Purpose
Early mobilization of critically ill patients improves functional recovery, but is often hampered by tubes, drains, monitoring devices and muscular weakness. A mobile treadmill with bodyweight support facilitates early mobilization and may shorten recovery time to independent ambulation as compared to usual care physiotherapy alone.

Materials and methods
Single center RCT, comparing daily bodyweight supported treadmill training (BWSTT) with usual care physiotherapy, in patients who had been or were mechanically ventilated (≥48 h) with ≥MRC grade 2 quadriceps muscle strength. BWSTT consisted of daily treadmill training in addition to usual care physiotherapy (PT). Primary outcome was time to independent ambulation measured in days, using the Functional Ambulation Categories (FAC-score: 3). Secondary outcomes included hospital length of stay and serious adverse events.

Results
The median (IQR) time to independent ambulation was 6 (3 to 9) days in the BWSTT group (n = 19) compared to 11 (7 to 23) days in the usual care group (n = 21, p = 0.063). Hospital length of stay was significantly different in favour of the BWSTT group (p = 0.037). No serious adverse events occurred.

Interpretation
BWSTT seems a promising intervention to enhance recovery of ambulation and shorten hospital length of stay of ICU patients, justifying a sufficiently powered multicenter RCT.

Trial registration number: Dutch Trial Register ID: NTR6943.