Background <p>Lower limb arthroplasty (LLA), including total hip and total knee arthroplasty (THA and TKA), ranks among the most frequently performed elective orthopedic procedures worldwide. Patients on surgical waiting lists commonly present with reduced muscle strength, impaired mobility, and diminished cardiorespiratory fitness, all associated with delayed postoperative recovery. Prehabilitation aims to optimize preoperative functional capacity; however, adherence to center-based approaches remains suboptimal. Telerehabilitation offers a viable alternative, yet evidence on tele-prehabilitation for LLA candidates and comparisons between remote modalities remain scarce. This randomized clinical trial evaluated three tele-prehabilitation strategies on preoperative functional outcomes in patients awaiting LLA.</p> Methods <p>Sixty patients scheduled for elective TKA or THA were randomly allocated 1:1:1 to one of three four-week programmes: neuromuscular electrical stimulation (NMES), physiotherapist-supervised online exercise (SV), or unsupervised brochure-guided home exercise (BR), each comprising three 30-min sessions per week. No usual-care or non-intervention control group was included, as all three study arms received an active tele-prehabilitation intervention. Assessments were conducted at baseline (T0) and post-prehabilitation (T1) remotely via videoconference, and in person on postoperative day 4 (T2) and day 10 (T3). The primary outcomes were the 30-Second Chair Stand Test (30-CST), the Timed Up and Go test (TUG), and the Oxford Hip/Knee Score (OHS/OKS), assessed preoperatively at T0 and post-prehabilitation at T1. The secondary outcomes were the Six-Minute Walk Test (6MWT) and length of hospital stay (LOS), assessed postoperatively at day 4 (T2) and day 10 (T3). The a priori sample size calculation was based on the 6MWT as a clinically relevant and responsive indicator of early postoperative functional recovery following arthroplasty; the rationale for this choice and its implications for interpreting preoperative functional endpoints are discussed in the Limitations section.</p> Results <p>All three groups demonstrated significant within-group improvements across most functional outcomes (<i>p</i> &lt; 0.001). NMES achieved significantly greater reductions in TUG compared with both SV and BR, and superior gains in 6MWT and Oxford score relative to SV. No significant differences were observed between NMES and BR for 30CST, 6MWT, or Oxford score. Notably, BR demonstrated significantly greater improvement in 6MWT than SV, despite the absence of real-time supervision.</p> Conclusions <p>Tele-prehabilitation is feasible, well tolerated, and associated with meaningful functional improvements across all modalities. However, as all three groups received an active intervention, these findings reflect relative comparisons between remote modalities rather than efficacy versus standard care or no intervention. NMES demonstrated a more favorable comparative profile for selected mobility-related outcomes, particularly TUG, whereas no significant between-group differences were found for the 30-s chair stand test, particularly for mobility-related outcomes, while brochure-guided exercise proved largely equivalent to NMES on most endpoints. These findings support remote NMES and structured self-directed exercise as accessible, scalable alternatives to supervised prehabilitation for patients awaiting LLA.</p> Trial Registration <p>ClinicalTrials.gov Identifier: NCT06363643; Registered 12 April 2024. <a href="https://clinicaltrials.gov/study/NCT06363643">https://clinicaltrials.gov/study/NCT06363643</a></p>