FREquency of strength home exercises for knee osteoarthritis pain: Protocol for the FRESH non-inferiority randomised controlled trial.

OBJECTIVE

To determine if a strength exercise program prescribed once a week is non-inferior to the same program prescribed three times a week, as measured by change in average walking pain at 3 months post-randomisation, in people with knee osteoarthritis (OA).

DESIGN

A parallel two-arm non-inferiority randomised controlled trial, involving 178 people aged ≥45 years, with chronic knee pain consistent with OA. This protocol is reported in accordance with SPIRIT 2025 guidelines. Following baseline assessment, participants are randomised (1:1 allocation ratio) to receive the same home strength exercise program (3 sets of 12 repetitions of 5 lower limb exercises for approximately 3 months) prescribed either i) once weekly or ii) three times weekly. Participants are then randomly assigned to a physiotherapist, who prescribes the exercise program via videoconferencing at the allocated frequency. The primary outcome is the change in knee pain intensity during walking, measured on a numerical rating scale (0-10) at 3 months. Secondary outcomes include the Western Ontario and McMaster Universities Arthritis Index pain and function subscales, quality-of-life, arthritis and exercise self-efficacy, global rating of change, patient-specific functional scale, acceptance of symptoms, muscle strength/power, and willingness to undergo joint replacement.

ETHICS AND DISSEMINATION: Approved by the University of Melbourne Human Research Ethics Committee (#2025-33625-70884-3). Dissemination will occur via infographics, lay summaries, conference abstracts, presentations, and journal publications.

CLINICAL TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry #ACTRN12625001084471. Prospectively registered on 3/10/2025.

CONCLUSIONS

Findings will determine whether a less frequently prescribed exercise program is non-inferior to a more frequent exercise program for pain in knee OA.