A case series evaluation of standardized exercise dosage using a cycle ergometer on body weight and patient-reported outcome measures among overweight female patients with knee osteoarthritis.

[Purpose] This case series aimed to evaluate the effects of a standardized exercise dosage using a cycle ergometer on body weight and patient-reported outcome measures among overweight female patients with knee osteoarthritis. [Participants and Methods] We conducted a two-phase study. Exercise dosage was standardized using kilocalories per kilogram of body weight per week. Study 1 verified the feasibility and safety of progressive dosage in a single participant, while Study 2 used an ABCB-type single-case design involving three participants. The participants performed a cycle ergometer exercise with standard physical therapy. Body weight was the primary outcome, and the Japan Knee Osteoarthritis Measure was the secondary outcome. [Results] In Study 1, the participant safely achieved an energy expenditure of up to 10 kilocalories per kilogram of body weight per week; however, symptoms resembling knee buckling occurred at an expenditure of 11 kilocalories per kilogram of body weight per week. In Study 2, no adverse events were observed. One participant significantly reduced body weight during Phase B2, and all participants exhibited an improvement in Japan Knee Osteoarthritis Measure scores. [Conclusion] Standardized exercise dosage based on kilocalories per kilogram of body weight per week provides a safe and effective method for overweight female patients with knee osteoarthritis.