The aim is to evaluate the test-retest reliability of the primary care-adapted Ekblom-Bak submaximal ergometer bicycle test in patients with hip- and/or knee osteoarthritis (OA).

Forty patients with hip- and/or knee OA eligible for the Swedish national OA treatment program in primary care are to be recruited. After screening for contraindications, participants will perform the aEB-test twice within 1-2 weeks.

The investigators hypothezise that the test will demonstrate acceptable test-retest reliability in patients with hip- and/or knee OA.

To establish reliability is essential for future studies using this test in this population and may support its integration into routine clinical assessment.

Inclusion Criteria:

• Currently listed on the waiting list for an osteoarthritis rehabilitation program due to clinically diagnosed hip and/or knee osteoarthritis.

Exclusion Criteria:

• Another primary cause of symptoms or disability, such as inflammatory joint disease or fracture.
• Another condition currently causing more symptoms than osteoarthritis, for example fibromyalgia.
• Insufficient understanding of written and spoken Swedish.
• Medication that affects heart rate.
• Contraindications for a submaximal ergometer bicycle test according to the screening protocol, such as heart disease.

Male or female