Which symptom is commonly associated with rheumatoid arthritis?

Morning stiffness lasting more than one hour is a hallmark symptom of rheumatoid arthritis (RA). Patients with this condition often experience prolonged stiffness in their joints after periods of inactivity, which can notably impact their daily functioning. This stiffness is typically reported as lasting more than one hour and can improve with movement throughout the day.

In rheumatoid arthritis, this symptom arises due to inflammation in the synovial membranes surrounding the joints, leading to a feeling of rigidity when a person begins to move after waking up or after having been inactive. The presence of this symptom, especially when it occurs on a regular basis, is an important clinical feature that physicians use in the diagnosis of rheumatoid arthritis, distinguishing it from other musculoskeletal conditions.

Other options reflect different conditions or symptoms that are not typical of rheumatoid arthritis. Joint hypermobility is often associated with conditions like Ehlers-Danlos syndrome rather than RA. Muscle hypertrophy is more aligned with muscular training or conditions that involve increasing muscle mass and is not a symptom of RA. Immediate swelling after exercise would more likely indicate an acute injury or different inflammatory condition, rather than the chronic joint involvement typically seen in rheumatoid arthritis. Thus, the specificity of morning stiffness for rheumatoid arthritis reinforces why this symptom is the correct answer.