A Catalog of "Knee Friendly" Aerobic Exercises Developed for Patients With Knee Osteoarthritis: An International Patient Survey

OBJECTIVE: Aerobic exercise is recommended for the management of knee osteoarthritis (OA), but knee pain is often a barrier for participation. Some types of aerobic exercise may be less painful to undertake than others, though little is known about which are the most "knee friendly," that is, unlikely to exacerbate knee pain to an unacceptable level. This study aimed to identify aerobic exercise activities that (1) are knee friendly and (2) meet requirements for targeting cardiovascular health.

METHODS: We conducted a three-phase international survey. In phase 1, persons living with knee OA provided descriptions of knee friendly exercise types, defined as activities that would cause shortness of breath and difficulty talking without worsening symptoms to an unacceptable level (cause severe symptoms and/or lasting more than 24 hours). In phase 2, exercise physiologists identified exercise activities meeting requirements for increasing aerobic fitness, which were grouped into broader aerobic exercise activities. In phase 3, participants nominated each aerobic exercise activity for "knee friendliness."

RESULTS: In phase 1, 487 respondents (Denmark: 259; the Netherlands: 144; Australia: 57; and North America: 15) provided a total of 1,590 exercise descriptions. In phase 2, 154 exercise activities were identified and grouped into a list of 30 broader aerobic exercise activities. In phase 3, 349 participants (Denmark: 195; the Netherlands: 114; Australia: 32; and North America: 8) nominated indoor biking and water exercise as most knee friendly (82% and 70%, respectively). Participants were predominantly women (60.7%), the mean ± SD age was 68.4 ± 8.81 years, the mean ± SD body mass index was 27.5 ± 5.8, the mean ± SD self-efficacy score was 7.3 ± 3.0 (0-10 scale), the mean ± SD symptom duration was 11.7 ± 9.05 years, and the mean ± SD current knee pain was 4.5 ± 2.2 (0-10 scale).

CONCLUSION: A catalog of 30 knee friendly aerobic exercise activities was generated for individuals living with knee OA. The catalog aims to empower individuals living with knee OA, offering suitable aerobic exercise options without exacerbating knee pain.