The aim of this study was to describe physiotherapeutic interventions during post-acute inpatient rehabilitation of chronic critically ill patients with intensive-care-unitacquired muscle weakness, and to determine the relationship of such interventions with patients' recovery of walking ability. The study included 150 patients with chronic critical illness and acquired muscle weakness, and documented what interventions physiotherapists applied during rehabilitation and how well patients regained walking function. The most frequent interventions in the first 2 weeks of rehabilitation in patients who regained walking ability were: practicing walking, sit-to-stand training, and balance training while sitting. In those who did not regain walking ability the most frequent interventions were: passive-assistive movements, sit-to-stand training, and balance training while sitting. The time spent walking in physiotherapy was correlated with walking function. Physiotherapy in the rehabilitation of chronically critically ill patients with intensive-care-unit-acquired muscle weakness may be correlated with achieving independent walking. Objectives: To describe physiotherapeutic interventions used in the post-acute inpatient rehabilitation of chronic critically ill patients with intensive-careunit-acquired muscle weakness, and to determine the influence of such interventions on patients' ability to walk. Methods: Chronic critically ill patients with intensive-care-unit-acquired muscle weakness who were in post-acute and rehabilitation units were included in a cohort study. During post-acute rehabilitation, the patients' functional status at baseline, all daily physiotherapeutic interventions, and ability to walk were documented. Results: A total of 150 patients were investigated. In patients who regained walking ability, the most frequent interventions in the first 2 weeks of postacute rehabilitation were practicing walking, sit-tostand training, and balance training while sitting (total time per week: 48.03 (standard deviation (SD) 41.10), 20.13 (SD 21.12), and 12.37 (SD 26.95) min, respectively). The most frequent interventions in those who did not regain walking ability were passive-assistive movements, sit-to-stand training, and balance training while sitting (total time per week: 15.29 (SD 22.93), 15.15 (SD 22.75), and 14.85 (SD 16.99) min, respectively). The time spent walking increased the chance of regaining walking ability (adjusted hazard ratio = 1.017 per min walking, p < 0.0001). Conclusion: These results suggest that physiotherapy interventions in the rehabilitation of chronic critically ill patients with intensive-care-unit-acquired muscle weakness may stimulate walking function.