Background:Despite the routine use of physical therapy in the immediate and early postoperative phase for patients who undergo total knee replacement (TKR), there is a paucity of research into the optimal exercise protocols in both the acute inpatient setting and early period after discharge. Pedaling has often been recommended by clinicians after TKR for rehabilitation, but to our knowledge, there has been no investigation into its utility in the acute postoperative setting. Therefore, we performed a randomized controlled trial evaluating the efficacy of pedaling in the acute postoperative period.Methods:Sixty TKR patients were randomized to receive postoperative physical therapy involving either a 3-exercise pedaling (pedaling-based) or 10-exercise, non-pedaling (multi-exercise) protocol. Outcomes were assessed at 2 days, 2 weeks, and 4 months, and included physical tests of function, patient-reported outcomes, and other perioperative measures.Results:With respect to the primary outcome, the 6-minute walk test (6MWT), the measured distance was significantly greater in the pedaling-based group than in the multi-exercise group at 2 days postoperatively (mean difference, 66 m; p = 0.001). Results of other functional tests, the 10-m walk test (10MWT) and the Timed Up & Go (TUG) test, were both significantly superior for the 3-exercise pedaling group at 2 days (p = 0.016 for 10MWT, and p = 0.020 for TUG), as was the patient-reported Oxford Knee Score (p = 0.034). The latter continued to be superior at 2 weeks (p = 0.007), as was the EQ-5D score (p = 0.037). The visual analogue scale (VAS) component of the EQ-5D was significantly better for the pedaling group at all time points assessed. Length of stay was also significantly shorter, by a half-day, for the pedaling-based group (median of 2.5 days compared with 3.0 days for the multi-exercise group; p = 0.024). The multi-exercise protocol was not superior for any outcome measure at any time point.Conclusions:A pedaling-based protocol in the immediate postoperative period after TKR was superior to a standard multi-exercise protocol in both functional and patient-reported outcomes, with these benefits decreasing over time.Level of Evidence:Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.