Objectives. We compared mindsets about physical activity among those with and without knee osteoarthritis and investigated if these mindsets relate to physical activity level and symptom management.
Methods. Participants with (n=150) and without (n=152) knee osteoarthritis completed an online survey at study enrollment (T1). Participants with knee osteoarthritis repeated the survey three weeks later (T2; n=62). The mindset questionnaire, scored from 1-4, assessed the extent to which individuals associate the process of exercising with less appeal-focused qualities (e.g., boring, painful, isolating, and depriving) vs. appeal-focused (e.g., fun, pleasurable, social, and indulgent) versus. Using linear regression, we examined the relationship between mindset and having knee osteoarthritis, and, in the subgroup of participants with knee osteoarthritis, the relationship between mindset at T1 and physical activity (via the Physical Activity Scale for the Elderly) at T2. We also compared mindsets between those who use medication for management and those who use exercise.
Results. A less appeal-focused mindset regarding physical activity was marginally associated with having knee osteoarthritis (β=-0.125, P=0.096). Within the knee osteoarthritis group, a more appeal-focused mindset predicted higher future physical activity (β=20.68, P=0.039), controlling for current physical activity, demographics, and health. Individuals that used exercise with or without pain medication or injections had more appeal-focused process mindsets than those who used medication or injections without exercise (P<0.001). Further, the process mindset inventory demonstrated strong internal consistency (α=0.92 at T1 for n=150 and α=0.92 at T2 for n=62) and test-retest reliability (ICC>0.841, P<0.001) within the knee osteoarthritis population.
Conclusion. In individuals with knee osteoarthritis, mindsets predict future physical activity levels and relate to an individual's management strategy. Mindsets are a reliable and malleable construct and may be a valuable target for increasing physical activity and improving adherence to rehabilitation strategies involving exercise among individuals with knee osteoarthritis.
The Association Between Daily Physical Activity and Pain Among Patients with Knee Osteoarthritis: The Moderating Role of Pain Catastrophizing
