable. Conclusions Under therapist supervision, the individually prescribed in-bed NFA program showed favorable operational feasibility, with no session-terminating adverse events. By combining the accessibility of a commercial off-the-shelf exergame with individualized exercise prescription, the program extended bedside exergaming to posttransplant inpatients with substantial functional impairment after ICU care who had not achieved independent ambulation.