Challenges with strengthening exercises for people with knee osteoarthritis and comorbid obesity: a qualitative study with patients and physiotherapists.

OBJECTIVE Explore challenges associated with implementing a home-based strengthening exercise program for people with knee osteoarthritis and comorbid obesity. METHODS Qualitative study embedded within a randomised controlled trial comparing two home-based strengthening programs (weight bearing functional exercise versus non-weight bearing quadriceps strengthening exercise) for people with knee osteoarthritis and comorbid obesity. Patients in both exercise programs attended five consultations with a physiotherapist and undertook a home-based exercise program for 12 weeks. Semi-structured individual telephone interviews were conducted with 22 patients after trial completion, and all seven physiotherapists who delivered trial interventions. Interviews were recorded, transcribed verbatim, and thematically analysed using an inductive approach. RESULTS Three themes arose: i) psychological challenges (false assumptions about exercise; fear of pain; disliking exercise; mental effort of weight bearing functional program; underestimating capability) ii) physical challenges (complexity of weight bearing functional program; cuff weights and straight leg raise problematic in non-weight bearing quadriceps program; other health conditions), and; iii) overcoming challenges (incentives to exercise; accountability; education and reassurance; tailoring the exercise program). CONCLUSION Patients and physiotherapists experienced numerous psychological and physical challenges to exercise, including a fear of pain, having false assumptions about exercise, difficulties with exercise performance, application of cuff weights, and adverse impacts of other health conditions.